mechanical and industrial engineering preliminary design review presentation max perham, andrew...

Mechanical and Industrial Engineering

Preliminary Design Review Presentation

Max Perham, Andrew Dodd, Gregory Kelley, Nathan Fowler

UMass Student Launch Team

2Mechanical and Industrial Engineering

Section Estimated Weight (Lb.) External Length (In)

Overall 12.5 92.0

A) Nosecone/Sample Containment 2 14.0

B) Sample Chute/Main Chute Compartment 1.5 33.0

C) Altimeter Bay 2 4.0

D) Drogue Chute Compartment .5 20.0

E) Altitude Control System 2 3.0

F) Motor Tube/Fin Can 4.5 18.0

Launch Vehicle Summary


A statically stable rocket will have its center of pressure located aft of the center of gravity

Used Rocksim to size the fins to give a stability margin of greater than 1.5 and less than 2.62 or more that was not over

Further Rocksim Simulation shows a successful flight with current configuration and a failed flight with an unstable rocket

Static Stability Margin

Example of stable flight in Rocksim

Example of unstable flight in Rocksim

Current Configuration

Unstable Configuration (Small fins)

3,600 feet

240 feet


Component Material Justification Example Photos

Nosecone Plastic Hollow, easy to modify for sample containment system

Body tubes Magnaframe Phenolic Tubing

High-Strength and low weight, these tubes were suggested by our mentor

Inner Tubes Phenolic tubing Standard for interior tubes

Shock Cords Kevlar Tubes Heat Resistant, stronger than nylon shock cord

Parachutes Nylon TAC-1 Military grade parachutes are extremely tough and effective. Most of the large scale successful launches we have seen use this type of parachute

Fins 1/8th inch Aircraft Plywood with optional fiberglass layer

Plywood is strong and cheap

Material Selection and Justification


Selection: AMW J370 Green Gorilla motor (For now) Justification of Selection

• Performed well in Rocksim simulation, reaching an altitude of 3600 feet• Same size as the more powerful J400 RR and J480 BB motors

Motor selected to overshoot target altitude by 500 ft.(3500 ft.)• Aerotech K1199N/ Aerotech K680R described in the proposal too powerful• AMW motor’s easily swappable to account for inaccurate mass estimations

High adaptability for varying masses • This makes this family of motors ideal for the new rocket team

Assuming J370GG is selected• With an average thrust of 82.2 lbf. we have calculated a T/W of 6.65• With an 8 foot rail we have a Rocksim Simulated rail exit velocity of 50.4 ft/s

Baseline Motor Selection

Motor Option Allowable Mass increase

J370 GG 14%

J400 RR 20%

J480 BB 30%

Green Gorilla

Red Rhino

Blue Baboon


Vehicle Safety Verification and risk mitigation plan dictated in section 6.5 of the PDR. • Safety hazards detailed in the manner shown below

To ensure that our full scale rocket meets all safety requirements we will be applying the same metrics to our subscale models.

Plan for Vehicle Safety Verification and Testing

Hazard Cause Effects Likelihood Severity Mitigation StrategyVehicle is unstable CG is closer than CP to the

aft section of the rocketLaunch Vehicle will turn end over end out of control in the air

1 4 Ensure thorough computer simulation analysis. Verify that CG and CP are separated by at least 2 body diameters.


Identification of Verification Plan• Each subsection and component has a verification

strategy detailed in our PDR. • These individual subsection verification plans,

along with the verification plan for meeting the statement of work requirements, have been collected into a checklist

Testing Plan• Follow all applicable verification strategies during

the construction of our subscale models• Construct test rigs to verify components and

features that the subscale model cannot properly model

Launch Vehicle Verification and Testing


Material: Magnaframe vulcanized fiber and phenolic, 3.9” ID - 4.01” OD

Room for all payloads and electronics Material Selection criteria:1. Lightweight2. Cost effective3. Commercially Available4. Resilient

Airframe


4 Fins are specified Fins extend through the airframe, attached to

airframe and motor tube Joints reinforced with fiberglass fillets

Fins


Material Choice: 1/8 fiberglass reinforced marine grade plywood

1. Ease of material fabrication2. Strength and weight3. High density marine lamination (no voids)4. Easily obtained

Fins


Triple deployment scheme Ignition redundancy for each of the deployment

stages (drogue, sand sample, and main). 3000ft apogee: Drogue 1000ft: Sample 600ft: Main

Recovery System: Summary


Recovery System: Deployment Process


Processor Atmel AