using adams/driveline - md adams 2010

Welcome to Adams/Driveline

Adams/DrivelineAbout Adams/Driveline

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About Adams/DrivelineYou can use Adams/Driveline, part of the MD Adams 2010® suite of software, stand alone or as a plugin for Adams/Car. You use Adams/Driveline to model drivelines: to create virtual prototypes of driveline subsystems and analyze the virtual prototypes much like you would analyze the physical prototypes.

Using Adams/Driveline, you can quickly create assemblies of suspensions and full vehicles, including driveline components, and then analyze them to understand their performance and behavior. Learn about Building Models.

You create assemblies by defining vehicle subsystems, such as front and rear suspensions, steering gears, anti-roll bars, and bodies. You base these subsystems on their corresponding Adams/Driveline templates. For example, Adams/Driveline includes templates for engine, gearbox, prop shafts, and differentials.

If you have expert-user access, you can also base your subsystems on custom templates that you create using the Adams/Driveline Template Builder (see Interface Modes).

When you analyze an assembly, Adams/Driveline applies the Analysis inputs that you specify. For example, for a full-vehicle analysis you can specify inputs to:

• Apply a specific torque to your driveline model (impulse, step, ramp, loadcase, and so on).

• Define a different friction coefficient for different wheels in your model.

• Define a slope of your road to study the performance of your driveline model.

Based on the analysis results, you can quickly alter the driveline geometry and analyze the driveline again to evaluate the effects of the alterations. Once you complete the analysis of your model, you can share your work with others. You can also print plots of the vehicle dynamic responses. In addition, you can access other users’ models without overwriting their data.

Benefits of Adams/DrivelineAdams/Driveline enables you to work faster and smarter, letting you have more time to study and understand how design changes affect vehicle performance.

Using Adams/Driveline you can:

• Explore the performance of your design and refine your design before building and testing a physical prototype.

• Analyze design changes much faster and at a lower cost than physical prototype testing would require. For example, you can change springs with a few mouse clicks instead of waiting for a mechanic to install new ones in your physical prototype before re-evaluating your design.

• Vary the kinds of analyses faster and more easily than if you had to modify instrumentation, test fixtures, and test procedures.

• Work in a more secure environment without the fear of losing data from instrument failure or losing testing time because of poor weather conditions.

• Run analyses and what-if scenarios without the dangers associated with physical testing.

Backlash Components

This component represents a backlash gap between two parts. In Adams/Driveline you can work with two types of backlash components: rotational and translational backlash.

Learn about backlash:

• Creating or Modifying Backlash

• About Rotational Backlash

• About Translational Backlash

Creating or Modifying Backlash

To create or modify backlash:

1. From the Driveline Components menu, point to Translational/Rotational Backlash, and then select New/Modify.

2. Press F1 and then follow the instructions in the dialog box help for Backlash.

3. Select OK.

About Rotational BacklashA rotational backlash describes a rotational connection between two parts that are connected using a revolute joint and a rotational single-component force that describes the backlash. In addition, Adams/Driveline creates a fixed joint to allow the possibility of deactivating the backlash.

In the Standard Interface (see Interface Modes), you can use the Driveline Activity Wizard to manage the activity of each backlash element.

Note: Adams/Driveline automatically creates some kinematic joints in this component.

Adams/DrivelineBacklash Components

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The backlash law is defined with a combination of ATAN functions to guarantee smoothness and derivative continuity

.

where:

• T = Resulting torque

• sharp = Sharpness factor of the backlash

• = Relative angles of the two markers defining the backlash force

• lash = Backlash (in radians)

• stiff = Stiffness of the gear-to-gear contact

• damp = Damping of the gear-to-gear contact

The sharpness factor lets you control how sharp the transition is between the lash region with zero forces and the stiff region.

In this model, the expression of the sharpness factor is as follows:

This means that the backlash needs some time to be fully developed with the steady-state value of Nx.

This device makes integration easier. Nx is the value you define in the Rotational Backlash Create/Modify dialog box.

T 1–

sharp lash2

-----------– atan

pi--------------------------------------------------------------- 0.5+

stiff lash2

-----------– damp

t

------+ +=

sharp lash2

-----------+ atan

pi--------------------------------------------------------------- 0.5–

stiff lash2

-----------+ damp

t

------+

3Backlash Components

Sharpness Factor Development Time


4

Backlash Force as Function of Sharpness Factor (N=10, 500, 1000)

In the Standard Interface, you can vary values for the following:

• Backlash

• Stiffness

• Damping

• Sharpness factor


Request Definition

Result name: backlash_states

Subsystem Parameters

• Backlash flag

• Backlash

• Stiffness

• Damping


About Translational BacklashA translational backlash describes a translational connection between two parts that are connected using a translational joint and a translational single-component force that describes the backlash. In addition, Adams/Driveline creates a fixed joint to allow the possibility of deactivating the backlash.

In the Standard Interface (see Interface Modes), you can manage the activity of each backlash element using the Activity Wizard.

The backlash law is defined with a combination of ATAN functions to guarantee smoothness and derivatives continuity.

Component: Component

name:Component

units: Definition:

F2 displacement angle The angle between the two parts connected with the backlash element.

F3 angular_velocity angular velocity The relative rotational velocity between the two parts connected by the backlash element.

F4 force force Force exerted by the backlash element.



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where:

• F = Resulting force

• sharp = Sharpness factor of the backlash

• x = Relative displacement of the two markers defining the backlash force

• lash = Backlash in mm

• stiff = Stiffness of gear-to-gear contact

• damp = Damping of the gear-to-gear contact

The sharpness factor lets you control how sharp the transition is between the lash region with zero forces and the stiff region.

In this model, the expression of the sharpness factor has been defined as follows:

This means that the backlash needs some time to be fully developed with the steady-state value of Nx.

This device makes integration easier. Nx is the value you select in the appropriate dialog box.

F 1–

sharp xlash

2-----------–

atan

pi-------------------------------------------------------------- 0.5+

stiff xlash

2-----------–

dampxt

-----+ +=

sharp xlash

2-----------+

atan

pi-------------------------------------------------------------- 0.5–

stiff xlash

2-----------+

dampxt

-----+


Sharpness Factor Development Time


8

Backlash Force as Function of Sharpness Factor (N=10, 500, 1000)


• Backlash

• Stiffness

• Damping



Request Definition

Result name: backlash_states


• Backlash flag

• Backlash

• Stiffness

• Damping


Component: Componen

t name:Component

units: Definition:

F2 displacement length The angle between the two parts connected with the backlash element.

F3 velocity velocity The relative rotational velocity between the two parts connected by the backlash element.

F4 force force Force exerted by the backlash element.

Adams/DrivelineBearings

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Bearings

A bearing component describes a force-based connection between two parts. Adams/Driveline models a bearing with a six-component force and allows the two parts to rotate around the z-axis. Adams/Driveline also models all contact forces and drag. You can specify both radial and axial backlash for the bearing.

Learn about bearings:

• Creating or Modifying Bearings

• About Bearings

• Modeling Bearings

• Example Bearing Property File

Creating or Modifying BearingsTo create or modify a bearing:

• From the Driveline Components menu, point to Bearing, and then select New/Modify.

• Press F1 and then follow the instructions in the dialog box help for Bearing.

• Select OK.

About BearingsIn Adams/Driveline you can create two types of bearings:

• Axial

• Tapered

The driveline bearing formulation is based on values obtained from the Timken Company manual (for free online resources register at http://www.timken.com/timken_ols/bearings/). The running torque equations are for bearings whose torque has stabilized after a period of running under operating conditions, so called a "running" bearing. The equations apply to bearings lubricated with circulating oil or oil level systems. You can use the equations to model all single-row bearing loading conditions.

The component consists of the following objects:

http://www.timken.com/timken_ols/bearings/

11Bearings

• A general force component featuring the actions and reactions between the inner and outer ring of the bearing.

• A request to output force and torque values.

• Two revolution geometries to visualize the rings. The component creates these geometries on the parts to be connected by the bearing (that is, shaft and housing).

Adams/Driveline calculates the forces and torques between the rings using a user-defined general force, which acts properly depending on the bearing type.

Displacement Request (disp_request)

Velocity Request (velo_request)


name:Component

units: Definition:

F2 dx length The displacement between the i marker and the reference marker in the x direction.

F3 dy length The displacement between the i marker and the reference marker in the y direction.

F4 dz length The displacement between the i marker and the reference marker in the z direction.

F6 ax angle The angular displacement between the i marker and the reference marker around the x-axis.

F7 ay angle The angular displacement between the i marker and the reference marker around the y-axis.

F8 az angle The angular displacement between the i marker and the reference marker around the z-axis.


name:Component

units: Definition:

F2 vx velocity The velocity between the i marker and the reference marker in the x direction.

F3 vy velocity The velocity between the i marker and the reference marker in the y direction.

F4 vz velocity The velocity between the i marker and the reference marker in the z direction.

F6 wx angular velocity The angular velocity between the i marker and the reference marker around the x-axis.


12

Force Request (force_request)

Adams/Driveline calculates the force and torque for the bearing using backlash expressions. The force or torque is almost zero until the relative translational or angular displacement is lower than the specified lash, then the force or torque follows an elastic law.

For tapered roller bearings, the thrust force acts only along one direction (z-positive), being zero along the other.

The reaction forces in the three translational directions are defined with a linear stiffness + backlash. The two cardanic reaction torques are calculated based on the translational forces and the geometric properties (bearing diameter). Learn about the rotational backlash formulation.

To calculate the running torque of the bearing, depending on several factors (bearing geometry, applied loads, load zone, speed of rotation, and so on) the following expressions have been used:

F7 wy angular velocity The angular velocity between the i marker and the reference marker around the y-axis.

F8 wz angular velocity The angular velocity between the i marker and the reference marker around the z-axis.


name:Component

units: Definition:

F2 fx force The force between the i marker and the reference marker in the x direction.

F3 fy force The force between the i marker and the reference marker in the y direction.

F4 fz force The force between the i marker and the reference marker in the z direction.

F6 tx torque The torque between the i marker and the reference marker around the x-axis.

F7 ty torque The torque between the i marker and the reference marker around the y-axis.

F8 tz torque The torque between the i marker and the reference marker around the z-axis.


name:Component

units: Definition:

13Bearings

Radial load or combined radial thrust load:

Pure thrust load:

where:

• T = Running torque

• k1 = Constant being 2.56e-5 for T in N*m, 3.54e-5 for T in lbf*in

• G1 = Bearing geometry factor

• S = Running speed (rpm)

• Mu = Lubricant viscosity (Cp)

• K = Bearing K-factor. The K-factor is the ratio of basic dynamic radial load rating to basic dynamic thrust load rating of a single row bearing.

• f1 = Combined load factor. The combined load factor can be read from Timken tables as a function of (K*Fa)/(Fr).

• Fr = Radial load

• Fa = Thrust road

Request Definition


name:Component

units: Definition:

F2 angle angle The angle between the two parts (gear and shaft).

F3 angular_velocity angular velocity The relative velocity between the two parts connected with the synchronizing force component.

F4 torque torque Rotational force exerted by the synchronizer component.


14

Modeling BearingsIn Adams/Car and Adams/Driveline you can model bearings in different ways, according to the effects you want to observe in your models.

If, for example, you want to model a shaft with two bearings, the simplest solution is to connect the shaft to the case with a revolute joint. The revolute joint is an ideal constraint that removes five degrees of freedom. With this solution, compliance and drag effects are ignored. In addition, reaction forces on the revolute joint are not comparable with the reaction forces you experience in a physical model.

A second solution is provided with a combination of kinematic joints: an inline primitive joint and a spherical joint. The inline acts as a pure radial bearing (ideal) and the spherical joint as a combined radial and axial bearing. This solution still does not take into account compliance and drag effects but provides meaningful reaction forces.

When you want to model the connection between shaft and case, taking into account the compliance effects, you can use the standard Adams/Car bushing element. You can define the radial and axial stiffnesses using force versus displacement characteristics, and approximate the drag effects with a constant rotational damping.

The Adams/Driveline bearing component allows you to specify, in the three translational directions, a linear stiffness with backlash effects. It also allows you to specify the same for the torques in the x and y direction, while the torque along the z (spin) direction is computed based on values obtained from the Timken Company manual (for free online resources register at http://www.timken.com/timken_ols/bearings/). You can use the current implementation to model all single-row bearing loading conditions, except for the pure thrust load (that means radial or combined radial and thrust load bearing).

Example Bearing Property File

$--------------------------------------------------MDI_HEADER[MDI_HEADER]FILE_TYPE = 'bea'FILE_VERSION = 4.0FILE_FORMAT = 'ASCII'$--------------------------------------------------UNITS[UNITS]LENGTH = 'mm'ANGLE = 'degrees'FORCE = 'newton'MASS = 'kg'TIME = 'second'$----------------------------------------------BEARING_PARAMETERS[BEARING_PARAMETERS]G1 = 1000 MU = 10K_FACTOR = 1$--------------------------------------------------BEARING_SPLINE[BEARING_SPLINE]

http://www.timken.com/timken_ols/bearings

15Bearings

{ x y}-100.0 6.0E-02-50.0 6.0E-020.0 6.0E-0250.0 6.0E-02100.0 6.0E-02

Adams/DrivelineChains

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Chains

This component describes a simplified chain model in its global behavior. This component does not model chain parts. It does, however, model the global behavior of the chain, which is a torsional load and a longitudinal force (tension).

Learn about chains:

• Creating or Modifying Chains

• About Chains

Creating or Modifying ChainsTo create or modify a chain:

1. From the Driveline Components menu, point to Chain, and then select New/Modify.

2. Press F1 and then follow the instructions in the dialog box help for Chain.

3. Select OK.

About ChainsA chain describes a force-based connection between two sprockets. In Adams/Driveline you create a simple chain model in which no chain links are modeled. Adams/Driveline models torsional and translational loads in the chain with a rotational spring damper and a single-component force.

If you want to take into account the backlash effect, you can connect each sprocket to the respective shaft with a rotational backlash component.

If you want to have a transmission ratio different from 1:1, you can connect the output sprocket to another part with a kinematic gear component.

Adams/Driveline creates the following forces between the input and the output sprocket:

17Chains

• A rotational spring damper (acting between CM marker of the input sprocket and the CM marker of the output sprocket).

• A translational single-component force (acting between driving sprocket and driven sprocket).

The translational force expression is:

-TM(Input sprocket marker, output sprocket marker) / Input Sprocket Radius

If you decide to use the gear geometry (revolution) for sprockets, the radius will be deduced from that component. Otherwise, you will have to enter the value in the create/modify dialog box.

In the Standard Interface (see Interface Modes), you can vary values for the following:

• Rotational stiffness

• Rotational damping

• Sprocket radius (in case gear geometry has not been used)


• Stiffness

• Damping

Note: The reason why a rotational spring damper is used instead of a coupler is so that chain elastic characteristics can be taken into account.

Adams/DrivelineChurning-Drag Forces

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Churning-Drag ForcesThe churning-drag force component allows you to model the oil resistance acting on gears when they rotate in oil. A churning drag describes a force-based component that models the oil resistance that forms between gears and the gearbox case as soon as gears have a relative angular velocity with respect to the gearbox case.

Learn about churning-drag components:

• Creating or Modifying Churning-Drag Forces

• About Churning-Drag Forces

Creating or Modifying Churning-Drag ForcesTo create or modify churning-drag forces:

1. From the Driveline Components menu, point to Churning Drag, and then select New/Modify.

2. Press F1 and then follow the instructions in the dialog box help for Churning-Drag Force.

3. Select OK.

About Churning-Drag ForcesAdams/Driveline calculates the resistance force using a rotational single-component force and its expression is as follows:

SIGN(K * Viscosity * B * Diam2 * ABS(wz)1.5, -wz)

where:

• K = Constant (default 3.0E-12)

• B = Gear breadth

• Diam = Diameter

• wz = Angular velocity


• Constant

• Breadth

• Viscosity

• Diameter

19Churning-Drag Forces


name:Component

units: Definition:

F2 angular displacement

angle The angle between the two parts.

F3 angular_velocity angular velocity The relative velocity between the two parts connected with the churning drag component.

F4 torque torque Rotational force exerted by the churning drag component.

Adams/DrivelineClutch Connectors

20

Clutch Connectors

This component allows you to use the clutch connector in the driveline model. A property file stored in the database determines the clutch connector characteristics. The component consists of a torque acting between the two selected parts with the location and the orientation determined by a specified construction frame.

Learn about clutch connectors:

• Creating or Modifying Clutch Connectors

• About Clutch Connectors

Creating or Modifying Clutch ConnectorsTo create or modify clutch connectors:

1. From the Driveline Components menu, point to Clutch Connector, and then select New/Modify.

2. Press F1 and then follow the instructions in the dialog box help for Clutch Connector.

3. Select OK.

About Clutch ConnectorsThe component contains the following elements:

• Single component force

• IC motion (used to set the initial velocity)

• Array storing the data read in the property file before submitting the Analysis

• Request

The following defines the clutch connector force:

Torque = STEP(WZ(I_MAR, J_MAR, J_MAR), 0,0, positive_velocity_threshold, max_positive_transmitted_torque) + STEP(WZ(I_MAR, J_MAR, J_MAR), 0,0, Negative_velocity_threshold, max_negative_transmitted_torque) - WZ(I_MAR, J_MAR, J_MAR)*30/PI*drag_coefficient)

21Clutch Connectors

In steady-state conditions, equal rotational velocity of the two bodies produces a 0.0 torque.

In Template Builder (see Interface Modes), when you create a clutch connector, you can specify:

• I part

• J part

• Coordinate reference (construction frame)

• Property file

In Standard Interface you can vary the property file.

The request outputs the following values:

• The angle between the two parts along the reference frame z-axis

• The angular velocity between the two parts along the reference frame z-axis

• The torque transmitted between the two parts

Request Definition

Result name: torque_cvtr_variables


Property file (<db_name>/clutch_connectors.tbl)


name:Component

units: Definition:

F2 angle angle The angle between the two parts along the reference frame z-axis.

F3 angular velocity angular velocity The angular velocity between the two parts along the reference frame z-axis.

F4 torque torque The torque acting between the two parts.

Adams/DrivelineClutch Forces

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Clutch Forces

This component represents contact forces in a clutch component. It models normal contact forces, as well as friction forces.

Learn about clutch forces:

• Creating or Modifying Clutch Forces

• About Clutch Forces

• Example Clutch-Force Property File

Creating or Modifying Clutch ForcesTo create or modify clutch forces:

1. From the Driveline Components menu, point to Clutch Forces, and then select New/Modify.

2. Press F1 and then follow the instructions in the dialog box help for Clutch Force.

3. Select OK.

About Clutch ForcesContact forces are modeled using a property file which stores the cushion characteristic. The behavior is very similar to a bumpstop element: no force in one direction, and force in the other one when the distance between two parts (for example, flywheel and pressure plate) is smaller than a specified clearance. The property file is stored in a designated directory of the database named <db_name>/clutch_forces.tbl/*.clu.

Adams/Driveline models friction forces by multiplying contact forces with a friction coefficient and an effective radius that you specify.

23Clutch Forces

The friction coefficient is defined as a function of the relative angular velocity between the two parts. You can also take into account both the static and dynamic friction coefficient.

The following figure shows a typical friction versus relative slip.

Using the create/modify dialog box, you can observe how the friction function changes by changing parameters such as the static and dynamic friction coefficient.

In Standard Interface, you can vary values for the following:

• Property file

• Impact length

• Static friction coefficient

• Dynamic friction coefficient

• Static velocity

• Dynamic velocity

• Effective friction radius

Example Clutch-Force Property File

$--------------------------------------------------MDI_HEADER[MDI_HEADER]FILE_TYPE = 'clu'FILE_VERSION = 4.0FILE_FORMAT = 'ASCII'$--------------------------------------------------UNITS[UNITS]

Adams/DrivelineClutch Forces

24

LENGTH = 'mm'ANGLE = 'degrees'FORCE = 'newton'MASS = 'kg'TIME = 'second'$--------------------------------------------------DAMPING [DAMPING]DAMPING = 10$--------------------------------------------------CURVE [CLUTCH_FORCE]{ disp force}0.0 0.03.50 40000.05.50 90000.0 7.60 130500.0 12.10 180000.0 15.50 270000.0 17.56 297900.0 40.635 378000.0

25Complex Springs

Complex SpringsThis component represents a complex rotational spring with hysteresis. You can use it to model rotational springs in clutch friction disks, as well as any other connection in which a rotational spring damper with hysteresis is needed.

Learn about complex springs:

• Creating or Modifying Complex Springs

• About Complex Springs

• Calculation of Complex Spring Force

• Example Complex-Spring Property File

Creating or Modifying Complex SpringsTo create or modify complex springs:

1. From the Driveline Components menu, point to Complex (Torsional) Spring, and then select New/Modify.

2. Press F1 and then follow the instructions in the dialog box help for Complex (Torsional) Spring.

3. Select OK.

About Complex SpringsThis complex spring represents a torsional spring with hysteresis. You can use it to model rotational springs in clutch friction disks, as well as any other connection in which a rotational spring damper with hysteresis is needed.

The hysteresis effect is accomplished using two different splines (loading and unloading) stored in a specific property file (<db_name>/complex_springs.tbl/*.csp). Adams/Solver switches from one spline to the other according to the value of angular velocity between the I and J marker. The value of velocity at which the transition has to occur is also stored in the property file. Using two splines allows you to take into account different values of hysteresis for different values of angular displacement. See the following figure.

Adams/DrivelineComplex Springs

26

Torque versus Angular Displacement

In addition, the dependency of hysteresis from engine RPM is taken into account, since loading and unloading splines are three-dimensional splines. The first independent variable is the angular displacement and the second independent variable is engine RPM.

Before submitting an Analysis, you can switch the hysteresis effect on or off from the modify dialog box. If you set Hysteresis Activity to no, Adams/Driveline uses only the first spline (loading) to evaluate the force exerted by this component. In the Standard Interface (see Interface Modes), you can vary values for the following:

• Property file

• Hysteresis activity

Calculation of Complex Spring Force The complex spring force is calculated as follows:

FORCE = - load_step * load_scale_factor * load_spline - hysteresis_activity * step2 * unload_scale_factor * unload_spline - damping * WZ

where:

• load_step = step5(WZ,- TRANSITION_VELOCITY/2, 1-activity, TRANSITION_VELOCITY, 1)

• unload_step = step5(WZ,- TRANSITION_VELOCITY, 1, TRANSITION_VELOCITY/2, 0)

• load_spline = akispl(AZ,load_spline, 0)

• unload_spline = akispl(AZ,unload_spline, 0)

27Complex Springs

When hysteresis_activity is set to off (0), the spring acts as a nonlinear torsion spring with viscous damping, and only the first spline is used.

Note that you can also model torsion spring with hysteresis (and it's easier to define its parameters) using the torsion spring.

Example Complex-Spring Property File

$--------------------------------------------------MDI_HEADER[MDI_HEADER]FILE_TYPE = 'csp'FILE_VERSION = 4.0 FILE_FORMAT = 'ASCII'$--------------------------------------------------UNITS[UNITS]LENGTH = 'mm'ANGLE = 'degrees'FORCE = 'newton' MASS = 'kg'TIME = 'second'$-----------------------------------------------SPRING_PARAMETERS[SPRING_PARAMETERS]TRANSITION_VELOCITY = 1e-1 DAMPING = 50 $--------------------------------------------------LOADING_SPLINE [LOADING_SPLINE] (Z_DATA) {rpm} 0.0 1000.04000.0 (XY_DATA) { x y}-60 -400000 -400000 -400000-50 -300000 -300000 -300000-40 -220000 -220000 -220000 -30 -175000 -175000 -175000 -20 -115000 -115000 -115000-10 -50000 -50000 -500000 0 0 010 30000 30000 30000 20 50000 50000 5000030 100000 100000 10000040 160000 160000 160000 50 200000 200000 200000 60 400000 400000 400000

$--------------------------------------------------UNLOADING_SPLINE [UNLOADING_SPLINE] (Z_DATA){rpm} 0.0 1000.0

Adams/DrivelineComplex Springs

28

4000.0 (XY_DATA) { x y}-60 -400000 -400000 -400000-50 -200000 -200000 -200000-40 -150000 -150000 -150000 -30 -110000 -110000 -110000 -20 -70000 -70000 -70000-10 -25000 -25000 -25000 0 0 0 0 10 50000 50000 5000020 110000 110000 110000 30 180000 180000 18000040 220000 220000 220000 50 300000 300000 300000 60 400000 400000 400000

29Conceptual Wet Clutches

Conceptual Wet ClutchesA wet clutch is a torque that connects an I part and a J part.

Learn about wet clutches:

• Creating or Modifying Wet Clutches

• About Wet Clutches

Creating or Modifying Wet ClutchesTo create or modify wet clutches:

1. From the Driveline Components menu, point to Conceptual Wet Clutch, and then select New/Modify.

2. Press F1 and then follow the instructions in the dialog box help for Wet Clutch.

3. Select OK.

About Wet ClutchesThe torque expression is based on the inputs stored in the property file, such as number of surfaces, effective radius, pressure area, turning point pressure, and MU.

The torque converter element also includes a clutch part that is connected to the J part. The two parts are connected with a torsion spring (in the property file you also specify the Clutch Compliance Stiffness and Clutch Compliance Damping parameters).

Adams/Driveline uses the following formulas to evaluate the resulting torque:

Clutch Capacity=STEP(varval(clutch_pressure),0,0,0.1,1)* number_of_surface * effective_radius * clutch_mu * pressure_area * VARVAL(clutch_pressure) Torque=clutch_capacity * clutch_switch

In the Standard Interface (see Interface Modes), you can vary the property file.

Request Definition

Result name: request1


name:Component

units: Definition:

F2 angle angle The angle between the I and J part.

F3 Angular_velocity angular velocity The angular velocity of the I part with respect to the J part.

F6 Clutch_pressure pressure The input pressure of the clutch.

Adams/DrivelineConceptual Wet Clutches

30


Property file (<db_name>/clutch_forces.tbl)

F7 capacity torque The capacity that the clutch is able to develop.

F7 capacity torque The torque the clutch applies between the I and J parts.


name:Component

units: Definition:

31Gear Forces

Gear Forces

This component represents a gear couple. You can use it to model Spur Gears and Bevel Gears.

Learn about gear forces:

• Creating or Modifying Gear Forces

• About Gear Forces

Creating or Modifying Gear Forces

To create or modify gear forces:

1. From the Driveline Components menu, point to Gear Force, and then select New/Modify.

2. Press F1 and then follow the instructions in the dialog box help for Gear Force.

3. Select OK.

About Gear ForcesThe component consists of the following objects:

• Two general forces, featuring the actions exchanged between the gear meshes.

• A request to output force and torque values.

Adams/Driveline calculates the forces and torques between the gears using a user-defined general force, whose action depends on the gear type.

To get reaction forces in the right direction, you must identify the orientation of the construction frames used to define the gear forces. The following figure shows how construction frames must be oriented. Notice that:

Adams/DrivelineGear Forces

32

• The z-axis must be oriented along the rotation axis

• The x-axis has to point to the contact point

• The y-axis is located based on the x- and z-axes

Construction Frame Orientations

You can specify the parameters as shown next:

Adams/Driveline calculates the transmitted torque for the gears using a backlash expression. (Torque is almost zero until the relative angular displacement, scaled by gear ratio, is lower than the specified lash, then the torque follows an elastic law.) Learn about rotational backlash.

The other torque and force components (radial and thrust) are derived from the transmitted torque expression and from the gear type.

Parameter: Description:

Gear type Spur, bevel

Gear diameters Pitch diameter (depending on geometries)

Backlash Allowed angular backlash

Stiffness Contact rotational stiffness

Damping Contact rotational damping

Sharpness factor See Rotational Backlash

Pressure angle a --

Average gear radius for bevel gear Taken from geometry

33Gear Forces

Spur Gears

From the transmitted torque, Adams/Driveline calculates the radial forces as follows:

where:

• Tz = Transmitted torque

• Rp = Gear primitive radius

• = Pressure angle

Bevel Gears

From the transmitted torque, Adams/Driveline evaluates the radial and thrust forces expressions as follows:

where:

• Fx = Radial load

• Fz = Thrust load

• = Gear ratio

Adams/DrivelineGear Pairs

34

Gear Pairs

This component represents a connection between two gears on two different shafts, according to a gear ratio and a specified rotational backlash. To create a gear pair, input and output shafts, and input and output gears must exist. A coupler element constrains the rotation of the output gear to the input gear.

Learn about gear pairs:

• Creating or Modifying Gear Pairs

• About Gear Pairs

Creating or Modifying Gear Pairs

To create or modify gear pairs:

1. From the Driveline Components menu, point to Gear Pair, and then select New/Modify.

2. Press F1 and then follow the instructions in the dialog box help for Gear Pair.

3. Select OK.

About Gear PairsYou can use gear pairs to model the connection between spur gears of a constant mesh gearbox model. In the constant mesh gearbox all gears are positively meshed to each other. They are mounted on bearings and, when selected, are coupled to proper shafts by means of various types of devices. The gear pair component consists of:

• Ideal bearing between input shaft and gear (modeled as revolute joint).

• Ideal bearing between output shaft and gear (modeled as revolute joint).

• Two perpendicular joints that constrain, on demand, the residual rotational degree of freedom of the input and output gears.

• Coupler between the two revolute joints representing the positive connection between gears.

• An additional dummy part (mesh carrier). .


35Gear Pairs

The dummy part is required to allow proper behavior of the mechanism. Adams/Driveline creates the part representing the mesh carrier within the UDE instance. It is used to effectively define the connection of the input gear to the output gear via coupler element. Without the mesh carrier part, a rigidly connected input gear would not produce any rotation of the output gear with respect to the output shaft.

You can select the initial configuration of the synchronizing mechanism by choosing one of the following options:

• Input gear connected to input shaft (input gear perpendicular JPRIM is active)

• Output gear connected to output shaft (output gear perpendicular JPRIM is active)


• Reduction ratio, in case it was not parameterized on the gear revolution geometries

• Gear pair configuration

• Output-to-input direction

• Backlash

• Stiffness

• Damping


• Ratio

Adams/DrivelineGear Pairs

36

Request Definition

Result name: gear_states_1 (input gear/shaft) and gear_states_2 (output gear/shaft)

Gear Parameters

Component:Component

name:Component

units: Definition:

F2 angle angle The angle between the two parts (gear and shaft).

F3 angular_velocity angular velocity The relative velocity between the two parts (gear and shaft).

F4 torque torque Rotational force exerted by the synchronizer element.

37Hypoid Gear Forces

Hypoid Gear Forces

This component represents hypoid gear forces. It consists of the following objects:

• A general force featuring the actions and reactions between the ring gear and pinion gear.

• Two differential equations to calculate gear angular error and angular error integral.

Learn about hypoid gear forces:

• Creating or Modifying Hypoid Gear Forces

• About Hypoid Gear Forces

• Example Hypoid Gear-Forces Property File

Creating or Modifying Hypoid Gear ForcesTo create or modify hypoid gear forces:

1. From the Driveline Components menu, point to Hypoid Gear Force, and then select New/Modify.

2. Press F1 and then follow the instructions in the dialog box help for Hypoid Gear Force.

3. Select OK.

Adams/DrivelineHypoid Gear Forces

38

About Hypoid Gear ForcesTheoretical Background


The forces exchanged between ring gear and pinion gear at the mesh point can be evaluated as shown in the following tables.

Front and Rear Axles in Drive Conditions

Front and Rear Axles in Coast Conditions

Axial force: Separating force:

PINION

GEAR

Axial force: Separating force:

PINION

GEAR


40

The gear mesh point position can be calculated as:

Adams/Driveline implements the component with general forces using, as reference, frame markers positioned at the gear mesh point. It calculates the location and orientation of these reference markers into the component using data you provide.

• x, y, z = Mesh point location

• p, = Pinion face, gear root angles

• = Gear offset angle

• p, g = Pinion and gear offset angles

• = Pressure angle

• p, g = Pinion and gear spiral angles

• Ap, Ag = Pinion and gear mean cone distances

• E = Offset of gear and pinion centerlines

• Rp, Rg = Pinion and gear mean radius

• z' = Gear pitch apex beyond crossing point


The following figure shows how you must orient reference frames for a correct evaluation of gear forces:

You must create the case reference frame on the intersection of the z-axis of the pinion reference frame and the z-axis of the ring reference frame. Adams/Driveline uses the case reference frame to locate the marker at the gear contact point.

In the Template Builder, you can specify the parameters as shown next.

Hypoid Gear Parameters


Pinion gear I part Rigid part modeling the pinion

Pinion gear J part Rigid part to which pinion part is connected

Ring gear I part Rigid part modeling the ring gear

Ring gear J part Rigid part to which ring gear is connected

Pinion reference frame At pinion gear joint location, z-axis pointing towards pinion apex

Ring reference frame At ring gear joint location, z-axis pointing towards ring apex

Case reference frame At crossing point of ring reference frame and pinion reference frame

Stiffness Gear forces stiffness

Damping Gear forces damping


42

Example Hypoid Gear-Forces Property File$--------------------------------------------------MDI_HEADER

[MDI_HEADER] FILE_TYPE = 'hyp' FILE_VERSION = 4.0 FILE_FORMAT = 'ASCII' $--------------------------------------------------UNITS [UNITS] LENGTH = 'mm' ANGLE = 'degrees'FORCE = 'newton' MASS = 'kg' TIME = 'second' $--------------------------------------------------GEAR_PARAMETERS[GEAR_PARAMETERS] PINION_N_OF_TEETH = 133 PRESSURE_ANGLE = 15.633 PINION_OFFSET = 38.1 PINION_MEAN_CONE_DISTANCE = 120.0404 PINION_PITCH_ANGLE = 20.1 PINION_MEAN_SPIRAL_ANGLE = 48.533 RING_N_OF_TEETH = 43 RING_MEAN_CONE_DISTANCE = 102.0572 RING_PITCH_ANGLE = 68.5333

Differential location Front or rear

Property file Stores the hypoid gear properties (see Hypoid Gear Example Property File).

• PINION_N_OF_TEETH

• PRESSURE_ANGLE

• PINION_OFFSET

• PINION_MEAN_CONE_DISTANCE

• PINION_PITCH_ANGLE

• PINION_MEAN_SPIRAL_ANGLE

• RING_N_OF_TEETH

• RING_MEAN_CONE_DISTANCE

• RING_PITCH_ANGLE

• RING_MEAN_SPIRAL_ANGLE

• RING_OFFSET_ANGLE

• RING_FACE_WIDTH

• RING_PITCH_APEX



RING_MEAN_SPIRAL_ANGLE = 27.20 RING_OFFSET_ANGLE = 20.0667 RING_FACE_WIDTH = 32.512 RING_PITCH_APEX = 3.556

Adams/DrivelineLimited Slip Differentials

44

Limited Slip Differentials

This component is described as a force acting between differential side gears and the differential casing. No additional parts are modeled.

Learn about limited slip differentials:

• Creating or Modifying Limited Slip Differentials

• About Limited Slip Differentials

Creating or Modifying Limited Slip DifferentialsTo create or modify a limited slip differential:

1. From the Driveline Components menu, point to Limited Slip Differential, and then select New/Modify.

2. Press F1 and then follow the instructions in the dialog box help for Limited Slip Differential.

3. Select OK.

About Limited Slip DifferentialsA limited slip differential can be:

• Viscous - You must select a property file containing the characteristic describing the way the torque is transferred from one side to the other if one wheel starts to spin. During the simulation, as soon as one wheel start to spin the torque applied at that wheel decreases and is transferred to the other wheel. The sum of torques applied at both wheels is kept constant and equal to the torque exerted by the engine.

• Clutch-pack - You can simulate the behavior of a clutch device which prevents one wheel from spinning. Input parameters are friction coefficient, friction arm, preload, ramp angle of the gear, side gear radius, and the revolute joints between side gears and the differential casing. This component can evaluate thrust forces due to gear contacts, and can use these forces to calculate the friction forces in the clutch.

45Limited Slip Differentials

• Torque-sensing - You must specify the bias ratio and the torque and speed thresholds at which the differential starts transferring torque. You must also specify an Adams variable which defines the input torque. (In some cases, this variable is replaced by an input communicator pointing to an Adams variable defined in another subsystem.) Select Torsen Type A/B to represent an even torque split between the differential outputs. Select Torsen Type C to represent a center differential with a user-specified Nominal Torque Split. The percentage of torque applied to the first and second gear parts must add up to 100. For example, if user enter 30 for First Ratio, Adams/Driveline will suggest 70 for the Second Ratio.

The expression of the differential torque is as follows:

Diff Torque = Input Torque * Scale / Kinematic Ratio * STEP(Dw, -Speed Threshold, -1, Speed Threshold, 1)*

STEP(Input Torque, -Torque Threshold, -1, Torque Threshold, 1)

This torque function is applied to both halves of the differential. The difference in sign is handled by the definitions of the I and J markers of the two torques.

where:

• Scale = 0.5 * (bias -1) / (bias + 1)

• Kinematic Ratio = First Ratio/Second Ratio

• Dw = difference in angular velocity between the first and second parts

You can deactivate the limited slip differential using the Adams/Driveline Activity Wizard.


• Property file (for viscous-sensing limited slip differentials)

• Friction (for clutch-pack limited slip differentials)

• Friction arm (for clutch-pack limited slip differentials)

• Preload (for clutch-pack limited slip differentials)

• Ramp (for clutch-pack limited slip differentials)

• Side gear radius (for clutch-pack limited slip differentials)

• Bias ratio (for torque-sensing limited slip differentials)

• Torsen type (for torque-sensing limited slip differentials)

• Torque threshold (for torque-sensing limited slip differentials)

• Speed threshold (for torque-sensing limited slip differentials)

• First ratio (for Type C torque-sensing limited slip differentials)

• Second ratio (for Type C torque-sensing limited slip differentials)

Adams/DrivelineLimited Slip Differentials

46

Request Definition


• Type

• Property file

• Bias ratio

• Torque threshold


name:Component

units: Definition:

F2 left angular velocity RPM The angular velocity of the left side gear.

F3 right angular velocity RPM The angular velocity of the right side gear.

F4 left force torque Torque applied between the left side gear and the differential casing.

F6 right force torque Torque applied between the right side gear and the differential casing.

47Planetary Gears

Planetary Gears

This component represents a planetary gear.

Learn about planetary gears:

• Creating or Modifying Planetary Gears

• About Planetary Gears

Creating or Modifying Planetary GearsTo create or modify planetary gears:

1. From the Driveline Components menu, point to Planetary Gear, and then select New/Modify.

2. Press F1 and then follow the instructions in the dialog box help for Planetary Gear.

3. Select OK.

About Planetary GearsYou define a planetary gear using the following parts:

• Sun part (lp sun)

• Ring part

• Carrier part

These parts are attached to the powerplant by the following joints:

• Sun joint (to powerplant)

• Ring joint (to powerplant)

Adams/DrivelinePlanetary Gears

48

• Carrier joint (to powerplant)

A reference frame determines the planetary gear axis construction frame.

The planetary gear properties are stored in a property file.

The planetary gear connects the sun part to a sun_lash part (and the ring part to a ring_lash part). The sun_lash part is connected to the sun part through a revolute joint and a torque to model the gear lash and stiffness properties (defined in a property file). The same modeling technique is used for the ring. The torque expression uses the backlash formulation as explained for rotational backlash.

The planetary gear ratio is set between sun_lash part, ring part, and carrier part through a coupler, using the formula:

(r1 * q1) + (r2 * q2) + (r3 * q3) = 0,

where r1, r2, and r3 are the scale factors for the three joints, and for each joint, q1, q2, and q3, are rotational displacements of the joint I marker with respect to the joint J marker.

Therefore, using the Willis formula, we can determine that the coupler factors are:

sun number of teeth -> applied to the sun joint

(sun number of teeth + ring number of teeth) -> applied to the carrier joint

ring number of teeth -> applied to the ring joint

In the Standard Interface you can vary the property file.

Request Definition



name:Component

units: Definition:

F2 Sun_rpm angular velocity Angular velocity of the sun with respect to the powerplant.

F3 Ring_rpm angular velocity Angular velocity of the ring with respect to the powerplant.

F4 Carrier_rpm angular velocity Angular velocity of the carrier with respect to the powerplant.

49Planetary Gears



Property file (<db_name>/torque_converters.tbl)

Component:Component

name:Component

units: Definition:

F2 Sun_backlash angle Angular lash between sun and sun lash parts.

F3 Ring_backlash angle Angular lash between ring and ring lash parts.

F6 Sun_torque torque Torque acting between sun and sun lash parts.

F7 Ring_torque torque Torque acting between ring and ring lash parts.

Adams/DrivelineRavigneaux Gears

50

Ravigneaux Gears

This component represents a ravigneaux gear.

Learn about ravigneaux gears:

• Creating or Modifying Ravineaux Gears

• About Ravigneaux Gears

Creating or Modifying Ravineaux GearsTo create or modify ravineaux gears:

1. From the Driveline Components menu, point to Ravineaux Gear, and then select New/Modify.

2. Press F1 and then follow the instructions in the dialog box help for Ravigneaux Gear.

3. Select OK.

About Ravigneaux GearsYou define a ravigneaux gear using the following parts:

• Long pinion sun part (lp sun)

• Short pinion sun part (sp sun)

• Ring part

• Carrier part

These parts are attached to the powerplant by the following joints:

• Long pinion sun joint (to powerplant)

51Ravigneaux Gears

• Short pinion sun joint (to powerplant)

• Ring joint (to powerplant)

• Carrier joint (to powerplant)

A reference frame determines the ravigneaux gear axis construction frame.

The ravigneaux gear properties are stored in a property file.

The ravigneaux gear connects the two sun parts to the two sun_lash parts (and the ring part to a ring_lash part). The sun_lash part is connected to the sun part through a revolute joint and a torque to model the gear lash and stiffness properties (defined using a property file). The same model technique is used for the ring. The torque expression uses the backlash formulation, as explained for rotational backlash.

The ravigneaux gear ratio is set between lp sun lash part, sp sun lash part, ring part, and carrier part through two couplers using the formula:

(r1 * q1) + (r2 * q2) + (r3 * q3) = 0,

where r1, r2, and r3 are the scale factors for the three joints, and for each joint, q1, q2, and q3 are rotational displacements of the joint I marker with respect to the joint J marker.

Therefore, using the Willis formula, we can determine that the coupler factors are:

COUPLER 1 (sp_planetary_gear_ratios), acting between sp sun lash joint, carrier joint and ring lash joint:

Sp sun number of teeth -> applied to the sun joint

(- sp sun number of teeth + ring number of teeth) -> applied to the carrier joint

- ring number of teeth -> applied to the ring joint

COUPLER 2 (lp_planetary_gear_ratios), acting between lp sun lash joint, carrier joint, and ring lash joint:

lp sun number of teeth -> applied to the sun joint

- (lp sun number of teeth + ring number of teeth) -> applied to the carrier joint

ring number of teeth -> applied to the ring joint

In the Standard Interface you can vary the property file.

Adams/DrivelineRavigneaux Gears

52

Request Definition






name:Component

units: Definition:

F2 Sp_Sun_rpm angular velocity Angular velocity of the short pinion sun with respect to the powerplant.

F3 LP_sun_rpm angular velocity Angular velocity of the long pinion sun with respect to the powerplant.

F4 Ring_rpm angular velocity Angular velocity of the ring with respect to the powerplant.

F6 Carrier_rpm angular velocity Angular velocity of the carrier with respect to the powerplant.


name:Component

units: Definition:

F2 Sp_Sun_backlash angle Angular lash between the short pinion sun and its lash parts.

F3 Lp_Sun_backlash angle Angular lash between the long pinion sun and its lash parts.

F4 Ring_backlash angle Angular lash between the ring and ring lash parts.

F6 SP_Sun_torque torque Torque acting between the short pinion sun and its lash parts.

F7 LP_Sun_torque torque Torque acting between the long pinion sun and its lash parts.

F8 ring_torque torque Torque acting between the ring and ring lash parts.

53Ride Wheels

Ride Wheels

The tire component consists of a rim and a ring.

Learn about ride wheels:

• Creating or Modifying Ride Wheels

• About Ride Wheels

• Example Ride-Wheel Property File

Creating or Modifying Ride WheelsTo create or modify ride wheels:

1. From the Driveline Components menu, point to Ride Wheel, and then select New/Modify.

2. Press F1 and then follow the instructions in the dialog box help for Ride Wheels.

3. Select OK.

About Ride WheelsThe tire model consists of two parts:

• Rim - Is connected to the suspension hub during the assembly.

• Ring - Is connected to the rim with a vertical spring damper, a longitudinal spring damper, and a torsion spring damper to describe the elasticity of the tire itself.

The rim and ring parts are also connected to each other with a planar joint, which constrains the two parts to moving in the global XZ plane.

The ring is then connected to another part, named road, with a vertical force. This force is used to evaluate traction forces exerted between the ring and the road in case a driving/braking torque is applied to the

Adams/DrivelineRide Wheels

54

driveline model. The traction force is applied at the wheel center. Therefore, a torque is needed equal to the traction torque times the loaded tire radius.

If we call the vertical force between the ring and the road Fz, then we can say that the traction force, Fx, is equal to:

Fx = m * Fz

where:

• m = road friction coefficient

• Fz = vertical load

The friction coefficient is calculated using the tire slip and the spline defining the dependency of the friction on the tire slip (see figure Friction-Slip Function). The calculation follows:m = AKISPL(slip,0, friction_spline) * friction_var

where:

• slip = tire slip

• friction_var = friction scaling function. This value is used to scale to the original friction spline, defined for a maximum friction coefficient of 1.

Friction_var is defined using an adams_variable and can be defined to change either as a function of time or traveled distance.

For example, if you want to have the friction on the front left tire go down to 0.5 at time = 1 sec and then back to 1 at time = 2.5 with a transition time of 0.5 seconds, the expression for front left friction_var is as follows:

STEP(TIME,1,1,1,5,0.5) + STEP(TIME, 2, 2.5, 0, 0.5)

You can set this dependency using a specific dialog box from the Adams/Driveline Standard Interface, prior to submitting the Analysis. This dialog box allows you to set any kind of expression for the friction coefficient, for an expression similar to the one explained above. You also have the graphical support that gives you feedback on the shape of function you are using.

To access the dialog box, from the Simulate menu, point to Full-Vehicle Analysis, point to Environmental Conditions, and then select Road Friction.

An Adams variable named traveled_distance automatically evaluates the distance traveled by the full-vehicle model. If friction has to be defined as a function of the traveled distance, the expression could be something like:

STEP(VARVAL(traveled_distance),1,1,1,5,0.5) + STEP(VARVAL(traveled_distance), 2, 2.5, 0, 0.5)

55Ride Wheels

Friction-Slip Function

Adams/Driveline evaluates the tire slip according to the following formula (note that slip will be always between -1 and 1):

slip = MAX(MIN((V - wr)/ABS(v), 1), -1)

where:

• V = longitudinal speed of the car

• w = rotational velocity of the wheel

• r = loaded radius of the wheel (DZ(rim_cm, road))

Note that the reason why the ring part is connected to the road instead of the ground is because this modeling technique allows you to put vertical and longitudinal actuators between the road and the ground. This makes it possible to apply imposed motions to the full-vehicle model, such as known road profiles or frequency sweep profiles.

The interposition of a rotational spring damper between the rim and the ring part is very important for those analyses in which it is important to capture natural frequencies of the tire, such obstacle-passing maneuver or tip in - tip out analyses.

Request Definition


name:Component

units: Definition:

F2 Longitudinal slip none The longitudinal slip of the tire.

F3 Omega RPM The angular velocity of the tire.

Adams/DrivelineRide Wheels

56


Property file

Example Ride-Wheel Property File

$--------------------------------------------------MDI_HEADER[MDI_HEADER] FILE_TYPE = 'rti' FILE_VERSION = 2.0 FILE_FORMAT = 'ASCII'(COMMENTS) {comment_string} 'Tire - Ride Tire' $--------------------------------------------------UNITS [UNITS] LENGTH = 'mm' ANGLE = 'degrees' FORCE = 'newton' MASS = 'kg' TIME = 'second' $--------------------------------------------------MODEL [MODEL] PROPERTY_FILE_FORMAT = 'RIDE' $--------------------------------------------------DIMENSION[DIMENSION] RADIUS = 300WIDTH = 300 ASPECT_RATIO = 0.55 RIM_RADIUS = 190RIM_WIDTH = 139 $--------------------------------------------------TIRE_PARAMETERS[TIRE_PARAMETERS] STIFFNESS = 9e5 DAMPING = 1e4 TORSION_STIFFNESS = 6e4 TORSION_DAMPING = 1e1

$---------------------------------------------------RING_PARAMETERS[RING_PARAMETERS] MASS = 4.5 Ixx = 1 IYY = 1 IZZ = 1 $------------------------------------------------FRICTION_vs_SLIP[FRICTION_vs_SLIP] { slip_speed friction } -1.0 -0.6508 -0.95 -0.6624 -0.91 -0.6799

F4 Traction force Traction force exerted by the tire.

F6 Vertical force force Vertical load on the tire.


name:Component

units: Definition:

57Ride Wheels

-0.87 -0.6945 -0.83 -0.7061 -0.79 -0.7265 -0.75 -0.7497 -0.7 -0.7673 -0.666 -0.7847 -0.62 -0.8021 -0.58 -0.8168 -0.54 -0.8312 -0.5 -0.8487 -0.45 -0.8662-0.41 -0.8837 -0.375 -0.9012 -0.33 -0.9274 -0.29 -0.9477 -0.25 -0.9639 -0.2 -0.9869-0.166 -0.9927 -0.125 -1.0007-8.0E-02 -0.9777 -4.0E-02 -0.8092 0.0 0.0 4.0E-02 0.8092 8.0E-02 0.9777 0.125 1.00070.166 0.99270.2 0.98690.25 0.9639 0.29 0.9477 0.33 0.9274 0.375 0.90120.41 0.88370.45 0.86620.5 0.84870.54 0.83120.58 0.81680.62 0.8021 0.666 0.7847 0.7 0.7673 0.75 0.7497 0.79 0.7265 0.83 0.70610.87 0.69450.91 0.67990.95 0.6624 1.0 0.6508

Adams/DrivelineTorque Converters

58

Torque Converters

This component allows you to define a torque converter in the driveline model.

Learn about torque converters:

• Creating or Modifying Torque Converters

• About Torque Converters

• Example Torque-Converter Property File

Creating or Modifying Torque ConvertersTo create or modify torque converters:

1. From the Driveline Components menu, point to Torque Converter, and then select New/Modify.

2. Press F1 and then follow the instructions in the dialog box help for Torque Converter.

3. Select OK.

About Torque ConvertersYou define torque converters using three parts:

• Impeller (input shaft)

• Turbine (output shaft)

• Case

On these three parts, you apply (at least) three different forces:

• Impeller drag

• Turbine torque

59Torque Converters

• Converter damping

• Lockup clutch torque (optional)

These forces are defined according to the content of the property file you specify.

The property file stores two curves:

• Torque ratio versus speed ratio

• Capacity factor versus speed ratio

Capacity factor is defined as input speed divided by the square root of the input torque, as a function of speed ratio. The units are angular_velocity/SQRT(torque), where the units of angular_velocity and torque are defined in the property file.

The following figures show sample plots for these two curves.

Torque Ratio


60

Capacity Factor

The torque converter includes a clutch part that is connected to the turbine with a torsion spring. The clutch allows the direct engagement of the impeller to the turbine when the torque converter change-over point is reached. You can define the clutch expression by either specifying the change-over point (the speed ratio at which the clutch must be engaged) or a clutch expression as a function of time.

Adams/Driveline uses the following formulas to evaluate action and reaction torque:

Impeller drag (acting between impeller and turbine):

direction * STEP5(speed_ratio,0.995,1,1.005,-1) * (1/ucf_angle_to_radians*WZ(I,J,J) / Capacity_factor)**2

Turbine torque (acting between turbine and case):

direction * - impeller_drag * AKISPL(speed_ratio,0, torque_ratio,0)

Converter damping (acting between turbine and clutch part):

-clutch_torsional_stiffness*AZ(I,J) - clutch_torsional_damping*WZ(I,J,J)

Lockup clutch (acting between impeller and clutch part) torque:

clutch switch * clutch torque

You can define the clutch torque either as a user-entered function of time or as a change-over point. For the case of a change-over point, the clutch torque function will be:

STEP5(speed_ratio, change_over_point - .05, 0, change_over_point + .05, -clutch_slip_gain * WZ(I,J,J))

61Torque Converters

In the Standard Interface, you can vary the property file, direction, and lockup clutch actuation method.

Request Definition

Result name: torque_cvtr_results



Example Torque-Converter Property File<adriveline_shared>/torque_converters.tbl/mdi_0001.tcf

$----------------------------------------------------------MDI_HEADER[MDI_HEADER] FILE_TYPE = 'tcf' FILE_VERSION = 4.0 FILE_FORMAT = 'ASCII'$---------------------------------------------------------------UNITS[UNITS] LENGTH = 'foot'

Component name: Component units: Definition:

impeller_rpm RPM Angular velocity of the impeller (input shaft) with respect to the torque converter case.

turbine_rpm RPM Angular velocity of the turbine (output shaft) with respect to the torque converter case.

conv_clutch_rpm RPM Angular velocity of the clutch (output shaft) with respect to the turbine.

speed_ratio no units The ratio of the turbine speed over impeller speed.

impeller_torque torque Torque on the impeller (input shaft) with respect to the torque converter case.

turbine_torque torque Torque on the turbine (output shaft) with respect to the torque converter case.

conv_clutch_torque torque Torque on the clutch (output shaft) with respect to the turbine.

K_factor angular velocity / SQRT(torque)

The torque converter capacity factor.

torque_ratio no units The ratio of the turbine torque over impeller torque.


62

FORCE = 'pound_force' ANGLE = 'deg' MASS = 'pound_mass' TIME = 'sec'$---------------------------------------------TORQUE_CONVERTER_HEADER[TORQUE_CONVERTER_HEADER] MODEL = 'torque_ratio_capacity_factor' CLUTCH_ACTIVE = 'yes'$--------------------------------------------------------------CLUTCH[CLUTCH]$ clutch mass & inertia properties MASS = 2.2 IXX = 1 IYY = 1 IZZ = 2$ clutch connection properties$ to turbine: CLUTCH_TORSIONAL_STIFFNESS = 18 CLUTCH_TORSIONAL_DAMPING = 18$ to impeller: CHANGE_OVER_POINT = 0.8 CLUTCH_SLIP_GAIN = 0.6$--------------------------------------------------------TORQUE_RATIO[TORQUE_RATIO]{speed_ratio torque_ratio}-5.000 1.769-2.000 1.769-1.000 1.769 0.000 1.769 0.123 1.674 0.251 1.573 0.382 1.457 0.509 1.348 0.636 1.241 0.736 1.159 0.809 1.094 0.868 1.038 0.895 1.012 0.903 1.009 0.908 1.009 0.914 1.009 0.918 1.009 0.922 1.009 0.926 1.009 0.930 1.009 0.934 1.009 0.937 1.007 0.940 1.007 0.943 1.007 0.945 1.007 0.948 1.007 0.950 1.007 0.953 1.006 0.955 1.006

63Torque Converters

0.957 1.004 0.959 1.004 0.961 1.004 0.963 1.004 0.965 1.004 0.996 1.004 0.997 1.004 0.998 1.004 1.001 1.130 1.006 1.120 1.013 1.058 1.019 1.040 1.020 1.030 1.025 1.025 1.032 1.021 1.052 1.015 1.100 1.012 1.208 1.010 1.258 1.009 1.328 1.006 1.423 1.005 1.592 1.006 1.808 1.004 2.166 1.005 2.833 1.006 4.172 1.005 8.283 1.005$-----------------------------------------------------CAPACITY_FACTOR[CAPACITY_FACTOR]{speed_ratio capacity_factor}-5.000 956.4-2.000 956.4-1.000 956.40.000 956.40.123 945.60.251 935.40.382 927.00.509 928.80.636 931.80.736 967.20.809 1026.00.868 1093.20.895 1127.40.903 1183.20.908 1241.40.914 1300.20.918 1359.00.922 1417.20.926 1475.40.930 1533.00.934 1591.20.937 1650.00.940 1707.60.943 1766.4


64

0.945 1824.60.948 1882.80.950 1940.40.953 1996.80.955 2054.40.957 2112.60.959 2170.80.961 2229.00.963 2285.40.965 2343.60.996 7432.80.997 30000.00.998 210000.01.001 210000.01.006 7407.01.013 5301.01.019 4350.01.020 3771.61.025 3411.01.032 3050.41.052 2674.21.100 2325.61.208 2056.81.258 1929.61.328 1812.61.423 1697.41.592 1624.21.808 1534.82.166 1467.62.833 1444.84.172 1422.68.283 1413.0

65Torsion Springs

Torsion Springs

This component represents a simple torsional spring-damper connector. A torsion spring describes a rotational connection between two parts. Adams/Driveline models the torsion spring with a single-component force that works with the relative angular displacement and the relative angular velocity. Adams/Driveline creates a revolute joint between the I and J parts.

Learn about torsion springs:

• Creating or Modifying Torsion Springs

• About Torsion Springs

Creating or Modifying Torsion SpringsTo create or modify a torsion spring:

1. From the Driveline Components menu, point to Torsion Spring, and then select New/Modify.

2. Press F1 and then follow the instructions in the dialog box help for Torsion Spring.

3. Select OK.

About Torsion SpringsThe elements that the torsion spring creates are:

• Revolute joint connecting the two parts

• Rotational single-component force connecting acting between the two parts

• Request

The torsion spring force is defined as follows:

Spring Type: Linear

Torque= - Stiffness * AZ(I mar, J mar) - Damping * WZ(I mar, J mar, I mar)


Adams/DrivelineTorsion Springs

66

Spring Type: Non-linear

T = (-AKISPL(AZ(I mar, J mar), 0, spline) - Damping * (WZ(I mar, J mar, I mar))) -STEP(WZ(I mar, J mar, J mar), -1, -Hysteresis * 0.5, 1, Hysteresis * 0.5)

where:


• Stiffness = Torsional stiffness

• Damping = Torsional damping

• Hysteresis = Total hysteresis torque

• I mar = Marker belonging to the I part

• J mar = Marker belonging to the J part

In the Standard Interface, you can vary values for torsional stiffness and damping for a Linear torsion spring. For a Non-linear torsion spring, you can vary values for damping, hysteresis, and property file. The property file for a non-linear torsion spring contains a curve of torque vs. angle. You can also remove the compliance of the torsion spring from your system by setting Lock = yes.

Request Definition

Result name: <torsion spring name>_data


• Property file

• Spring type

Note: The following applies to those using these components for shaft elasticity: In the create/modify dialog box in the Template Builder and in the modify dialog box in the Standard Interface (learn about the Interface Modes), you can access an additional dialog box that helps you select "first attempt" values for Stiffness and Damping based upon the material, length, and section type of the shaft. This option can be very useful in early stage studies in which adequate data are not yet available.


name:Component

units: Definition:

F2 angular angle The angle between the two parts connected with the torsion spring.

F3 angular velocity angular velocity The angular velocity between the two parts connected by the torsion spring.

F4 torque torque Torque exerted between the two parts connected by the torsion spring.

67Torsion Springs

• Stiffness

• Damping

• Hysteresis

• Lock

Example non-linear torsion spring property file:

<adriveline_shared>/complex_springs.tbl/mdi_0001.tsf

$----------------------------------------------------------MDI_HEADER[MDI_HEADER] FILE_TYPE = 'dpr' FILE_VERSION = 4.0 FILE_FORMAT = 'ASCII'$---------------------------------------------------------------UNITS[UNITS] LENGTH = 'mm' ANGLE = 'degrees' FORCE = 'newton' MASS = 'kg' TIME = 'second'$---------------------------------------------------------------CURVE[CURVE]{ angular_displacement torque} -7.000E+00 -5.000E+05 -6.000E+00 -3.500E+05 -5.000E+00 -2.300E+05 -4.000E+00 -1.500E+05 -3.000E+00 -9.000E+04 -2.000E+00 -6.000E+04 -1.000E+00 -3.000E+04 +0.000E+00 +0.000E+00 +1.000E+00 +3.000E+04 +2.000E+00 +6.000E+04 +3.000E+00 +9.000E+04 +4.000E+00 +1.500E+05 +5.000E+00 +2.300E+05 +6.000E+00 +3.500E+05 +7.000E+00 +5.000E+05

Adams/DrivelineUnbalanced Mass

68

Unbalanced MassThis component describes an unbalanced mass by its unbalanced momentum.

Learn about unbalanced mass:

• Creating or Modifying Unbalanced Mass

• About Unbalanced Mass

Creating or Modifying Unbalanced MassTo create or modify unbalanced mass:

1. From the Driveline Components menu, point to Unbalanced Mass, and then select New/Modify.

2. Press F1 and then follow the instructions in the dialog box help for Unbalanced Mass.

3. Select OK.

About Unbalanced MassAn unbalanced mass introduces an inertial out-of-balance in your model. When creating an unbalanced mass in Adams/Driveline, you fix a concentrated mass to a specified part, at a reference distance (for example, 1 mm in MMKS) from a specified coordinate system.

Adams/Driveline computes the element mass as a function of the specified unbalanced momentum:

Mass = Unbalanced Momentum / (Reference Distance)2


• Unbalanced momentum

69Viscous Coupling

Viscous Coupling

This component represents viscous coupling. A property file determines the viscous characteristics. The component consists of a rotational force acting between the two parts with the location and orientation determined by the selected construction frame. A viscous coupling describes a force-based connection between two parts. A viscous coupling exerts a torque whenever the relative angular velocity between two parts exceeds a certain value. When the relative angular velocity is zero, no torque is transmitted.

Learn about viscous coupling:

• Creating or Modifying Viscous-Coupling Components

• About Viscous-Coupling Components

• Example Viscous-Coupling Property File

Creating or Modifying Viscous-Coupling ComponentsTo create or modify a viscous-coupling component:

1. From the Driveline Components menu, point to Viscous Coupling , and then select New/Modify.

2. Press F1 and then follow the instructions in the dialog box help for Viscous Coupling.

3. Select OK.

About Viscous-Coupling ComponentsThe elements that a viscous-coupling component creates are:

• General spline based on a property file

• Torque function of the 2D general spline

• Cylinder graphics

• Request

The viscous coupling force is defined as follows:

Torque=-SIGN(akispl(ABS(WZ(I mar, J mar, J mar)),0, Spline), WZ(I mar, J mar, J mar))

Adams/DrivelineViscous Coupling

70

where:


• Spline = The two-dimensional spline that defines the slip-speed versus torque characteristic

• I mar = Marker belonging to the I part

• J mar = Marker belonging to the J part

In steady state conditions, equal velocities of the two half shafts produce a 0.0 torque.

In the Standard Interface, you can vary values for the property file, which effectively determines the torque/slip-speed characteristic.

Request Definition

Result name: vcoupling_states


Property file (<db_name>/differentials.tbl) (see Viscous Coupling Example Property File)

Example Viscous-Coupling Property File$--------------------------------------------------MDI_HEADER

[MDI_HEADER]FILE_TYPE = 'dif' FILE_VERSION = 4.0 FILE_FORMAT = 'ASCII'$--------------------------------------------------UNITS[UNITS] LENGTH = 'mm' ANGLE = 'degrees' FORCE = 'newton'MASS = 'kg' TIME = 'second'$--------------------------------------------------DIFFERENTIAL[DIFFERENTIAL] { slip_speed torque}0.0 0.04.1 868.0556 8.3347 2.2222 12.5 7812.5 16.6 13888


name:Component

units: Definition:

F2 angular displacement

angle The angle between the two parts connected with the vcoupling element.

F3 velocity velocity Relative angular velocity.

F4 force force Force exerted by the viscous coupling element.

71Engine Map Property File

Engine Map Property File$--------------------------------------------------MDI_HEADER

[MDI_HEADER]FILE_TYPE = 'pwr' FILE_VERSION = 1.0 FILE_FORMAT = 'ASCII'$--------------------------------------------------UNITS [UNITS] (BASE){length force angle mass time} 'mm' 'newton' 'degree' 'kg' 'sec'{unit_type length force angle mass time conversion}'Nmm' 1 1 0 0 0 1.0 $--------------------------------------------------ENGINE[ENGINE] (Z_DATA) {throttle} 0.0 1.00 (XY_DATA) {engine_speed <no_units> torque <Nmm>} 0 0 0 500 -20000

80000 1000 -42000 135000 1500 -44000 2000002000 -46000 2450002500 -48000 2630003000 -50000 310000 3500 -50000 3580004000 -50000 4040004500 -50000 455000 5000 -50000 475000 5500 -50000 4850006000 -50000 4680006250 -50000 4620006500 -52000 4550006750 -56000 4270007000 -60000 3700007500 -64000 259000

Adams/DrivelineExample Torque-Loadcase File

72

Example Torque-Loadcase File

$-----------------------------------------------------MDI_HEADER[MDI_HEADER]FILE_TYPE = 'tor'FILE_VERSION = 1.0FILE_FORMAT = 'ascii'$-----------------------------------------------------UNITS[UNITS]LENGTH = 'mm'FORCE = 'newton'ANGLE = 'deg'MASS = 'kg'TIME = 'sec'$-----------------------------------------------------MODE[MODE]$ time_distance_mode = time, distanceTIME_DISTANCE_MODE = 'time'$-----------------------------------------------------DATA[DATA]$COLUMN: input type: type of input data: $ (c1) time/distance time or distance traveled$ (c2) torque torque (XY_DATA){ time_dist torque }0 0.00.01 0.00.02 0.00.03 0.00.04 0.00.05 0.00.06 0.00.07 0.00.08 0.00.09 0.00.1 0.00.11 13388.20.12 42060.13 14909.10.14 14906.60.15 13378.10.16 16444.90.17 14918.30.18 72670.19 16438.30.2 8787.9

Working with Templates

Adams/DrivelineIntroducing the Templates

2

Introducing the Templates Your template-based product's library includes a variety of templates. Templates define the topology, Major Roles, and default parameters for Subsystems. This tab includes template information that is specific to your product.

For general template information, as well as information about the other files that make up model architecture, see Building Models.

Running Analyses

Adams/DrivelineOverview of Analyses

2

Overview of AnalysesAdams/Driveline allows you to create virtual prototypes of vehicle subsystems, and analyze the virtual prototypes much like you would analyze the physical prototypes.

Adams/Driveline lets you analyze virtual prototypes of full vehicles. Using Adams/Driveline, you can:

• Easily modify the geometry and the properties of the components of your subsystems.

• Select from a standard set of vehicle maneuvers to evaluate the dynamic characteristics of your virtual prototype.

• View the vehicle states and other characteristics through plots.

When setting up an analysis in Adams/Driveline, you specify the following:

• The virtual prototype to be tested - You specify the virtual prototype by opening or creating an assembly that contains the appropriate components, or subsystems, that make up the prototype. For example, you create a suspension assembly containing suspension and steering subsystems.

• The kind of Analysis you'd like performed - You specify the test or analysis by selecting one from the Adams/Car Simulate menu. There are two major types of analyses: suspension and full-vehicle.

• The analysis inputs to be used - You specify the inputs to the analysis by typing them directly into an analysis dialog box or by selecting a loadcase file that contains the desired inputs from an Adams/Car database.

After specifying the prototype assembly and its analysis, Adams/Driveline, like your company’s testing department, applies the inputs that you specified and records the results. To understand how your prototype behaved during the analysis, you can plot the results. After viewing the results, you can modify the prototype and analyze it again to see if your modifications improved its behavior.

Each kind of analysis that you perform requires a minimum set of subsystems. For example, a full-vehicle analysis requires front and rear suspension subsystems, front and rear wheel subsystems, one steering subsystem, and one body subsystem. Before you can create an assembly and perform an analysis in Adams/Driveline, you must open or create the minimum set of subsystems required.

3Running AnalysesBench-Test Analysis

Bench-Test AnalysisA bench-test Analysis is a generic Adams/Driveline analysis in which you can specify an end time and the number of steps.

Adams/Driveline assumes that you have previously set the model to perform any kind of analysis. You can use this analysis any time standard analyses (such as step torque, and ramp torque) are not exactly what you want to perform.

To perform this analysis, you must first create either a full-vehicle assembly or a bench-test assembly.

To create either type of assembly:

• From the File menu, point to New, point to Assembly, and then select either Full Vehicle or Bench Test.

To set up a bench-test analysis:

1. From the Simulate menu, point to Full-Vehicle Analysis, point to Driveline Tests, and then select Bench Test.

2. Press F1 and then follow the instructions in the dialog box help for Bench-Test Analysis.

3. Select OK.

Adams/DrivelineSetting up Dropped-Clutch Analyses

4

Setting up Dropped-Clutch AnalysesA dropped-clutch Analysis is an Adams/Driveline full-vehicle analysis.

Adams/Driveline sets up the crankshaft initial velocity according to the value you specify. The clutch is initially disengaged and is engaged during the maneuver. You can either directly specify the input torque applied to the crankshaft or specify a throttle value and an engine property file. If you choose the latter option, Adams/Driveline calculates the engine torque according to the crankshaft RPM and throttle position.

To set up a dropped-clutch analysis:

1. From the Simulate menu, point to Full-Vehicle Analysis, point to Driveline Tests, and then select Dropped Clutch.

2. Press F1 and then follow the instructions in the dialog box help for Dropped-Clutch Analysis.

3. Select OK.

5Running AnalysesSetting up Initial Condition Motions Activity Analyses

Setting up Initial Condition Motions Activity AnalysesAs explained in Setting up Initial-Velocity Analyses, Adams/Driveline creates a point motion whenever you define a force-based connection between two parts. You can use this point motion to make the entire driveline behave as a kinematic system, so it can inherit the initial rotational velocity from the tires. Before running the dynamic analysis, Adams/Driveline automatically deactivates initial condition motions.

Deactivating Point Motions

In some instances, one or more point motions can cause the system to be overconstrained. For example, when creating a clutch assembly, the friction disk is typically constrained both to the flywheel and to the pressure plate with a clutch force element, and to the hub of friction disk with a torsion spring damper. In this situation, there are three point motions but only two are needed to fully constrain the model. You can deactivate one of the point motions between the friction disk and flywheel, or between the friction disk and the pressure plate.

To deactivate a point motion:

1. Open your assembly in Adams/Driveline.

2. From the Tools menu, select IC Motions Activity.

3. Press F1 and then follow the instructions in the dialog box help for Driveline IC Motions Status.

4. Select Close.

Adams/Driveline skips the deactivated point motions from the group called lock array, and ignores them during the initial velocity analysis.

Note: If your assembly does not use a subsystem with initial condition motions, Adams/Driveline informs you that there are no IC motions in your template. Select OK, and the Driveline IC Motions Status dialog box opens.

Adams/DrivelineSetting up Initial-Velocity Analyses

6

Setting up Initial-Velocity AnalysesIn Adams/Driveline, a control subroutine (CONSUB) called from the .acf File sets the initial longitudinal velocity of the vehicle automatically before a dynamic simulation is performed. You specify the initial velocity in the Submit Analysis dialog box. If the tires in the model use standard tire subroutines, the initial rotational velocity of the tires is also automatically set.

All parts constrained to the tire along the rotational axis automatically inherit the initial velocity of the tire. If a part with an initial rotational velocity is not constrained to another part along the rotational axis, the second part will not inherit the initial rotational velocity from the first part. For example, suppose you have a drive shaft consisting of an inner and an outer shaft. The two shafts might be connected to each other with a rotational spring damper, which is a force-based connection (not a constraint). A way around this problem is to temporarily constrain all rotational parts along the rotational axis while Adams is calculating the initial velocity. Before you submit the dynamic Analysis, you must remove (deactivate) all temporary constraints.

All Adams/Driveline components available in the Template Builder automatically include a rotational constraint (if needed). This constraint is a point motion (a motion between two markers) named ic_motion and it is set to zero and deactivated by default. All ic_motions in the model are also automatically added to a group named lock_array.

When you submit an analysis, Adams/Driveline activates all ic_motions and stores their Adams IDs in a solver array named lock_array.

In the .acf file, a second Adams/Driveline-specific CONSUB is called after the regular Adams/Car CONSUB. This CONSUB first performs an initial-condition velocity analysis and then deactivates all ic_motions found in the Solver array lock_array. After the initial-condition velocity analysis is run, all parts have a longitudinal and rotational velocity according to the initial velocity of the vehicle and tires. The next line in the .acf file could be a dynamic simulation command.

Restrictions

Note the following when running the Initial Velocity Analysis:

• If you do not use a standard tire subroutine, the Adams/Car CONSUB will not recognize the tire as a wheel part; therefore, no initial rotational velocity will be given to the tires. In this case, you must manually add an initial rotational velocity to the wheel part. If you use Adams/Driveline ride tires, the initial rotational velocity of the wheels is set automatically when the tires are created.

• If you build a model with standard Adams/Car components, Adams/Driveline will not automatically create the ic_motion. You can create the ic_motion in the Template Builder by selecting the Driveline Components menu, pointing to Advanced, and then selecting IC Motions Create.

• Currently, the procedure of setting initial rotational velocity only works for Adams/Driveline-specific analyses. This is due to the specific set-up macro being called from a submit macro.

7Running AnalysesSetting up Initial-Velocity Analyses

• If you manually specify initial rotational velocity on two parts that are constrained to each other, Adams/Driveline will calculate the average initial rotational velocity and use it for both parts (and all parts constrained to them).

• If you are driving the model with a motion active during the initial condition analysis, the motion velocity will overwrite all initial rotational velocities set on parts constrained by the motion.

Adams/DrivelineSetting up model for Adams/Car SDI full vehicle analyses

8

Setting up model for Adams/Car SDI full vehicle analyses In this section, more detailed information is given about how to setup the powertrain/driveline model for an Adams/Car full vehicle SDI analysis, including a Quasi-Static setup. The demo model in the shared Adams/Driveline database, JEEP_RWD_SDI.asy, will serve as an example. The following topics will be discussed:

• Powertrain/driveline communicators in SDI testrig

• General information about Quasi-Static setup analysis in Adams/Car

• Preparing Adams/Driveline model for Quasi-Static setup

• Implementation in shared Adams/Driveline SDI vehicle model

Powertrain/driveline communicators in SDI testrigIn order to communicate with the Adams/Car full vehicle SDI testrig, a number of input communicators has to be fed to it. In the section “Working with Communicators”, all input communicators to the SDI testrig are listed, but in Table 1 only those that are related to the powertrain/driveline are presented. The last column shows the communicators which are the minimum requirement for running Driving Machine closed loop events (referred to as “machine” controlled events). The other communicators are only needed for the Driving Machine SmartDriver events. In these events a low degree of freedom (DOF) vehicle model pre-calculates a speed trajectory profile based on the vehicle limit values. The low DOF vehicle model needs additional information about the full vehicle and powertrain properties.

Table 1 SDI testrig powertrain/driveline communicators

The input communciator:

Belongs to the class:

From minor role: Receives:

Min. requirement for Driving machine

closed loop events:

cis_crankshaft_ratio parameter_real any

cis_diff_ratio parameter_real any Real parameter variable for final drive ratio, from the powertrain subsystem.

cis_drive_torque_bias_front parameter_real any

cis_engine_idle_rpm parameter_real any

cis_engine_revlimit_rpm parameter_real any

cis_engine_rpm solver_variable any Adams/Solver variable for engine revolute speed, in rotations per minute, from the powertrain subsystem.

yes

9Running AnalysesSetting up model for Adams/Car SDI full vehicle analyses

General information about Quasi-Static setup analysis in Adams/CarThe objectives of a Quasi-Static setup analysis are to calculate the initial throttle demand and wheel speed of the driven wheels. The throttle demand should result in an engine torque that balances the different vehicle resistance forces (tire rolling resistance, aerodynamic drag, and so on.) at the specified initial vehicle speed and gear position.

cis_engine_speed solver_variable any Adams/Solver variable for engine revolute speed, in radians per second, from the powertrain subsystem.

yes

cis_engine_map spline any Engine torque map from powertrain subsystem.

yes

cis_max_engine_braking_torque

solver_variable any Engine torque at zero throttle yes

cis_max_engine_driving_torque

solver_variable any Engine torque at full throttle (100%)

yes

cis_max_engine_speed parameter_real any Output from powertrain subsystem (maximum engine rpm value).

yes

cis_max_gears parameter_integer

any Output from powertrain (maximum number of allowed gears).

yes

cis_min_engine_speed parameter_real any Output from powertrain subsystem (minimum engine rpm value, used for shifting strategy).

yes

cis_transmission_efficiency parameter_real any

cis_transmission_input_omega

solver_variable any The transmission input engine variable from the powertrain template. Expressed in radians per second

yes

cis_transmission_spline spline any Spline for transmission gears (output from powertrain: reduction ratios for every gear).



From minor role: Receives:

Min. requirement for Driving machine

closed loop events:


10

In the dynamic simulation, the engine torque is calculated from a three-dimensional engine map spline where the two independent parameters are throttle demand and engine speed. The throttle demand signal is received from the Driving Machine while the engine speed can be measured in the engine model by using standard Adams/Solver expressions. The engine speed can for example be evaluated by using the WZ function when a rotating crank shaft part exists in the engine model or with the VARVAL function when the engine speed is calculated in a state variable.

In the Quasi-Static setup simulation, the throttle demand is instead calculated by using a differential equation and the engine speed is calculated from the quasi-static wheel speeds and the different known ratios in the driveline (gear ratio, differential ratio, and so on.). With these two quantities calculated, the static engine torque can be derived by using the very same engine map spline that is used in the dynamic simulation.

So, how is the Quasi-Static steady state wheel speed calculated? During the static equilibrium analysis, the wheels are prevented from rotating relative to ground by using perpendicular primitive joints and the body is constrained to ground with an inline primitive joint. The throttle demand differential equation and the tire general state equations strives to zero out the reaction torque/force in these joints (since there should be no accelerations for a constant velocity). The result is that the drive torque gets balanced by the longitudinal tire forces which are dependent on the longitudinal wheel slips. Once the slip is calculated by the static solver and the initial velocity of the vehicle speed is known, the wheel speed can be evaluated. During the static solver iterations, the only unknown states are the wheel longitudinal slips of the driven wheels. All other states such as wheel speeds, engine speed, engine torque and throttle demand are therefore directly or indirectly dependent on these slip values.

Since wheel speeds can not be accessed directly in the static equilibrium analysis by using standard Adams/Solver expressions, these speed values can be evaluated by using the Adams/Solver VARSUB subroutine, VAR1004. Besides the information about I and J markers, the routine needs also information about which tire (slip) to evaluate. The call to the subroutine is done in the brake templates in the Adams/Car and Adams/Driveline shared database models. In the Adams/Driveline SDI model, JEEP_RWD_SDI.asy, the wheel speeds are also published to other subsystems via output communicators. More information about the implementation done in that shared model can be found in the section “Implementation in shared Adams/Driveline SDI vehicle model.”

Preparing Adams/Driveline model for Quasi-Static setupThe approach to support Quasi-Static setup for an Adams/Driveline model that uses an ac_dyno element to apply the engine torque, is to modify the state variable rpm_input. This state variable calculates the engine speed in revolutions per minute and is normally used when calculating the engine torque in a dynamic analysis. But if the requirements below are satisfied, the torque calculations also become valid in Quasi-Static setup equilibrium analyses.

There are in total three requirements that need to be fulfilled in order to support Quasi-Static setup analysis when using an ac_dyno to drive the engine:

1. There can only be one active ac_dyno present in the assembly

2. The ac_dyno element is required to be setup as per below:


• Dyno type = Torque

• Function type = Throttle Demand

3. An output communicator with the matching name “engine_rpm_sse” (engine rpm steady state equilibrium) has to exist in the model, as noted below.

Table 2 Required output communicator for the ac_dyno

The output communicator above has to point to a state variable which calculates the engine speed during the quasi-static equilibrium analysis. The engine speed during this analysis type can be calculated as in the equation below:

engine_speed = total_drive_line_ratio * wheel_speed (1)

Where the wheel_speed is the Quasi-Static speed of the wheels that can be accessed via a VAR1004 call. The total driveline ratio should be calculated as the ratio of engine speed and wheel speed for the given gear position and it includes all ratios in the model such as gear ratio, differential reduction ratio, etc.

If the requirements above are satisfied, the expression of rpm_input state variable in the ac_dyno element gets automatically adjusted for the Quasi-Static setup analysis, as explained below:

Standard expression of rpm_input state variable:

WZ(ac_dyno.i_marker,ac_dyno.j_marker,ac_dyno.j_marker)*60/(2*PI)

Modified expression of rpm_input state variable to suit a Quasi-Static setup analysis:

(IF(MODE-5:0,1,0)+IF(MODE-6:0,1,0))*VARVAL(cos_engine_rpm_sse_adams_id)+(IF(MODE-4:1,1,0)+IF(MODE-6:0,0,1))*WZ(ac_dyno.i_marker,ac_dyno.j_marker,ac_dyno.j_marker)*60/(2*PI)

It is only during mode 5 and 6 (static equilibrium and quasi-static equilibrium) that the value from the engine_rpm_sse output communicator is used. For all other simulation modes, the original expression is kept.

When running an Adams/Car SDI analysis with a Quasi-Static setup, the following message is shown in the Message Window if the setup of the ac_dyno worked properly:

Setting up rpm_input variable in dyno (name of ac_dyno)to support Quasi-Static Straight-Line Setup...Setup of dyno is completed.



From minor role: Receives: Transmitts:

cos_engine_rpm_sse solver_variable any engine_rpm_sse

Adams/Solver variable for (back) calculated engine speed, in revolutions per minute, in the Quasi-Static (steady state) equilibrium phase


12

If an ac_dyno is not used in the assembly, that is, you have modeled your own engine torque implementation, you are still able to use the Quasi-Static setup capability if the following conventions are applied:

1. The engine torque has to be dependent on throttle demand and engine speed. Throttle demand value of 100 should produce maximum engine torque for the specific engine speed.

2. Engine speed expression used in the engine torque calculation needs to be setup in a way that it is still valid in the Quasi-Static setup analysis. The user can use the modified rpm_input state variable expression shown previously as an example. A recommendation is also to use the wheel speeds that are calculated in the way that is done in the shared Adams/Driveline brake system template.

Lastly, it is required that the different powertrain/driveline components properly inherit the calculated Quasi-Static wheel speeds in the initial velocity analysis. This can be accomplished by correctly setting up the initial condition motions. More information can be found in the section “Setting up Initial Condition Motions Activity Analyses” and in section “Setting up Initial-Velocity Analyses.”

Implementation in shared Adams/Driveline SDI vehicle modelIn the Adams/Driveline shared database, the full vehicle assembly JEEP_RWD_SDI.asy is prepared for Adams/Car SDI analysis. The used engine, driveline, gearbox and brake subsystems and templates in that assembly are listed below:

Table 3 Systems in JEEP_WRD_SDI.asy assembly which are involved in the Powertrain/Driveline SDI testrig and Quasi-Static setup communication.

In the Figure 1 an overview of these systems in the assembly is shown. The powertrain/driveline related communication from and to the full vehicle SDI testrig and the internal communication used for the Quasi-Static setup is presented as well. The green “In” arrows shows communicators to a certain subsystem while the blue “Out” arrows lists the information sent from the subsystem.

System Subsystem file: Template file:

Brake system JEEP_brake_system.sub _brake_4Wdisk_adriveline.tpl

Driveline RWD_driveline.sub _RWD_driveline.tpl

Gearbox gearbox_longitudinal.sub _gearbox_longitudinal.tpl

Engine engine_02.sub _engine.tpl


Figure 1 Overview of powertrain/driveline in assembly JEEP_RWD_SDI.asy

Most of the SDI testrig input communicators listed in table 1 are matched in this configuration and the required output communicator “engine_rpm_sse” for the Quasi-Static setup is here located in the engine system. The total_driveline_ratio in equation [2] is here divided into two parameters, gear_ratio and diff_ratio, and can be expressed as below:

total_driveline_ratio = gear_ratio [gear position] * diff_ratio (2)

Next, the powertrain/driveline related communication between the different systems and the parameters such as those above are described in more detail.

Brake system

Starting from the brake system, calls are made to the VAR1004 subroutine that calculates the wheel speeds values during the Quasi-Static setup equilibrium phase. These speed values are then published to other subsystem via the output communicators listed below:


14

• left_front_wheel_omega

• right_front_wheel_omega

• left_rear_wheel_omega

• right_rear_wheel_omega

The inputs to the brake system are mainly brake_demand (received from the SDI testrig) and the tire forces (from the wheel templates). The id’s of the tire forces are passed as parameters in the VAR1004 calls, see Table 6.

Figure 2 Brake template: _brake_system4W_disk_acdriveline.tpl

This template originates from the shared Adams/Car template _brake_system_4Wdisk.tpl. The only difference is that the Adams/Driveline version publishes the wheel speeds.

More complete brake system information about entities related to SDI testrig and Quasi-Static setup are shown in the tables below:


Table 4 Input communicators in brake system which are related to SDI testrig and Quasi-Static setup

Table 5 Output communicators in brake system which are related to SDI testrig and Quasi-Static setup

Communicators:

The input communicator: Belongs to class: Minor role: Matching name:

cis_brake_demand solver_variable any brake_demand

cil_rear_tire_force force rear tire_force

cil_front_tire_force force front tire_force

The output communicator:

Belongs to class:

Minor role: Matching name: Points to entity:

cos_left_rear_wheel_omega solver_variable

any left_rear_wheel_omega left_rear_wheel_omega

cos_right_rear_wheel_omega

solver_variable

any right_rear_wheel_omega right_rear_wheel_omega

cos_left_front_wheel_omega

solver_variable

any left_front_wheel_omega left_front_wheel_omega

cos_right_front_wheel_omega

solver_variable

any right_front_wheel_omega right_front_wheel_omega


16

Table 6 States variables in brake system which are related to SDI testrig and Quasi-Static setup

Driveline

This rear-wheel drive model uses the rear wheel speeds from the brake system to calculate the transmission output speed to be used in the Quasi-Static setup analysis phase, as per the equation below:

State variables:

The state variable:Subroutine parameter: Parameter value:

left_front_wheel_omega par1

par2

par3

par4

par5

1004

(mtl_front_rotor_to_wheel.ptl_actuator_i_1.adams_id)

(mtl_front_suspension_upright.ptl_actuator_j_1.adams_id)

(mtl_front_suspension_upright.ptl_actuator_j_1.adams_id)

(cil_front_tire_force_adams_id)

right_front_wheel_omega par1

par2

par3

par4

par5

1004

(mtr_front_rotor_to_wheel.ptr_actuator_i_1.adams_id)

(mtr_front_suspension_upright.ptr_actuator_j_1.adams_id)

(mtr_front_suspension_upright.ptr_actuator_j_1.adams_id)

(cir_front_tire_force_adams_id)

left_rear_wheel_omega par1

par2

par3

par4

par5

1004

(mtl_rear_rotor_to_wheel.ptl_actuator_i_2.adams_id)

(mtl_rear_suspension_upright.ptl_actuator_j_2.adams_id)

(mtl_rear_suspension_upright.ptl_actuator_j_2.adams_id)

(cil_rear_tire_force_adams_id)

right_rear_wheel_omega par1

par2

par3

par4

par5

1004

(mtr_rear_rotor_to_wheel.ptr_actuator_i_2.adams_id)

(mtr_rear_suspension_upright.ptr_actuator_j_2.adams_id)

(mtr_rear_suspension_upright.ptr_actuator_j_2.adams_id)

(cir_rear_tire_force_adams_id)


transmission_output_omega_sse = (left_rear_wheel_omega+right_rear_wheel_omega)/2*diff_ratio (3)

The transmission output shaft speed is then communicated to other subsystems (used in the engine system in this case). Another output from this system is the diff_ratio which is used by SDI testrig. The diff_ratio parameter value is taken from the reduction gear ratio set in the differential gear arrangement; see Figure 3.

Figure 3 Driveline template: _RWD_driveline.tpl

Note that the transmission output speed (that is, the speed of the input propeller shaft) in equation [3] is not used in any dynamic analysis, where the speed is instead determined by dynamic torque from the gearbox, resistance torque from the differential gear parts, inertia and compliance effects of the propeller shaft, different lash effects, and so on.

More complete driveline information about entities related to SDI testrig and Quasi-Static setup are shown in the tables below:


18

Table 7 Input communicators in driveline system which are related to SDI testrig and Quasi-Static setup

Table 8 Output communicators in driveline system which are related to SDI testrig and Quasi-Static setup

Table 9 State variables in driveline system which are related to SDI testrig and Quasi-Static setup

Table 10 Reduction Gears in the driveline system which are related to SDI testrig and Quasi-Static setup

Gearbox

The gearbox model uses the transmission_demand and clutch_demand from the SDI testrig and publishes to the testrig the gear ratios for all gear positions (transmission_spline), highest gear position number (max_gears) and a scalar value between 0 and 1 which represent a transmission efficiency value. This value is used in (Driving Machine) SmartDriver events. The gearbox input shaft speed (transmission_input_omega) is published to the SDI testrig as well.

Communicators:

The input communicator:

Belongs to class:

Minor role: Matching name:

cis_left_rear_wheel_omega solver_variable any left_rear_wheel_omega

cis_right_rear_wheel_omega solver_variable any right_rear_wheel_omega


Belongs to class:


cos_diff_ratio parameter_real inherit diff_ratio grsred_pinion_drive_to_ring.reduction_ratio

cos_transmission_output_omega_sse

solver_variable inherit transmission_output_omega_sse

VAR_transmission_output_omega_sse

State variables:

The state variable: Function:

VAR_transmission_output_omega_sse

(VARVAL(cis_left_rear_wheel_omega_adams_id)+ VARVAL(cis_right_rear_wheel_omega_adams_id))/2*grsred_pinion_drive_to_ring.reduction_ratio

Reduction gears:

The reduction gear: Joint1: Joint2: Default ratio:

grsred_pinion_drive_to_ring josrev_diff_input josrev_diff_case_body 2.6


Figure 4 Gearbox template: _gearbox_longitudinal.tpl

Since this gearbox can not switch gears during the simulation, the transmission_demand information is only used to calculate the gear ratio value (gear_ratio) for the initial gear position; see expression in Table 15. This value is used in the Quasi-Static setup analysis by the engine subsystem.

More complete gearbox information about entities related to SDI testrig and Quasi-Static setup are shown in the tables below:

Table 11 Input communicators in gearbox system which are related to SDI testrig and Quasi-Static setup

Communicators:

The input communicator:

Belongs to class:

Minor role: Matching name:

cis_clutch_demand_1 solver_variable inherent clutch_demand

cis_clutch_demand_2 solver_variable inherent clutch_demand

cis_transmission_demand solver_variable inherit transmission_demand


20

Table 12 Input communicators in gearbox system which are related to SDI testrig and Quasi-Static setup

Table 13 State variables in gearbox system which are related to SDI testrig and Quasi-Static setup

Table 14 Splines in gearbox system which are related to SDI testrig and Quasi-Static setup


Belongs to class:


cos_max_gears parameter_integer

inherit max_gears pvs_max_gears

cos_transmission_efficiency parameter_real inherit transmission_efficiency pvs_transmission_efficiency

cos_transmission_spline spline inherit transmission_spline gear_ratio_spline

cos_transmission_input_omega

solver_variable inherit transmission_input_omega

VAR_transmission_input_omega

cos_gear_ratio parameter_real inherit gear_ratio gear_ratio

State variables:


VAR_transmission_input_omega WZ(ges_input_shaft.jxs_joint_i_9,mts_body.jxs_joint_j_9, mts_body.jxs_joint_j_9)

Splines:

The spline: Spline values:

gear_ratio_spline -3.0 (dummy value)

0.0

(ues_gear1.ratio)

(ues_gear2.ratio)

(ues_gear3.ratio)

(ues_gear4.ratio)

(ues_gear5.ratio)


Table 15 Parameter and variables in gearbox system which are related to SDI testrig and Quasi-Static setup

Engine

The engine template has in this case the largest portion of the powertrain/driveline related communication with the SDI testrig. The input from the SDI testrig to the engine is the throttle demand (throttle_ demand) while it publishes information different dynamic engine speed and engine torque quantities, as in Figure 5 and Table 16 below. In the Quasi-Static setup analysis, the engine speed is calculated as below:

engine_rpm_sse = gear_ratio * transmission_output_omega_sse (4)

where the gear_ratio parameter value is received from the gearbox subsystem and the Quasi-Static speed of the transmission output shaft (transmission_output_omega_sse) comes from the driveline subsystem.

Parameters / variables:

The parameter/variable name: Type: Units: Default value / parameterisation:

pvs_max_gears integer 5

pvs_transmission_efficiency real no_units 1.0

gear_ratio real VALAT(gear_ratio_spline.xs, gear_ratio_spline.ys, cis_transmission_demand.object_value.initial_condition)


22

Figure 5 Engine template: _engine.tpl

More complete engine information about entities related to SDI testrig and Quasi-Static setup are shown in the tables below:

Table 16 Input communicators in engine system which are related to SDI testrig and Quasi-Static setup

Communicators:

The input communicator:Belongs to

class:Minor role: Matching name:

cis_throttle_demand solver_variable any throttle_demand

cis_gear_ratio parameter_real inherit gear_ratio

cis_transmission_output_omega_sse

solver_variable any transmission_output_omega_sse


Table 17 Output communicators in engine system which are related to SDI testrig and Quasi-Static setup

Table 18 Ac dyno in the engine system which is related to SDI testrig and Quasi-Static setup

Table 19 State variables in engine system which are related to SDI testrig and Quasi-Static setup

The output communicator:Belongs to

class:Minor role: Matching name: Points to entity:

cos_engine_map spline inherit engine_map ues_engine_torque.gss_spline

cos_engine_rpm solver_variable inherit engine_rpm VAR_ENGINE_RPM

cos_engine_speed solver_variable inherit engine_speed VAR_ENGINE_OMEGA

cos_default_downshift_rpm parameter_real inherit min_engine_speed pvs_engine_idle_speed

cos_engine_idle_rpm parameter_real inherit engine_idle_rpm pvs_engine_idle_speed

cos_default_upshift_rpm parameter_real inherit max_engine_speed pvs_engine_rev_limit

cos_engine_max_rpm parameter_real inherit engine_revlimit_rpm pvs_engine_rev_limit

cos_max_engine_braking_torque

solver_variable inherit engine_maximum_braking_torque

VAR_max_braking_torque

cos_max_engine_driving_torque

solver_variable inherit engine_maximum_driving_torque

VAR_max_driving_torque

cos_engine_rpm_sse solver_variable inherit engine_rpm_sse VAR_ENGINE_RPM_SSE

Dynos:

The Dynos: I Part: J Part:

ues_engine_torque ges_crankshaft ges_engine_block

State variables:


ues_engine_torque.rpm_input WZ(ues_engine_torque.i_marker,ues_engine_torque.j_marker,ues_engine_torque.j_marker)

*60/(2*PI)

VAR_ENGINE_RPM ABS(wz(ges_crankshaft.jxs_joint_i_8,ges_engine_block.jxs_joint_j_8, ges_engine_block.jxs_joint_j_8)*60/(2*PI))

VAR_ENGINE_OMEGA VARVAL(VAR_ENGINE_RPM)*PI/30


24

Table 20 Splines in engine system which are related to SDI testrig and Quasi-Static setup

Table 21 Parameters in engine system which are related to SDI testrig and Quasi-Static setup

VAR_ENGINE_RPM_SSE VARVAL(cis_transmission_output_omega_sse_adams_id)*cis_gear_ratio*30/PI

VAR_max_braking_torque AKISPL(MAX(0,VARVAL(ues_engine_torque.rpm_input)),0,ues_engine_torque.gss_spline)

VAR_max_driving_torque AKISPL(MAX(0,VARVAL(ues_engine_torque.rpm_input)),1,ues_engine_torque.gss_spline)

State variables:


Splines:

The spline: Spline values:

ues_engine_torque.gss_spline 3D dimensional engine map spline:

Input parameter 1: Throttle (0->100)

Input parameter2: engine speed (rpm)

Output: engine torque

Parameters:

The parameter: Type: Units: Default value:

pvs_engine_idle_speed real no_units 1000.0

pvs_engine_rev_limit real no_units 6000.0

25Running AnalysesSetting up Impulse-Torque Analyses

Setting up Impulse-Torque AnalysesAn impulse-torque Analysis is a specific Adams/Driveline full-vehicle analysis.

See a plot of the Torque Function During Analysis - Impulse.

To set up an impulse-torque analysis:

1. From the Simulate menu, point to Full-Vehicle Analysis, point to Driveline Tests, and then select Impulse-Torque.

2. Press F1 and then follow the instructions in the dialog box help for Impulse-Torque Analysis.

3. Select OK.

Adams/DrivelineSetting up Ramp-Torque Analyses

26

Setting up Ramp-Torque AnalysesA ramp-torque Analysis is an Adams/Driveline full-vehicle analysis.

See a plot of the Torque Function During Analysis - Ramp.

To set up a ramp-torque analysis:

1. From the Simulate menu, point to Full-Vehicle Analysis, point to Driveline Tests, and then select Ramp-Torque.

2. Press F1 and then follow the instructions in the dialog box help for Ramp-Torque Analysis.

3. Select OK.

27Running AnalysesSetting up Rock-Cycle Analyses

Setting up Rock-Cycle AnalysesA rock-cycle Analysis is an Adams/Driveline full-vehicle analysis.

During this analysis, Adams/Driveline submits the vehicle alternatively to a positive and a negative engine torque simulating a 1st gear - reverse gear engagement, as shown in the figure Effect on Torque. This test modifies only the direction of the engine torque. It does not shift gears.

To set up a rock-torque analysis:

1. From the Simulate menu, point to Full-Vehicle Analysis, point to Driveline Tests, and then select Rock-Cycle.

2. Press F1 and then follow the instructions in the dialog box help for Rock-Cycle Analysis.

3. Select OK.

Adams/DrivelineSetting up RPM Sweep Analyses

28

Setting up RPM Sweep AnalysesAn RPM-sweep Analysis is an Adams/Driveline full-vehicle analysis.

Adams/Driveline sets up the initial velocity according to the RPM values you specify. A motion drives the simulation and applies the RPM-sweep law to the driveline.

To set up an RPM-sweep analysis:

1. From the Simulate menu, point to Full-Vehicle Analysis, point to Driveline Tests, and then select RPM Sweep.

2. Press F1 and then follow the instructions in the dialog box help for RPM-Sweep Analysis.

3. Select OK.

29Running AnalysesSetting up Step-Torque Analyses

Setting up Step-Torque AnalysesA step-torque Analysis is an Adams/Driveline full-vehicle analysis.

See a plot of the Torque Function During Analysis - Step

To set up a step-torque analysis:

1. From the Simulate menu, point to Full-Vehicle Analysis, point to Driveline Tests, and then select Step-Torque.

2. Press F1 and then follow the instructions in the dialog box help for Step-Torque Analysis.

3. Select OK.

Adams/DrivelineSetting up Throttle Tip In - Tip Out Analyses

30

Setting up Throttle Tip In - Tip Out AnalysesA throttle tip in - tip out Analysis is an Adams/Driveline full-vehicle analysis.

Adams/Driveline sets the throttle demand expression based on the values you specified for driving and coasting, and determines the input torque applied to the crankshaft according to the throttle position and crankshaft RPM as inputs for the engine property file.

To set up a throttle tip in - tip out analysis:

1. From the Simulate menu, point to Full-Vehicle Analysis, point to Driveline Tests, and then select Tip In - Tip Out.

2. Press F1 and then follow the instructions in the dialog box help for Tip In - Tip Out Analysis - Throttle.

3. Select OK.

31Running AnalysesSetting up Torque-Loadcase Analyses

Setting up Torque-Loadcase AnalysesA torque-loadcase Analysis is an Adams/Driveline full-vehicle analysis.

Adams/Driveline sets the input torque according to the torque loadcase file you select. When you use a torque loadcase file, you can store an experimental torque time history in an ASCII file and then deliver that to the engine for a dynamic simulation.

See an Example Torque-Loadcase File.

To set up a torque-loadcase analysis:

1. From the Simulate menu, point to Full-Vehicle Analysis, point to Driveline Tests, and then select Tip In - Tip Out.

2. Press F1 and then follow the instructions in the dialog box help for Torque-Loadcase Analysis.

3. Select OK.

Adams/DrivelineSetting up Torque Tip In - Tip Out Analyses

32

Setting up Torque Tip In - Tip Out AnalysesA torque tip in - tip out Analysis is an Adams/Driveline full-vehicle analysis.

See a plot of Torque Function During Analysis.

To set up a torque tip in - tip out analysis:

1. From the Simulate menu, point to Full-Vehicle Analysis, point to Driveline Tests, and then select Torque Tip In - Tip Out.

2. Press F1 and then follow the instructions in the dialog box help for Tip In - Tip Out Analysis - Torque.

3. Select OK.

33Running AnalysesControlling Analysis Output Files

Controlling Analysis Output FilesYour template-based product lets you control the type and content of files an analysis outputs. You can specify whether an analysis outputs a graphics file or results file. Graphics files contain time-dependent data describing the position and orientation of each part in the model. Results files contain a basic set of state variable information that Adams/Solver calculates during a simulation.

Your template-based product automatically reads the files that an analysis outputs.

If any subsystems within the assembly being analyzed contain flexible bodies, your template-based product automatically outputs a results file, regardless of the specifications you made.

To specify analysis output files:

1. From the Settings menu, point to Solver, and then select Output Files.

The Output Files dialog box appears.

2. Select the types of files you want to output.

3. Select OK.

Adams/DrivelineControlling Analysis Output Files

34

Examples

Adams/DrivelineExamples

2

Examples Getting Started Using Adams/Driveline

Example Files:

• Example Bearing Property File

• Example Clutch-Force Property File

• Example Complex-Spring Property File

• Engine Map Property File

• Example Hypoid Gear-Forces Property File

• Example Ride-Wheel Property File

• Example Torque-Converter Property File

• Example Torque-Loadcase File

• Example Viscous-Coupling Property File

../getting_started_driveline/master.htm

1Dialog Box - F1 Help

Dialog Box - F1 Help

Adams/DrivelineBacklash

2

Backlash

(Template Builder) Driveline Components -> Translational/Rotational Backlash -> New/Modify Comprehensive Help

Defines Backlash Components.

The dialog box has two modes: create and modify.

Adams/Driveline models the lash with a force component that exerts a force according to the values you specify for backlash, contact stiffness, and damping. When the angular displacement of the two parts is less then the specified backlash, the force is zero. When the angular displacement is greater than zero, the force is proportionate to the stiffness and damping value.

For the option: Do the following:

Tips on Entering Object Names in Text Boxes.

Backlash Name If creating a backlash, enter a string to define its name.

If modifying a backlash, enter the database name of an existing backlash.

I Part Enter the name of the I part on which the backlash will act.

J Part Enter the name of the J part on which the backlash will act.

Construction Frame Enter the name of an existing construction frame. If the backlash is rotational, it will be used to define the z-axis along which the backlash torque will act, if it is translational it will define the axis of the translational force.

Backlash Enter a real number that defines the angular (for rotational) or linear (for translational) backlash in the units system specified in the pull-down menu on the right side of the text box.

Contact Stiffness Enter a real number that defines the contact stiffness. Once the maximum allowed backlash is reached, Adams/Driveline uses this parameter to model the contact force between the two parts.

Contact Damping Enter a real number that defines the contact damping. Once the maximum backlash is reached, Adams/Driveline uses this parameter to model the contact force between the two parts.

Sharpness Factor Enter a real number that defines the Sharpness Factor. Once the maximum allowed backlash is reached, Adams/Driveline uses this value to model the contact force between the two parts. For more information about sharpness factor see Backlash Components section.

3Dialog Box - F1 HelpBacklash

Lock Select it if you want to deactivate your backlash element by superimposing a rotational/translational motion.

Select to display the Modify Entity Comments dialog box, where you can add multi-line comments to any entity to describe its purpose and function.

Learn about Recording Comments.


Adams/DrivelineBearing

4

Bearing

(Template Builder) Driveline Components -> Bearing -> New/Modify Comprehensive Help

Defines Bearings.




Bearing Name If creating a bearing, enter a string to define its name.

If modifying a bearing, enter the database name of an existing bearing.

I Part Enter the name of the I part on which the bearing force will act.

J Part Enter the name of the J part on which the bearing force will act.

Type Enter the type of bearing:

• left/right - You can define either the left or right bearing in the dialog box, with Adams/Driveline creating the corresponding opposite bearing by default.

• single - Adams/Driveline creates a non-symmetric bearing.

Bearing Type Enter the type of bearing you want to create.

For more information on the following three parameters, see About Translational Backlash Components.

Contact Stiffness Enter a real number that defines the contact stiffness. Once the maximum allowed backlash is reached, Adams/Driveline uses this parameter to model the contact force between the two parts.

Contact Damping Enter a real number that defines the contact damping. Once the maximum backlash is reached, Adams/Driveline uses this parameter to model the contact force between the two parts.

Sharpness Factor Enter a real number that defines the Sharpness Factor. Once the maximum allowed backlash is reached, Adams/Driveline uses this value to model the contact force between the two parts.

Axial Backlash Enter the real number that defines the maximum backlash allowed in the axial direction. The z-axis of the Coordinate Reference determines the axial direction.

Radial Backlash Enter the real number that defines the maximum backlash allowed in the radial direction. The z-axis of the coordinate reference determines the radial direction.

Diameter Enter the real number that defines the diameter of the bearing. Adams/Driveline uses this number to create a graphic for the bearing and to evaluate drag force.

5Dialog Box - F1 HelpBearing

Property File Specify the property file that contains the force data for the bearing. You can enter a new property file name directly in the text box, or right-click to either search the chosen Adams/Driveline database or browse for the file using the file navigator.

Location Select one of the following:

• Delta Location From Coordinate

• Centered Between Coordinates

• Located Along An Axis

• Located On A Line

• Location Input Communicator

• Located At Flexible Body Node

Orientation Select one of the following:

• Delta Orientation From Coordinate

• Parallel To Axis

• Oriented In Plane

• Orient To Zpoint-Xpoint

• Orient Axis Along Line

• Orient Axis To Point

• User-Defined Values

• Orientation Input Communicator

• Toe/Camber



Select to view property file information. By default, your template-based product displays this information in the Information window, but you can choose to display the information in a text editor.

Learn about:

• Working with the Information Window

• Editing Files Using a Text Editor


Adams/DrivelineBench-Test Analysis

6

Bench-Test Analysis

(Standard Interface) Simulate -> Full-Vehicle Analysis -> Driveline Tests -> Bench Test

Performs a Bench-Test Analysis.


Assembly Select the assembly you want to analyze. The menu lists all open assemblies.

Output Prefix Enter a string that specifies the Analysis Output Name. The string can contain only alphanumeric characters and underscores (_). Adams/Driveline appends the suffix _bench to form the complete analysis name. For example, if you enter test45 as the output prefix, the analysis name becomes test45_bench.

End Time Enter a number greater than zero to specify the duration of the Simulation.

Number of Steps Enter the number of output steps in output files (.req, .gra). It affects the resolution of your animations and plots. Make sure that the number of steps you specify is high enough to display the highest frequency you want to observe.

Mode of Simulation Select interactive, background, or files only.

See Mode of Simulation: Interactive, Mode of Simulation: Background, Mode of Simulation: Files_only.

Road Data File Specify a road data file. Tire subsystems use the information in road data files to calculate the tire/ground interaction forces. If your model uses ride tire subsystems, Adams/Driveline automatically deactivates this text box because tire/ground interaction forces are evaluated in a different way.

For more information about road data files, see the Adams/Tire online help.

../../adams_tire/master.htm

7Dialog Box - F1 HelpBench-Test Analysis

Initial Velocity Enter the initial velocity of the car at the beginning of the simulation. You can enter any number greater than or equal to zero. Adams/Driveline uses this value to run an initial velocity analysis just after the static equilibrium and to set all rotational velocities of the driveline.

Adams/Driveline performs this initial velocity analysis using a CONSUB. You can check the syntax in the .acf File. Adams/Driveline automatically deactivates this text box when there is no body or roller rig subsystem in the selected assembly, because it assumes that without any of these subsystems it doesn't make sense to specify an initial velocity.

In the text box to the right of Initial Velocity, select the most suitable units set for the initial velocity. Before performing the analysis, Adams/Driveline automatically converts the model units to the specified units set.

Gear Position Select the initial gear to be used during the simulation. Adams/Driveline sets the transmission_demand in the test rig to the value you specify.

If the model you want to analyze contains gear-pair elements, then Adams/Driveline engages the correct one to both the input and output shafts with kinematic joints.

Create Analysis Log File Select if you want Adams/Driveline to write information about the assembled model and simulation to a log file.

Adams/Driveline names this log file after the output prefix and an output suffix, depending on the full-vehicle analysis you selected. The log file contains information about the type and success of the analysis, date and user, analysis parameters, and the active subsystem used in the simulation.



Select to display the Modify Testrig Demands dialog box, where you can set any expression for test-rig demands (steering, throttle, brake, clutch, and transmission) to perform any kind of analysis. Using this dialog box you can, for example, set time histories for clutch and transmission demands to perform a gear shift event:

TRANSMISSION DEMAND: STEP(TIME, 1.3, 1, 1.5, 2)IC = 1 CLUTCH DEMAND: STEP(TIME,1.2, 0, 1,3, 1) + STEP(TIME, 1.6, 0.0, 1.7, -1) IC = 0


Adams/DrivelineChain

8

Chain

(Template Builder) Driveline Components -> Chain -> New/Modify Comprehensive Help

Defines a chain.




Chain Name If creating a chain, enter a string to define its name.

If modifying a chain, enter the database name of an existing chain.

Input Sprocket Part Enter the name of the I part on which the chain will act.

Driven Sprocket Part Enter the name of the J part on which the chain will act.

I Coordinate Reference Enter the name of the construction frame that defines the rotation axis of the input sprocket part.

J Coordinate Reference Enter the name of the construction frame that defines the rotation axis of the driven sprocket part.

Torsion Stiffness Enter a real number that defines the torsion stiffness. Adams/Driveline uses this parameter to define both the torsion force and the translational force of the chain.

Torsion Damping Enter a real number that defines the torsion damping. Adams/Driveline uses this parameter to define both the torsion force and the translational force of the chain.

Sprocket Radius Method Select:

• explicit - Explicitly define the sprocket radius.

• geometry based - Evaluate the radius from a gear geometry.

If you select explicit, Adams/Driveline displays the following option:

Input Sprocket Radius Enter a real number that defines the sprocket radius.

If you select geometry based, Adams/Driveline displays the following option:

Input Sprocket Geometry Select a gear geometry and have Adams/Driveline evaluate the radius from that geometry.



9Dialog Box - F1 HelpChurning-Drag Force

Churning-Drag Force

(Template Builder) Driveline Components -> Churning Drag-> New/Modify Comprehensive Help

Defines a churning-drag force.




Churning Drag Name If creating a churning drag, enter a string to define its name.

If modifying a churning drag, enter the database name of an existing churning drag.

I Part Enter the name of the I part on which the churning drag will act.

J Part Enter the name of the J part on which the churning drag will act.

Construction Frame Enter the name of the construction frame that defines the direction around which the churning drag will act.

Constant Enter the real number that defines the constant used in the force formulation.

Viscosity Enter the real number that defines the oil viscosity used in the force formulation.

Gear Diameter Enter the diameter of the gear.

Gear Breadth Enter the real number that defines the gear breadth used in the force formulation.



Adams/DrivelineClutch Assembly

10

Clutch Assembly (Template Builder) Driveline Components -> Complex Components -> Entire Clutch

Creates an entire clutch assembly that includes all the parts and connections shown in the figure Clutch Assembly.


Input Shaft to Gearbox Specify the gearbox input shaft part. Adams/Driveline creates entities such as attachments between the input shaft and the hub of the friction disk. This part must already exist.

Flywheel Part Specify the flywheel part. You can select either a general rigid part or a mount part. Very often the flywheel is modeled in the engine template, while the clutch is modeled in the gearbox template.

Reference Construction Frame

Specify the construction frame used to locate all parts and attachments.

As shown in the figure Clutch Assembly, this construction frame must have the z-axis pointing toward the end of the input shaft and has to be located at the beginning of the gearbox input shaft.

Max Deattaching Force Enter a real number that specifies the maximum force that can be exerted when releasing the clutch. Adams/Driveline uses this value to create an actuator force whose expression is:

Force = - Max Detaching Force * (1-VARVAL(Clutch Demand)) Clutch Demand

Clutch Demand Adams Id (optional)

You can:

• Leave it blank - Adams/Driveline automatically creates a Solver variable single input communicator named Torque_demand.

• Select this communicator from the Database Navigator. This communicator gets the clutch signal (0/1) from the test rig.

Pressure Spring Name Enter the name of the spring element between the flywheel and the pressure plate. See the figure Clutch Assembly.

Preload Specify the preload of the spring element connecting the flywheel to the pressure plate.

Property File Enter the property file for the force versus displacement characteristic of the flywheel pressure-plate spring component.

Pressure Plate Name Enter the string for the pressure plate part. Adams/Driveline creates this part and positions it according to the number of friction disks you want to create. See the figure Clutch Assembly.

Pressure Plate Name: Mass Specify the mass characteristics for the pressure plate part.

11Dialog Box - F1 HelpClutch Assembly

Pressure Plate Name: Inertia

Izz is the inertia around the longitudinal axis of the input shaft. Ixx and Iyy are not important because the parts are only rotating around the z-axis.

Friction Disk Name Enter the string for the friction disk part. Adams/Driveline creates this part and positions it according to the number of friction disks you want to create. See the figure Clutch Assembly.

Friction Disk Name: Number

Specify the number of friction disks you want to create in the clutch assembly.

Friction Disk Name: Radius

Enter a real number that specifies the effective radius of the friction disk. Adams/Driveline uses this number to generate a simple graphic for this part and to evaluate friction forces between friction disks and other parts of the clutch assembly.

Torsion Spring: Stiffness Specify the stiffness. (clear)

Torsion Spring: Damping Specify the damping. (clear)

Torsion Spring: Mass Specify the mass characteristics for each friction disk part.

Torsion Spring: Inertia Izz is the inertia around the longitudinal axis of the input shaft. Ixx and Iyy are not important because the parts are only rotating around the z-axis.

If you selected a number greater than 1 in the Number text box, Adams/Driveline displays the following three options:

Intermediate Plate Name Specify the intermediate plate part. Adams/Driveline creates this part and positions it according to the number of friction disks you want to create. See the figure Clutch Assembly.

Intermediate Plate Name: Mass

Specify the mass characteristics for the intermediate plate part.

Intermediate Plate Name: Inertia

Izz is the inertia around the longitudinal axis of the input shaft.

Clutch Property File Specify the property file for clutch contact force characteristics. For example, <db_name>/clutch_forces.cdb/*.clu.

Clearance Enter a real number that specifies the displacement available before contact forces start to arise.


Adams/DrivelineClutch Assembly

12

Friction Radius Enter a real number that specifies the effective radius of all friction surfaces. Adams/Driveline uses this number to evaluate friction forces between friction disks and other parts of the clutch assembly.

Mu Static, Mu Dynamic, Static Vel, and Dynamic Vel

Enter real numbers that specify the friction characteristics of the clutch assembly. For a rotational velocity equal to Static Vel, the friction coefficient is equal to Mu Static. As soon as the rotational velocity is equal to Dynamic Vel, Adams/Driveline sets the friction coefficient to Mu Dynamic. A small amount of slip is always needed to have friction forces.


13Dialog Box - F1 HelpClutch Connector

Clutch Connector

(Template Builder) Driveline Components -> Clutch Connector -> New/Modify Comprehensive Help

Defines a clutch connector.




Clutch Connector Name If creating a clutch connector, enter a string to define its name.

If modifying a clutch connector, enter the database name of an existing clutch connector.

I Part Enter the database name of a part that defines the action part of the clutch connector.

J Part Enter the database name of a part that defines the reaction part of the clutch connector.

Construction Frame Enter the name of an existing construction frame that defines the z-axis about which the clutch torque will act.

Property File Enter a property file suitable for clutch connectors. You can enter a new property file name directly in the text box, or right-click to either search the chosen Adams/Driveline database or browse for the file using the file navigator.




Learn about:



Adams/DrivelineClutch Force

14

Clutch Force

(Standard Interface) Driveline Components -> Clutch Forces Comprehensive Help

Defines a clutch force.




Clutch Force Name If creating a clutch force, enter a string to define its name.

If modifying a clutch force, enter the database name of an existing clutch force.

Property File Enter a property file suitable for clutch forces. You can enter a new property file name directly in the text box, or right-click to either search the chosen Adams/Driveline database or browse for the file using the file navigator.

Clearance Enter a nonnegative real number to define the clearance between the two friction plates.

Adams/Driveline uses the data from the next four options to create the friction versus relative slip curve. See a plot of a typical Friction Versus Relative Slip.

Static Friction Coefficient Enter a nonnegative real number to define the static friction between the two friction plates.

Dynamic Friction Coefficient Enter a nonnegative real number to define the dynamic friction between the two friction plates.

Static Slip Velocity Enter a nonnegative real number to define the velocity threshold at which the static friction becomes fully active.

Dynamic Slip Velocity Enter a nonnegative real number to define the velocity threshold at which the dynamic friction becomes fully active.

Effective Friction Radius Enter a nonnegative real number that defines the effective radius at which the resulting tangent force is acting so as to calculate the clutch torque correctly.

Symmetric Enabled when you modify component pairs (or brothers):

• yes - Modify properties of both components in a pair.

• no - Only modify properties of the selected component.

When you modify a single component, this option is disabled because a single component is by nature asymmetric.

15Dialog Box - F1 HelpClutch Force




Learn about:




Adams/DrivelineComplex (Torsional) Spring

16

Complex (Torsional) Spring

(Template Builder) Driveline Components -> Complex (Torsional) Spring -> New/Modify Comprehensive Help

Defines a complex spring that includes hysteresis.




Complex Spring Name

If creating a complex spring, enter a string to define its name.

If modifying a complex spring, enter the database name of an existing complex spring.

I Part Enter the database name of a part that defines the action part of the complex spring.

J Part Enter the database name of a part that defines the reaction part of the complex spring.

Construction Frame

Enter the name of an existing construction frame that defines the z-axis about which the complex spring will act.

Property File Enter a property file suitable for clutch forces. You can enter a new property file name directly in the text box, or right-click to either search the chosen Adams/Driveline database or browse for the file using the file navigator.

RPM Solver Variable

Enter the name of an Adams/Solver variable that describes the RPM to be used in the hysteresis computation.

Hysteresis Activity Select if you want hysteresis to be active during analysis:

• yes - Adams/Driveline will use both loading and unloading splines.

• no - Adams/Driveline will use only the first spline in property file for spring-torque computation.




Learn about:



17Dialog Box - F1 HelpConstant-Velocity Joint Assembly

Constant-Velocity Joint Assembly

(Template Builder) Driveline Components -> Complex Components -> CV Joint -> New/Modify Comprehensive Help

Creates an entire Constant-Velocity Joint Assembly. A constant-velocity joint is commonly referred to as a CV joint.



CV Joint Name Enter a string to be used as the prefix for all entities in the CV-joint assembly (general parts, rotational backlash, translational backlash, and joints).

CV Reference Frame Specify the construction frame (or hardpoint) used to locate all parts and attachments. This reference frame represents the physical location of the CV joint.

Shaft Inner Point Specify the hardpoint or construction frame used to locate a point to orient the convel joint.

Shaft Outer Point Specify the hardpoint or construction frame used to locate the second point to orient the convel joint.

I Part Specify the name of the I part of the CV joint.

J Part Specify the name of the J part of the CV joint.

Rotational Backlash Enter the rotational backlash in the CV joint. During Simulations, as long as the angular displacement between the two parts is smaller than the rotational backlash value, the transmitted torque will be zero.

The dialog box creates an Adams/Driveline rotational backlash element using default values for contact stiffness, contact damping, and sharpness factor. Afterwards, you can use the Rotational Backlash Modify dialog box to modify values. You can access the Rotational Backlash Modify dialog box from the Components menu or by right-clicking the rotational backlash element.

Plunge Enter the translational backlash in the CV joint.

The dialog box creates an Adams/Driveline translational backlash element using default values for contact stiffness, contact damping, and sharpness factor. Afterwards, you can access the Translational Backlash Modify dialog box to modify values.

Adams/DrivelineCreate IC Motion

18

Create IC Motion

(Template Builder) Driveline Components -> Advanced -> IC Motions Activity

Creates an initial-conditions (IC) motion in the model. All Adams/Driveline predefined elements already contain IC motion to set up the rotational velocity initial conditions, but if you either create your own elements or connect to parts with a spring damper, for example, you must create an IC motion.

Learn about Setting up Initial Condition Motions Activity Analyses.


IC Motion Name Enter the name of the IC motion.

I Part Select the first part you want to connect with an IC motion.

J Part Select the second part you want to connect with an IC motion.

Coordinate Reference Select a construction frame. The IC motion sets up the rotational velocity of the two parts along the z-axis of the construction frame.

Motion Type Select a type of motion:

• zero velocity - The IC motion rotational velocity will be set to zero during the initial-condition analysis, meaning that the two parts it connects will behave as a kinematic system and have the rame rotational velocity.

• inherit vel from front wheels - The body connected using the IC motion will inherit the rotational velocity from the front wheels: typically used for the front differential case part.

• inherit vel from rear wheels - The body connected using the IC motion will inherit the rotational velocity from the rear wheels: typically used for the front differential case part.

• inherit vel from any wheels - The body connected using the IC motion will inherit the rotational velocity from the front and rear wheels: typically used for the central transfer case part.

19Dialog Box - F1 HelpCreate/Modify Differential Gear

Create/Modify Differential Gear

(Template Builder) Driveline Components -> (Kinematic) Differential Gear -> New/Modify Comprehensive Help

Creates or modifies a differential gear.



Differential Gear Name If creating a differential gear, enter a string to define its name.

If modifying a differential gear, enter the database name of a differential gear.

Input Joint Enter the name of the joint that supplies the input motion.

Output Joint 1 Enter the name of the joint for the output motion. The output joint can be either:

• Symmetrical - Enter either the left or the right joint.

• Single - Define the second joint through the Output Joint 2 text box.

Output Joint 2 Enter the name of the second joint for the output motion. You need this parameter only if Output Joint 1 is not symmetrical.

Reduction Ratio Enter a positive real value for the reduction ratio in the following motion equation:

"input motion" = "reduction_ratio" * ("output motion 1" - "output motion 2")/2

Invert output direction from input direction

Select if you want to invert the motion, which allows the differential gear ratio to always be defined as a positive real value.

Active Select if the differential gear will always be active, or will only be active in the kinematic mode.



Adams/DrivelineDifferential Assembly

20

Differential Assembly (Template Builder) Driveline Components -> Complex Components -> Entire Differential Unit

Creates an entire open differential assembly that includes all the parts and connections shown in the figure provided with Topology of Open Differentials dialog box help.


Differential Center Reference Specify the coordinate reference frame that represents the center of the differential. Adams/Driveline creates the rotational axis of the differential according to the z-axis coordinate reference frame you select.

Differential Name (suffix) Enter a differential name, which Adams/Driveline adds to all Parameter Variables, coordinate reference frames, parts, and constraints belonging to the differential.

By changing the name (suffix), you can create several differentials in one template, such as when creating four-wheel-drive differentials.

Side Gear Radius Enter a positive real value for the radius of the side gears, that is, the gears parallel to the ring gear. Adams/Driveline creates a parameter variable named pvs_side_gear_radius_+ suffix when it creates the differential. Modify this variable to change the side gear radius.

Pinion Gear Radius Enter a positive real value for the radius of the pinion gears. Adams/Driveline creates a parameter variable named pvs_pinion_gear_radius_+ suffix when it creates the differential. Modify this variable to change the pinion gear radius.

Ring Gear Outer Radius Enter a positive real value for the radius of the ring gear. Adams/Driveline creates a parameter variable named pvs_ring_gear_radius_+ suffix when it creates the gear radius.

Ring Gear Inner Radius Enter a positive real value for the inner radius of the ring gear. To modify this radius later, right-click the ring gear geometry, and in the dialog box that appears, modify the Diameter text box.

Ring Gear Offset Enter a real value that specifies the offset of the ring gear from the differential center. The offset value can be positive or negative. A positive value positions the ring gear in the z-axis of the differential center reference frame.

Ring Gear Geometry Select if the geometry of the ring gear should represent a geometry suited for helical or hypoid gears:

• Hypoid - Creates a chamfered gear geometry.

• Helical - Creates a cylindrical geometry.

21Dialog Box - F1 HelpDifferential Assembly

Differential Case: Mass Enter a real value that specifies the mass of the differential housing.

Differential Case: Inertia Enter a real value that specifies the inertia of the differential housing. Izz represents the rotational axis.


Adams/DrivelineDriveline IC Motions Status

22

Driveline IC Motions Status

(Template Builder) Driveline Components -> Advanced -> IC Motions Activity

Indicates which point motions are present in each subsystem and lets you deactivate any point motion. Learn about Setting up Initial Condition Motions Activity Analyses.

To display all the point motions available in a subsystem, select a subsystem from the pull-down menu on the top of the dialog box. To exclude a point motion from the group named lock array, and, therefore, not be considered during the initial velocity analysis, select the check box corresponding to each point motion.


Subsystem Select the subsystem whose point motions you want to deactivate. The dialog box displays all point motions available for that subsystem.

Activate All/Deactivate All Select each point motion you want to deactivate by clearing the corresponding check box, or select Deactivate All to deactivate all point motions for that subsystem.

If a check appears in the box next to a motion, that motion remains active.

23Dialog Box - F1 HelpDropped-Clutch Analysis

Dropped-Clutch Analysis(Standard Interface) Simulate -> Full-Vehicle Analysis -> Driveline Tests -> Dropped-Clutch

Performs a dropped-clutch analysis. You can set the engagement time and the engine rotations per minute (RPM). Adams/Driveline sets the input torque according to the values you specify in this dialog box.

See Setting up Dropped-Clutch Analyses.



Output Prefix Enter a string that specifies the Analysis Output Name. The string can contain only alphanumeric characters and underscores (_). Adams/Driveline appends the suffix _dropped_clutch to form the complete analysis name. For example, if you enter test45 as the output prefix, the analysis name becomes test45_dropped_clutch.









Adams/DrivelineDropped-Clutch Analysis

24






Clutch Actuation Time Enter the time needed to engage the clutch. Adams/Driveline uses this time to set the clutch_demand variable that goes from 1 (disengaged) to 0 (full engagement), in the specified time, using a STEP function.

The following two options are used only in closed-loop mode:

Throttle Actuation Time Enter the time needed to ramp up the throttle. Adams/Driveline uses this time to set the Throttle_Demand variable that goes from 0 to the specified value during the throttle actuation time.

The clutch demand expression will be set to:

STEP(TIME, start_actuation_time, 1, start_actuation_time + clutch_actuation_time, 0)

Throttle Final Value [0-100]

Enter a real number between 0 and 100 that represents the final value of the throttle to be reached during the dropped clutch analysis.

The throttle demand expression will be set to:

STEP(TIME, start_time, 0, start_actuation_time + throttle_actuation_time, throttle_final_value)

Start Actuation Time Enter the time at which the clutch and the throttle engagement is supposed to start. This value makes it possible for you to have the model settle down before performing the dropped-clutch analysis.


25Dialog Box - F1 HelpDropped-Clutch Analysis

Engine Dyno Select an engine dyno element that Adams/Driveline can use to apply the correct engine torque to the model. This depends on your selection of either the Open Loop or the Closed Loop option in the pull-down menu that follows.

Closed Loop Select this option if you want Adams/Driveline to keep a crankshaft part you specify at a specific speed until the clutch is engaged.

If you select Closed Loop, Adams/Driveline displays the following options:

Crankshaft Part Select the crankshaft part you want to use.

Engine Rpm Enter an RPM value.

Open Loop Select this option if you want Adams/Driveline to apply a specific engine torque to the model without any control on the engine RPM value.

If you select Open Loop, Adams/Driveline displays the following option:

Constant Torque/Generic Torque Function

If you select Constant Torque, specify a constant engine torque value that will be applied to the model without any control of the engine RPM value.

If you select Generic Torque Function, specify a generic function for the engine torque. To get help on defining an expression, select the

More tool , which is explained next.

If you select Generic Torque Function, Adams/Driveline displays the following option:

Select to use the Function or Expression Builder to define a function. For information on the Function or Expression Builder, see Function Builder.





Friction Coeff Select to display the Modify Friction Coefficients dialog box. If you have an assembly with rtire models, you can use the Modify Friction Coefficients dialog box to modify the friction characteristics for each tire.

For information about rtire, see Ride Wheels.


../../adams_view_fn/master.htm

Adams/DrivelineExport ADM to Adams/Chassis

26

Export ADM to Adams/Chassis

(Standard Interface) Tools -> Driveline Tools -> Export to Adams/Chassis -> Export ADM to Adams/Chassis

If you are more comfortable working with the Adams dataset (.adm) files or like to build additional components either by hand in .adm or with Adams/View and then export to .adm, use this dialog box to export an .adm file to Adams/Chassis. Otherwise, use the dialog box Export Adams/Driveline Model to Adams/Chassis.


Assembly Name Select the driveline assembly whose .adm file you want to export. By default it displays the active assembly.

File Name Enter a name for the exported Adams/Solver dataset file (.adm).

Starting ID Enter the number with which all Adams dataset commands should begin in the powertrain subsystem. Because Adams/Chassis has predefined IDs, such as part, marker, and joint IDs, you should select the number 50000 or greater to ensure no duplicate IDs.

27Dialog Box - F1 HelpExport Adams/Driveline Model to Adams/Chassis

Export Adams/Driveline Model to Adams/Chassis

(Standard Interface) Tools -> Driveline Tools -> Export to Adams/Chassis -> Export Adams/Driveline Model to Adams/Chassis

When you use this way of exporting data to Adams/Chassis, Adams/Driveline creates the XML subsystem which Adams/Chassis can automatically include in the model when you reference this file as the powertrain. If you would rather export an .adm file, see the dialog box Export ADM to Adams/Chassis.


Assembly Name Select the assembly you want to export. By default it displays the active assembly.

Configuration Select one of the following configurations:

• Front Wheel Drive

• Rear Wheel Drive

• Four Wheel Drive

File Name Enter a name for the XML subsystem file that you will export and include as the powertrain subsystem in Adams/Chassis.

Starting ID Enter the number with which all MD Adams dataset commands should begin in the powertrain subsystem. Because Adams/Chassis has predefined IDs, such as part, marker, and joint IDs, you should select the number 50000 or greater to ensure no duplicate IDs.

If you select Front Wheel Drive, Adams/Driveline displays the following options:

Front Left/Right Halfshaft Select the front left/right halfshaft part in the Adams/Driveline assembly.

Torque Application Part Select the part that delivers the input torque to the driveline assembly.

Front Differential Mounting Bushing

Select all the bushings that mount the front differential to the vehicle.

If you select Rear Wheel Drive, Adams/Driveline displays the following options:

Rear Left/Right Halfshaft Select the rear left/right halfshaft part in the Adams/Driveline assembly.

Propshaft Joint Select the joint that connects the engine/torque application part to the driveline assembly.

Rear Differential Mounting Bushing

Select all the bushings that mount the rear differential to the vehicle.

Adams/DrivelineExport Adams/Driveline Model to Adams/Chassis

28

If you select Four Wheel Drive, Adams/Driveline displays the following options:

Front Left/Right Halfshaft Select the front left/right halfshaft part in the Adams/Driveline assembly.

Rear Left/Right Halfshaft Select the rear left/right halfshaft part in the Adams/Driveline assembly.

Front/Rear Differential Mounting Bushing

Select all the bushings that mount the front/rear differential to the vehicle.

Front/Rear Transfer Case Select the constraint that connects the front/rear transfer case to the vehicle.

Propshaft Joint Select the joint that connects the engine/torque application part to the driveline assembly.


29Dialog Box - F1 HelpFlexible Shaft

Flexible Shaft

(Template Builder) Driveline Components -> Flexible Shaft -> New

Creates a flexible shaft.

In Adams/Driveline, you can create flexible shafts using the standard Adams/Car Nonlinear Beams, but you can also specify the number of beams you want to create, instead of creating as many Hardpoints as the number of beams you want to create.



Flexible Shaft Name Enter a string that defines the name of the flexible shaft.

I Coordinate Reference Select a point that indicates the beginning of the shaft. The I Coordinate Reference can be either a hardpoint or a construction frame.

J Coordinate Reference Select a point that indicates the end of the shaft. The J coordinate reference can be either a hardpoint or a construction frame.

Outer Diameter Specify the outer diameter of the shaft. Adams/Driveline determines the mass and inertia properties of the shaft according to the outer radius, thickness, and material type.

Thickness Specify the thickness of the shaft.

N Beams Enter the number of beams you want to create. If you want to simulate the torsion behavior, then you need one beam. If you want to simulate bending effects, you need more beams.

Damping Ratio Specify the damping ratio applied to the beam components.

Material Type Select the material type of the flexible shaft. Adams/Driveline determines the mass properties according to the current density you specified for the material.

Color Select the color of the shaft graphics.



Adams/DrivelineGear Force

30

Gear Force

(Template Builder) Driveline Components -> Gear Force -> New/Modify Comprehensive Help

Defines a gear force (See Gear Forces).




Gear Force Name If creating a gear force, enter a string to define its name.

If modifying a gear force, enter the database name of an existing gear force.

Type Enter the type of gear force:

• Spur Gear. See Spur Gears.

• Bevel Gear. See Bevel Gears.

Input Gear I Part Enter the name of an existing part that defines the input gear force action part.

Input Gear J Part Enter the name of an existing part that defines the input gear force reaction part.

Output Gear I Part Enter the name of an existing part that defines the output gear force action part.

Output Gear J Part Enter the name of an existing part that defines the output gear force reaction part.

Construction Frame 1 Enter the name of an existing construction frame that defines the z-axis around which the first gear rotates.

Construction Frame 2 Enter the name of an existing construction frame that defines the z-axis around which the second gear rotates.

Pressure Angle Enter a real value that defines the gear pressure angle.

Backlash Enter a real value that defines the gear couple angular backlash.

Contact Stiffness Enter a real value that defines the contact stiffness.

Contact Damping Enter a real value that defines the contact damping.

Sharpness Factor Enter a real value that defines the contact Sharpness Factor.

Method Select the method you want to use to define the gear force ratio:

• explicit

• scaled off frustums

• scaled off gears

If you select explicit, Adams/Driveline displays the following options:

Ratio Enter the gear ratio.

31Dialog Box - F1 HelpGear Force

Radius 1/Radius 2 Enter the two radii values. Adams/Driveline calculates the ratio as input radius/output radius.

If you select scaled off frustums, Adams/Driveline displays the following options:

Frustum 1/Frustum 2 Enter two frustums to define the ratio. Adams/Driveline automatically calculates the ratio using the two frustum radii.

If you select scaled off gears, Adams/Driveline displays the following options:

Gear 1/Gear 2 Enter two gears to define the ratio. Adams/Driveline automatically calculates the ratio using the two gear radii.




Adams/DrivelineGear Pair

32

Gear Pair

(Template Builder) Driveline Components -> Gear Pair -> New/Modify Comprehensive Help

Defines a gear pair. See Gear Pairs.

This dialog box has two modes: create and modify.



Gear Pair Name Enter a string that defines the name of the gear pair.

Input Shaft Enter the name of the input shaft.

Output Shaft Enter the name of the output shaft.

Input Construction Frame Specify the name of the construction frame, located on the input shaft, that defines the direction around which the input gear rotates and the position on the input shaft of the input gear.

Output Construction Frame Specify the name of the construction frame, located on the output shaft, that defines the direction around which the output gear rotates and the position on the output shaft of the output gear.

Gear Number Enter a number that defines the gear number. Do not specify the same number for more than a gear pair. Adams/Driveline uses this parameter to create a function that activates the synchronizer force only when the transmission demand variable is equal to the gear number.

Configuration Select the type of connection for the gear-pair component:

• Input Gear to Shaft - The input gear is permanently engaged to the input shaft and the synchronizer is located on the output shaft.

• Output Gear to Shaft - The output gear is permanently engaged to the output shaft and the synchronizer is located on the input shaft. Note that the permanent engagement is done using a perpendicular primitive joint.

For more information on the following four parameters, see About Rotational Backlash components.

Backlash Enter a real number that defines the rotational backlash allowed in the gear mesh. Adams/Driveline uses this value to model the contact force between the two gear parts.

Adams/Driveline always applies backlash on the output shaft.

Contact Stiffness Enter a real number that defines the contact stiffness. Adams/Driveline uses this value to model the contact force between the two gear parts, once the maximum allowed backlash is reached.

33Dialog Box - F1 HelpGear Pair

Contact Damping Enter a real number that defines the contact damping. Adams/Driveline uses this value to model the contact force between the two gear parts, once the maximum allowed backlash is reached.

Sharpness Factor Enter a real number that defines the Sharpness Factor. Adams/Driveline uses this value to model the contact force between the two gear parts, once the maximum allowed backlash is reached.

Invert output direction frominput direction

Specify if you want the two gear parts to rotate in the same direction or not.

Reduction Ratio Method Select either:

• explicit

• scaled off gears


Ratio Specify the gear ratio as a real number. Adams/Driveline updates the gear graphics accordingly.

Input Gear/Output Gear Enter two gears geometries. Adams/Driveline updates the two gear geometries to be consistent with the ratio value you specified above.


Input Gear/Output Gear Enter the diameter of the two gears to define the gear ratio. Adams/Driveline automatically calculates the ratio using the two gear radii.




Adams/DrivelineGearbox Assembly

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Gearbox Assembly

(Template Builder) Driveline Components -> Complex Components -> Entire Gearbox

Creates an entire gearbox assembly. The figure, Gearbox Assembly shows some of the data you must enter in this dialog box.


Reference Frame Specify a construction frame to locate all parts and attachments.

As shown in the figure Gearbox Assembly, this construction frame must have the z-axis pointing towards the end of the input shaft and must be located at the beginning of the gearbox input shaft.

Gearbox Type Specify if you want the gearbox to have five or six gear meshes.

Number of Output Shafts Specify if you want to create a gearbox with one or two output shafts.

Input Shaft: X, Y, Z Specify the location of the beginning of the input shaft with respect to the reference frame.

Input Shaft: Length Specify the length of the input shaft. The length is considered to be along the z-axis of the reference frame.

Input Shaft: Diameter Specify the diameter of the input shaft. Adams/Driveline uses this parameter to create the geometry associated with the input shaft and to evaluate the mass properties of the input shaft.

Shaft 1: X, Y, Z Specify the location of the beginning of the first output shaft with respect to the reference frame.

Shaft 1: Length Specify the length of the first output shaft. The length is considered to be along the z-axis of the reference frame.

Shaft 1: Diameter Specify the diameter of the first output shaft. Adams/Driveline uses this parameter to create the geometry associated with the first output shaft and to evaluate the mass properties of the first output shaft.

Shaft 2: X, Y, Z Specify the location of the beginning of the second output shaft with respect to the reference frame.

Shaft 2: Length Specify the length of the second output shaft. The length is considered to be along the z-axis of the reference frame.

Shaft 2: Diameter Specify the diameter of the second output shaft. Adams/Driveline uses this parameter to create the geometry associated with the second output shaft and to evaluate the mass properties of the second output shaft.

Gear Ratio Enter a real number that indicates the gear ratio of the nth gear mesh.

Gear Width Enter a real number that indicates the width of the nth gear mesh. Adams/Driveline uses this parameter to create a reasonable graphic for the gear mesh.

35Dialog Box - F1 HelpGearbox Assembly

Gear Offset Specify the real number that indicates the location of the nth gear mesh with respect to the reference frame.

Shaft Attachment Specify if you want Adams/Driveline to synchronize the nth gear mesh on the input or on the output shaft.

If you select Input Gear to Shaft, Adams/Driveline:

• Places the synchronizer on the output shaft.

• Permanently joins the gear to the input shaft.

If you select Output Gear to Shaft, Adams/Driveline:

• Places the synchronizer on the input shaft.

• Permanently joins the gear to the output shaft.


Adams/DrivelineHooke Joint with Angle

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Hooke Joint with Angle

(Template Builder) Driveline Components -> Hooke Joint with Angle -> New/Modify Comprehensive Help

Defines a hooke joint with angle.




Hooke Joint Name If creating a hooke joint with angle, enter a string to define its name.

If modifying a hooke joint with angle, enter the database name of an existing hooke joint with angle.

Type Select one of the following:

• left/right - Define one of the hooke joints with angle, and Adams/Car creates the corresponding opposite one.

• single - Define a nonsymmetric hooke joint with angle.

I Part Enter the database name of a part that defines the I part of the hooke joint.

J Part Enter the database name of a part that defines the J part of the hooke joint.

Coordinate Reference Enter a coordinate reference to define the joint location.

I-Part Axis Enter a coordinate reference that defines the I-part axis.

J-Part Axis Enter a coordinate reference that defines the J-part axis.

Angle Enter a real value that defines the angle of the hooke joint.



37Dialog Box - F1 HelpHypoid Gear Force

Hypoid Gear Force

(Template Builder) Driveline Components -> Hypoid Gear Force -> New/Modify Comprehensive Help

Defines a hypoid gear force. See Hypoid Gear Forces.




Gear Name If creating a hypoid gear force, enter a string to define its name.

If modifying a hypoid gear force, enter the database name of an existing hypoid gear force.

Pinion Gear I Part Enter the name of an existing part that defines the pinion gear force action part.

Pinion Gear J Part Enter the name of an existing part that defines the pinion gear force reaction part.

Ring Gear I Part Enter the name of an existing part that defines the ring gear force action part.

Ring Gear J Part Enter the name of an existing part that defines the ring gear force reaction part.

Pinion Construction Frame Enter the name of an existing construction frame to define the z-axis around which the pinion rotates.

Ring Construction Frame Enter the name of an existing construction frame to define the z-axis around which the ring rotates.

Case Construction Frame Enter the name of an existing construction frame to define the z-axis around which the case rotates.

Property File Enter a property file suitable for hypoid gears. You can enter a new property file name directly in the text box, or right-click to either search the chosen Adams/Driveline database or browse for the file using the file navigator.

Contact Stiffness Enter a real value that defines the hypoid gear contact stiffness.

Contact Damping Enter a real value that defines the hypoid gear contact damping.

Differential Location Select one of the following to define the hypoid gear location:

• Front Axle

• Rear Axle

Adams/DrivelineHypoid Gear Force

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Learn about:




39Dialog Box - F1 HelpImpulse-Torque Analysis

Impulse-Torque Analysis

(Standard Interface) Simulate -> Full-Vehicle Analysis -> Driveline Tests -> Impulse-Torque

Performs an impulse-torque analysis. See Setting up Impulse-Torque Analyses.



Output Prefix Enter a string that specifies the Analysis Output Name. The string can contain only alphanumeric characters and underscores (_). Adams/Driveline appends the suffix _impulse_torque to form the complete analysis name. For example, if you enter test45 as the output prefix, the analysis name becomes test45_impulse_torque.








Adams/DrivelineImpulse-Torque Analysis

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Constant Torque Enter a torque value from which Adams/Driveline will create the impulse. The value represents a constant torque value applied to the full-vehicle Assembly before and after the impulse.

Time to Constant Torque Enter the amount of time necessary to ramp the torque up from zero to the constant torque value you specified. Adams/Driveline uses a STEP function. Adams/Driveline sets the initial time and the initial torque to 0.

Impulse Amplitude Enter the amplitude of the torque impulse. Consider this value as an increment from the constant torque value.

Impulse Start Time Enter the time at which the torque impulse starts to develop.

Cycle Length Enter the duration of the impulse.

• At: time = impulse start time + cycle length/2, torque = constant torque + torque amplitude

• At: time = impulse start time + cycle length, torque = constant torque

Engine Dyno Select the engine dyno you want to use to apply the correct engine torque to the model. During the analysis set-up phase, Adams/Driveline sets the dyno type to torque and the function type to torque demand, so that the maneuver can be submitted correctly.


41Dialog Box - F1 HelpImpulse-Torque Analysis








Adams/DrivelineLimited Slip Differential

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Limited Slip Differential

(Template Builder) Driveline Components -> Limited Slip Differential -> New/Modify Comprehensive Help

Defines a limited slip differential. See Limited Slip Differentials.




Limited Slip Differential Name If creating a limited slip differential, enter a string to define its name.

If modifying a limited slip differential, enter the database name of an existing limited slip differential.

Left Side Gear Part Enter the database name of a part that defines the left side gear part.

Right Side Gear Part Enter the database name of a part that defines the right side gear part.

Differential Case Part Enter the database name of a part that defines the differential side gear part.

Construction Frame 1 Enter a Coordinate Reference for the left side gear part.

Construction Frame 2 Enter a coordinate reference for the right side gear part.

Type Select one of the following:

• Viscous

• Clutch Pack

• Torque Sensing

See Limited Slip Differentials for more information on these types.

If you select Viscous, Adams/Driveline displays the following option:

Property File Enter a property file suitable for limited slip differentials. You can enter a new property file name directly in the text box, or right-click to either search the chosen Adams/Driveline database or browse for the file using the file navigator.

If you select Clutch Pack, Adams/Driveline displays the following options:

Friction Coeff. Specify the friction coefficient of the clutch.

Friction Arm Specify the friction arm of the clutch.

Preload Specify the the clutch normal preload.

Ramp Specify the friction arm of the clutch

Side Gear Radius Specify the ramp of the clutch

43Dialog Box - F1 HelpLimited Slip Differential

Left Joint Specify the left joint, which connects the left gear part to the differential case. Adams/Driveline reads the normal load from the joint reaction forces, and determines the clutch torque.

Right Joint Specify the right joint, which connects the right gear part to the differential case. Adams/Driveline reads the normal load from the joint reaction forces, and determines the clutch torque.

If you select Torque Sensing, Adams/Driveline displays the following options:

Variable Type Select one of the following:

• Solver Variable - A solver variable describes the input torque of the limited slip differential.

• Input Communicator - An input communicator describes the input torque of the limited slip differential.

Input Torque Variable/Communicator

Enter an Adams/Solver variable or an input communicator that describes the input toque of the limited slip differential.

Bias Ratio Enter the limited slip differential bias ratio.

Torque Threshold Enter the limited slip differential torque threshold.

Speed Threshold Enter the limited slip differential speed threshold.

Torsen Type Select:

• Type A/B to represent an even torque split between the differential outputs.

• Type C to represent a center differential with a user-specified Nominal Torque Split. The percentage of torque applied to the first and second gear parts must add up to 100. For example, if user enter 30 for First Ratio, Adams/Driveline will suggest 70 for the Second Ratio.


Learn about Recording Comments. Select to view property file information. By default, your template-

based product displays this information in the Information window, but you can choose to display the information in a text editor.

Learn about:




Adams/DrivelinePlanetary Gear

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Planetary Gear

(Template Builder) Driveline Components -> Planetary Gear -> New/Modify Comprehensive Help

Defines a planetary gear. See Planetary Gears




Planetary Gear Name If creating a planetary gear, enter a string to define its name.

If modifying a planetary gear, enter the database name of an existing planetary gear.

Sun Part Select the sun part to build the planetary gear.

Ring Part Select the ring part to build the planetary gear.

Carrier Part Select the carrier part to build the planetary gear.

Sun Joint Select the joint that constrains the sun part to the powerplant.

Ring Joint Select the joint that constrains the ring part to the powerplant.

Carrier Joint Select the joint that constrains the carrier part to the powerplant.

Construction Frame Enter the name of an existing construction frame.

Property File Enter a property file suitable for planetary gears. You can enter a new property file name directly in the text box, or right-click to either search the chosen Adams/Driveline database or browse for the file using the file navigator.




Learn about:



45Dialog Box - F1 HelpRPM-Sweep Analysis

RPM-Sweep Analysis

(Standard Interface) Simulate -> Full-Vehicle Analysis -> Driveline Tests -> RPM-Sweep

Performs an RPM-sweep analysis. See Setting up RPM Sweep Analyses.

Adams/Driveline sets the input rotational motion defined in a dyno element according to the values you specify in this dialog box.



Output Prefix Enter a string that specifies the Analysis Output Name. The string can contain only alphanumeric characters and underscores (_). Adams/Driveline appends the suffix _rpm_sweep to form the complete analysis name. For example, if you enter test45 as the output prefix, the analysis name becomes test45_rpm_sweep.







RPM Start Enter the initial value of driveline RPM. This is the RPM value of the part to which the dyno you select in the Engine Dyno text box is applied.

RPM End Enter the final value of driveline RPM. This is the RPM value of the part to which the dyno you select in the Engine Dyno text box is applied.

Adams/DrivelineRPM-Sweep Analysis

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Engine Dyno Select an engine dyno you want to use to apply the correct engine rotational velocity to the model. During the analysis set-up phase, Adams/Driveline sets the dyno type to motion * Velocity.

The function assigned to the motion is as follows:

RPM_start*(PI/30)+((RPM_end-RPM_start)/end_time)*(PI/30)*TIME








47Dialog Box - F1 HelpRamp-Torque Analysis

Ramp-Torque Analysis

(Standard Interface) Simulate -> Full-Vehicle Analysis -> Driveline Tests -> Ramp-Torque

Performs a ramp-torque analysis. See Setting up Ramp-Torque Analyses.



Output Prefix Enter a string that specifies the Analysis Output Name. The string can contain only alphanumeric characters and underscores (_). Adams/Driveline appends the suffix _ramp_torque to form the complete analysis name. For example, if you enter test45 as the output prefix, the analysis name becomes test45_ramp_torque.








Adams/DrivelineRamp-Torque Analysis

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Initial Torque Enter an initial torque value, applied at time zero. Adams/Driveline start to ramp up the torque from this value.

Ramp Enter a value that defines the slope of the torque-versus-time curve. It defines how fast the torque changes in the unit of time.

Start Time Enter the time at which the torque starts to ramp up.





49Dialog Box - F1 HelpRamp-Torque Analysis






Adams/DrivelineRavigneaux Gear

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Ravigneaux Gear

(Template Builder) Driveline Components -> Ravigneaux Gear -> New/Modify Comprehensive Help

Defines a ravigneaux gear. See Ravigneaux Gears.




Ravigneaux Name If creating a ravigneaux gear, enter a string to define its name.

If modifying a ravigneaux gear, enter the database name of an existing ravigneaux gear.

Short Pinion Sun Part Select the sun part connected with the short pinion.

Long Pinion Sun Part Select the sun part connected with the long pinion.

Ring Part Select the common ring part.

Carrier Part Select the common carrier part.

Short Pinion Sun Joint Select the joint that constrains the short pinion sun part to the powerplant.

Long Pinion Sun Joint Select the joint that constrains the long pinion sun part to the powerplant.

Ring Joint Select the joint that constrains the ring part to the powerplant.

Carrier Joint Select the joint that constrains the carrier part to the powerplant.


Property File Enter a property file suitable for ravigneaux gears. You can enter a new property file name directly in the text box, or right-click to either search the chosen Adams/Driveline database or browse for the file using the file navigator.




Learn about:



51Dialog Box - F1 HelpReduction Gear

Reduction Gear

(Template Builder) Driveline Components -> Reduction Gear -> New/Modify Comprehensive Help

Defines a reduction gear. See Gears.




Reduction Gear Name If creating a reduction gear, enter a string to define its name.

If modifying a reduction gear, enter the database name of an existing reduction gear.

Input Joint Type Select the desired input joint method:

• Kinematic Joint

• Input Communicator

If you select Kinematic Joint, Adams/Driveline displays the following option:

Input Joint Enter the name of the joint for kinematic gear input.

If you select Input Communicator, Adams/Driveline displays the following option:

Input Joint Communicator Enter the name of the communicator for kinematic gear input.

Input Type of Freedom Select the kinematic gear input joint type of freedom:

• Translational

• Rotational

Output Joint Type Select the desired output joint method:

• Kinematic Joint

• Input Communicator

If you select Kinematic Joint, Adams/Driveline displays the following option:

Output Joint Enter the name of the joint for kinematic gear output.

If you select Input Communicator, Adams/Driveline displays the following option:

Input Joint Communicator Enter the name of the communicator for kinematic gear output.

Output Type of Freedom Select the kinematic gear ouput joint type of freedom:

• Translational

• Rotational

Adams/DrivelineReduction Gear

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Method Select the method you want to use to define the kinematic gear ratio:

• explicit - Explicitely specify the reduction gear ratio (as a number).

• scaled off frustums - Select the input part frustum geometry and the output part frustum geometry (associated to the input and output joints). Adams/Driveline calculates the ratio relative to the size of the frustum.

• scaled off gears - Select the input part gear geometry and the output part gear geometry (associated to the input and output joints). Adams/Driveline calculates the ratio relative to the size of the frustum.


Ratio Enter the kinematic gear ratio.

If you select scaled off frustums, Adams/Driveline displays the following options:

Frustum 1/Frustum 2 Enter two frustums to define the ratio. Adams/Driveline automatically calculates the ratio using the two frustum radii.


Input Gear/Output Gear Enter two gears to define the ratio. Adams/Driveline automatically calculates the ratio using the two gear radii.

Invert output direction from input direction

Select if the output direction is to be inverted with respect to the input direction.

Active Select if you want the reduction gear to be always active or just in kinematic mode.




53Dialog Box - F1 HelpRide Wheel

Ride Wheel

(Template Builder) Driveline Components -> Ride Wheel -> New/Modify Comprehensive Help

Defines a ride wheel. See Ride Wheels.




Wheel Name If creating a ride wheel, enter a string to define its name.

If modifying a ride wheel, enter the database name of an existing ride wheel.

Type Enter the type of ride wheel:

• left/right - You can define either the left or right ride wheel in the dialog box, with Adams/Driveline creating the corresponding opposite wheel by default.

• single - Adams/Driveline creates a non-symmetric ride wheel.

Cm Offset Enter the offset for the center of mass of the ride wheel.

Mass Enter a real number that defines the mass of the ride wheel.

Ixx Iyy Enter a real number that defines the xx and yy inertia moments of the ride wheel.

Izz Enter a real number that defines the zz inertia moment fo the ride wheel.

Wheel Center Offset Enter the real number that defines the offset of the wheel center.

Property File Enter a property file suitable for the ride wheel. You can enter a new property file name directly in the text box, or right-click to either search the chosen Adams/Driveline database or browse for the file using the file navigator.

Location Dependency Select one of the following:

• Delta Location From Coordinate

• Centered Between Coordinates

• Located Along An Axis

• Located On A Line

• Location Input Communicator

Adams/DrivelineRide Wheel

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Orientation Dependency Select one of the following:

• Delta Orientation From Coordinate

• Parallel To Axis

• Oriented In Plane

• Orient Axis Along Line

• Orient Axis To Point

• User-Defined Values

• Orientation Input Communicator

• Toe/Camber




Learn about:




55Dialog Box - F1 HelpRoad Friction

Road Friction

(Standard Interface) Simulate -> Full-Vehicle Analysis -> Driveline Tests -> Road Friction

Defines a variable friction coefficient for the tires. The friction expression could have an expression you define or a preformatted expression with three values: initial, intermediate, and final. If you use a preformatted expression, you can select if you want to use the time or the traveled distance as the independent variable for the expression, and the friction will pass from the initial to the intermediate value and from the intermediate to the final value using a STEP5 function.


Wheel Subsystem Select the ride tire subsystem to which you want to assign a variable friction expression.

Define Friction for Select the left or right tire of the subsystem.

Time Based Select the time as the independent variable for the friction coefficient expression.

Distance Based Select the traveled distance as the independent variable for the friction coefficient expression.

Initial Friction Specify the initial value of the friction coefficient.

Intermediate Friction Specify the intermediate value of the friction coefficient.

Final Friction Specify the final value of the friction coefficient.

Define Explicit Function Select to specify your own friction function expression.

If you select Define Explicit Function, Adams/Driveline enables the following option:

Function Expression Specify your own friction function expression.


Set parameters Apply the friction values to the selected subsystem.

If you select Time Based, Adams/Driveline displays the following options:

Time 1 Specify the initial distance. In this phase, the friction will keep the initial value.

Delta 1 Specify the delta value during which the friction will pass from the initial to the intermediate value.

Time 2 Specify the second distance. In this phase, the friction will keep the intermediate value.

Delta 2 Specify the delta value during which the friction will pass from the intermediate to the final value.

If you select Distance Based, Adams/Driveline displays the following options:


Adams/DrivelineRoad Friction

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Distance 1 Specify the initial distance. In this phase, the friction will keep the initial value.

Delta 1 Specify the delta value during which the friction will pass from the initial to the intermediate value.

Distance 2 Specify the second distance. In this phase, the friction will keep the intermediate value.

Delta 2 Specify the delta value during which the friction will pass from the intermediate to the final value.


57Dialog Box - F1 HelpRoad Slope

Road Slope

(Standard Interface) Simulate -> Full-Vehicle Analysis -> Driveline Tests -> Road Slope

Sets the slope of the road. Using this feature, you can easily simulate driveline maneuvers on a nonflat road without using a three-dimensional road property file. A typical maneuver can be a dropped-clutch analysis on a uphill road. In this case, you can simply set the road slope of the hill and then submit a dropped-clutch analysis.


Full-Vehicle Assembly Select the assembly with which you want to perform an uphill maneuver.

Road Slope [%] Define the longitudinal road slope as a percentage.

Side Angle [%] Define the side road angle as a percentage.

Flat Road Select if you want to set back to zero both the road slope and the side angle.

Adams/DrivelineRock-Cycle Analysis

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Rock-Cycle Analysis (Standard Interface) Simulate -> Full-Vehicle Analysis -> Driveline Tests -> Rock-Cycle

Performs a rock-cycle analysis. See Setting up Rock-Cycle Analyses.

Adams/Driveline sets the input torque according to the value you enter in the dialog box. During the rock-cycle analysis, Adams/Driveline submits the vehicle alternatively to a positive and a negative engine torque simulating a first gear-reverse gear engagement.



Output Prefix Enter a string that specifies the Analysis Output Name. The string can contain only alphanumeric characters and underscores (_). Adams/Driveline appends the suffix _rock_cycle to form the complete analysis name. For example, if you enter test45 as the output prefix, the analysis name becomes test45_rock_cycle.







Max Forward Torque Enter a value of engine torque that Adams/Driveline applies when the vehicle is moving forward.

Max Rearward Torque Enter a value of engine torque that Adams/Driveline applies when the vehicle is moving backward.

Distance Enter the distance the vehicle should move. When the vehicle moves, either backward or forward, a distance equal to the distance specified in this text box, the engine torque automatically changes sign. Adams/Driveline performs the transition from Max Forward Torque to Max Rearward Torque in a time equal to the time you specified in the Shift Time textbox.


59Dialog Box - F1 HelpRock-Cycle Analysis

Shift Time Enter the time needed to switch from Max Forward Torque to Max Rearward Torque and back again, when the distance has reached the desired value.









Adams/DrivelineSet Roller Rig Data

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Set Roller Rig Data

(Standard Interface) Adjust -> Set Roller Rig Data

Sets vehicle properties for a roller rig test rig. Using the roller rig test rig, the vehicle data has to be defined so that it can reproduce the dynamic effects of a full-vehicle analysis (for example, vehicle inertia, weights distribution, and aerodynamic effects).


The analysis, through the roller rig, takes into account the vehicle mass, wheelbase, and CG height for the weight changes on the front/rear tires according to your driveline model (front-wheel drive, rear-wheel drive, and so on).

Vehicle Mass [kg] Sets the vehicle mass properties.

Wheelbase [mm] Sets the vehicle wheelbase.

CG Height [mm] Sets the vehicle CG height.

Tire Preload [N] Specifies the nominal tire preload. You must specify the tire preload because you don't have a physical vehicle.

Adams/Driveline uses the data for the next three parameters to model an aero drag effect on the vehicle.

Air Density Sets the air density of the vehicle.

Drag Coefficient Sets the drag coefficient of the vehicle.

Front Reference Surface Set the front reference surface of the vehicle.

61Dialog Box - F1 HelpSet Testrig Demands

Set Testrig Demands

(Standard Interface) Simulate -> Full-Vehicle Analysis -> Driveline Tests -> Testrig Demands

Sets the test-rig demands for a Bench-Test Analysis.


Assembly Select the assembly for which you want to set test-rig demands.

Define Select if you want to define a test-rig demand. For example, if you want to define the throttle demand for your bench-test analysis, select the Define check box that corresponds to Throttle Demand.

<Testrig> Demand Write your own function expression that defines the inputs for your bench-test analysis.


Initial Condition Assign the initial value of the test-rig demand to the value your own function expression should have during the static equilibrium.


Adams/DrivelineStatic Loadcase Analysis

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Static Loadcase Analysis

(Standard Interface) Simulate -> Full-Vehicle Analysis -> Driveline Tests -> Static Loadcase

Performs a Static Loadcase Analysis.



Output Prefix Enter a string that specifies the Analysis Output Name. The string can contain only alphanumeric characters and underscores (_). Adams/Driveline appends the suffix static_loadcase to form the complete analysis name. For example, if you enter test45 as the output prefix, the analysis name becomes test45_static_loadcase.



Static Loadcase File Specify a static loadcase file.



Select to display the Modify Entity Comments dialog box, where you can add multi-line comments to any entity to describe its purpose and function

Learn about Recording Comments..

63Dialog Box - F1 HelpStep-Torque Analysis

Step-Torque Analysis

(Standard Interface) Simulate -> Full-Vehicle Analysis -> Driveline Tests -> Step-Torque

Performs a step-torque analysis. See Setting up Step-Torque Analyses.

Adams/Driveline sets the step torque according to the values you specify in this dialog box.



Output Prefix Enter a string that specifies the Analysis Output Name. The string can contain only alphanumeric characters and underscores (_). Adams/Driveline appends the suffix _step_torque to form the complete analysis name. For example, if you enter test45 as the output prefix, the analysis name becomes test45_step_torque.









Adams/DrivelineStep-Torque Analysis

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Initial Torque Value/Final Torque Value

Enter the initial and final torque values. Adams/Driveline applies a STEP function between these two values to deliver the correct torque at each time step.

Step Start Time Enter the time at which the torque must ramp up from the initial torque value to the final torque value.

Duration of Step Enter the time needed to transition from the initial torque value to the final torque value. At time = step_start_time + duration_of_step, the torque will be fully developed and equal to the final torque value.



65Dialog Box - F1 HelpStep-Torque Analysis








Adams/DrivelineTip In - Tip Out Analysis - Throttle

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Tip In - Tip Out Analysis - Throttle

(Standard Interface) Simulate -> Full-Vehicle Analysis -> Driveline Tests -> Tip In - Tip Out

Performs a throttle tip in - tip out analysis. See Setting up Throttle Tip In - Tip Out Analyses.



Output Prefix Enter a string that specifies the Analysis Output Name. The string can contain only alphanumeric characters and underscores (_). Adams/Driveline appends the suffix _ tin_tou to form the complete analysis name. For example, if you enter test45 as the output prefix, the analysis name becomes test45_tin_tou.








67Dialog Box - F1 HelpTip In - Tip Out Analysis - Throttle






Throttle Initial Value Specify the throttle value at the beginning of the simulation.

Throttle Tin Init Time Specify the time at which the throttle will start the tip-in maneuver: the throttle will increase from the initial value to the tip-in value using a STEP5 expression.

Throttle Tin Delta Time Specify the time range during which the throttle will pass form the initial value to the tip-in value.

Throttle Tin Value Specify the throttle tip-in value.

Throttle Tou Init Time Specify the time at which the throttle will start the tip-out maneuver: the throttle will pass from the tip-in value to the tip-out value using a STEP5 expression.

Throttle Tou Delta Time Specify the time range during which the throttle will pass form the tip-in value to the tip-out value.

Throttle Tou Value Specify the final (tip-out) throttle value.



Adams/DrivelineTip In - Tip Out Analysis - Throttle

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69Dialog Box - F1 HelpTip In - Tip Out Analysis - Torque

Tip In - Tip Out Analysis - Torque

(Standard Interface) Simulate -> Full-Vehicle Analysis -> Driveline Tests -> Tip In - Tip Out

Performs a torque tip in - tip out analysis. See Setting up Torque Tip In - Tip Out Analyses

Adams/Driveline sets the input torque according to the values you specify in this dialog box.



Output Prefix Enter a string that specifies the Analysis Output Name. The string can contain only alphanumeric characters and underscores (_). Adams/Driveline appends the suffix _ tin_tou to form the complete analysis name. For example, if you enter test45 as the output prefix, the analysis name becomes test45_tin_tou.








Adams/DrivelineTip In - Tip Out Analysis - Torque

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Throttle Initial Value Specify the throttle value at the beginning of the simulation.

Throttle Tin Init Time Specify the time at which the throttle will start the tip-in maneuver: the throttle will increase from the initial value to the tip-in value using a STEP5 expression.

Throttle Tin Delta Time Specify the time range during which the throttle will pass form the initial value to the tip-in value.

Throttle Tin Value Specify the throttle tip-in value.

Throttle Tou Init Time Specify the time at which the throttle will start the tip-out maneuver: the throttle will pass from the tip-in value to the tip-out value using a STEP5 expression.

Throttle Tou Delta Time Specify the time range during which the throttle will pass form the tip-in value to the tip-out value.

Throttle Tou Value Specify the final (tip-out) throttle value.



71Dialog Box - F1 HelpTip In - Tip Out Analysis - Torque








Adams/DrivelineTopology of Open Differentials

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Topology of Open Differentials An open differential consists of six general parts:

• Two pinion gears

• Two side gears

• A ring gear

• A differential housing

A revolute joint attaches each gear part, except for the ring gear, to the differential housing. A fixed joint attaches the ring gear to the differential housing.

The differential has three couplers (gear functions). The couplers act between:

• Rear pinion gear - right side gear

• Right side gear - front pinion gear

• Front pinion gear - left side gear

The gear radius specifies the gear ratios.

Open Differential Assembly

73Dialog Box - F1 HelpTorque Converter

Torque Converter

(Template Builder) Driveline Components -> Torque Converter -> New/Modify Comprehensive Help

Defines a torque converter. See Torque Converters.




Torque Converter Name If creating a torque converter, enter a string to define its name.

If modifying a torque converter, enter the database name of an existing torque converter.

Impeller Part Enter the name of the existing part that will act as the impeller part (torque converter input part).

Turbine Part Enter the name of the existing part that will act as the turbine part (torque converter output part).

Case Part Enter the name of the existing part that will act as the case part (torque converter stator).

Construction Frame Enter the name of an existing construction frame that defines the z-axis about which the torque converter will act.

Property File Enter a property file suitable for torque converters. You can enter a new property file name directly in the text box, or right-click to either search the chosen Adams/Driveline database or browse for the file using the file navigator.




Learn about:



Adams/DrivelineTorque-Loadcase Analysis

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Torque-Loadcase Analysis

(Standard Interface) Simulate -> Full-Vehicle Analysis -> Driveline Tests -> Torque-Loadcase

Performs a torque-loadcase analysis. See Setting up Torque-Loadcase Analyses.

Adams/Driveline sets the input torque according to the torque-loadcase file you select. When you use a torque-loadcase file, you can store an experimental torque time history in a ASCII file and then deliver that to the engine for a dynamic Simulation.



Output Prefix Enter a string that specifies the Analysis Output Name. The string can contain only alphanumeric characters and underscores (_). Adams/Driveline appends the suffix _torque_loadcase to form the complete analysis name. For example, if you enter test45 as the output prefix, the analysis name becomes test45_torque_loadcase.








75Dialog Box - F1 HelpTorque-Loadcase Analysis






Torque Loadcase Specify the loadcase file in which Adams/Driveline stores the torque time history. Adams/Driveline saves this file in a directory named torque_loadcases.tbl, under any Adams/Driveline database.


Learn about:




Create Analysis Log File

Select if you want Adams/Driveline to write information about the assembled model and simulation to a log file.



Adams/DrivelineTorque-Loadcase Analysis

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77Dialog Box - F1 HelpTorsion Spring

Torsion Spring

(Template Builder) Driveline Components -> Torsion Spring -> New/Modify Comprehensive Help

Defines a torsion spring. See Torsion Springs.

From this dialog box you can request first attempt values for stiffness and damping, according to cross section and material characteristics. The dialog box has two modes: create and modify.



Torsion Spring Name If creating a torsion spring, enter a string to define its name.

If modifying a torsion spring, enter the database name of an existing torsion spring.

I Part Enter the name of the I part on which the torsion spring will act.

J Part Enter the name of the J part on which the torsion spring will act.

Construction Frame Enter the name of an existing construction frame that defines the z-axis along which the torsion spring torque will act.

Spring Type Select if you want the spring to be linear or nonlinear. When the spring is linear, you can easily calculate the spring stiffness based on the geometric and material parameters.

Damping Enter a real number that defines the torsion spring damping. Adams/Driveline uses this value to model the elastic connection between the I part and the J part.

If you set Spring Type to Linear, Adams/Driveline displays the following option:

Stiffness Enter a real number that defines the torsion spring stiffness. Adams/Driveline uses this value to model the elastic connection between the I part and the J part.

If you set Spring Type to Nonlinear, Adams/Driveline displays the following options:

Property File Specify a torsion spring property file.

Tips on Entering File Names in Text Boxes.

Hysteresis Enter a real number that defines the total hysteresis torque. Adams/Driveline applies half this torque value in either direction.

Adams/DrivelineTorsion Spring

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Select to display the Calculate Material Characteristics dialog box, which you can use to compute the spring torsional stiffness once you specify the material, the section radius, and length.


79Dialog Box - F1 HelpUnbalanced Mass

Unbalanced Mass

(Template Builder) Driveline Components -> Unbalanced Mass -> New/Modify Comprehensive Help

Defines an Unbalanced Mass.




Unbalanced Mass If creating an unbalanced mass, enter a string to define its name.

If modifying an unbalanced mass, enter the database name of an existing unbalanced mass.

Attach to Part Enter the name of an existing part. It defines the part to which the unbalanced mass will be fixed.

Construction Frame Enter the name of an existing construction frame. Unbalanced mass will be positioned at a reference distance from it and will work along its z-axis.

Unbalanced Momentum Enter a real value. This value will be equal to unbalanced mass multiplied by the square of the reference distance.



Adams/DrivelineViscous Coupling

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Viscous Coupling

(Template Builder) Driveline Components -> Viscous Coupling -> New/Modify Comprehensive Help

Defines a Viscous Coupling.




Viscous Coupling Name If creating a viscous coupling, enter a string to define its name.

If modifying a viscous coupling, enter the database name of an existing viscous coupling.

I Part Enter the name of the I part on which the viscous coupling force will act.

J Part Enter the name of the J part on which the viscous coupling force will act.

Construction Frame Enter the name of an existing construction frame that defines the z-axis along which the viscous coupling torque will act.

Property File Specify the property file that contains the data for the viscous coupling.




Learn about:



81Dialog Box - F1 HelpWet Clutch

Wet Clutch

(Template Builder) Driveline Components -> Conceptual Wet Clutch -> New/Modify Comprehensive Help

Defines a wet clutch. See About Wet Clutches.




Wet Clutch Name If creating a wet clutch, enter a string to define its name.

If modifying a wet clutch, enter the database name of an existing wet clutch.

I Part Enter the name of the I part on which the wet clutch force will act.

J Part Enter the name of the J part on which the wet clutch force will apply the reaction torque.


Property File Enter a property file suitable for wet clutches. You can enter a new property file name directly in the text box, or right-click to either search the chosen Adams/Driveline database or browse for the file using the file navigator.




Learn about:



Adams/DrivelineWet Clutch

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Appendix

Adams/DrivelineAdams/Driveline Standard Interface

2

Adams/Driveline Standard Interface

3AppendixAdams/Driveline Template Builder

Adams/Driveline Template Builder

Adams/DrivelineAssembly

4

AssemblyAssemblies are comprised of subsystems that can be grouped together to form suspension assemblies, full-vehicle assemblies, and so on.

You save assemblies in ASCII format.

5AppendixClutch Assembly

Clutch Assembly

Adams/DrivelineConstant-Velocity Joint Assembly

6

Constant-Velocity Joint AssemblyA CV-joint assembly consists of three parts connected with a translational kinematic joint and a constant velocity joint (convel) plus rotational and translational Backlash Components to model the rotational backlash and the plunge of the CV joint.

7AppendixDropped-Clutch Analysis

Dropped-Clutch Analysis A dropped-clutch analysis is a specific Adams/Driveline full-vehicle analysis during which the clutch is suddenly engaged while the engine is rotating at a specified rotations per minute (RPM).

Adams/DrivelineEffect on Torque

8

Effect on Torque

9AppendixFriction Versus Relative Slip

Friction Versus Relative Slip

Adams/DrivelineGearbox Assembly

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Gearbox Assembly

11AppendixSharpness Factor

Sharpness Factor The sharpness factor allows you to define how sharp the transition from the backlash region to the stiff region has to be. The higher the sharpness factor, the sharper the transition. For more information about sharpness factor see Backlash Components section.

Adams/DrivelineStatic Loadcase Analysis

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Static Loadcase Analysis During a static loadcase analysis, Adams/Driveline applies a set of static torques and forces to the model. The Static Loadcase Analysis dialog box performs a quasi-static analysis, and at each time step Adams/Driveline determines the force and torque to be applied to the model according to the content of the Static Loadcase File.

Forces to be applied are expressed in the static loadcase file in g's and they are then simulated by modifying the ACCGRAV vector in the model. This way of expressing the force allows you to easily simulate events such as 1 g acceleration and 0.8 g lateral cornering.

The main goal of this analysis can be the evaluation of forces and displacements on rubber bushings and the calculation of static displacements of each part of the model.

13AppendixStatic Loadcase File

Static Loadcase File A static loadcase file stores information about all the different loadcases you want to apply to the model during the quasi-static maneuver.

The following is an excerpt from a static loadcase file:

$-----------------------------------------------STATIC_LOADS[STATIC_LOADS]{ time x_acc y_acc z_acc torque_x torque_y torque_z}1.0 0.0 0.0 -1.0 0.0 0.0 0.02.0 1.0 0.0 -1.0 0.0 1.0E6 0.0

The first line allows you to simulate the static condition with only the acceleration of gravity. The second line simulates a longitudinal acceleration of 1 g with a torque of 1000 Nm.

You store static loadcase files in the database, in a directory named static_loadcases.tbl

Adams/DrivelineTorque Function During Analysis - Impulse

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Torque Function During Analysis - Impulse

15AppendixTorque Function During Analysis

Torque Function During Analysis

Adams/DrivelineTorque Function During Analysis - Step

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Torque Function During Analysis - Step

17AppendixTorque Function During Analysis - Ramp

Torque Function During Analysis - Ramp

Adams/DrivelineTorque Mode

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Torque Mode In torque mode, you can define the driving torque in three different ways:

• Direct - The driving torque is expressed as a function of the Adams/Solver variable torque_demand. Adams/Driveline defines this variable according to the type of analysis you select.

• Indirect - The driving torque is expressed as a function of engine rotations per minute (rpm) and throttle demand. The output torque is evaluated using an engine-map property file.

• User - You can specify any kind of mathematical function using the Function Builder.

19AppendixWelcome Dialog Box

Welcome Dialog Box

Adams/DrivelineWelcome Dialog Box

20

using adams/driveline - md adams 2010

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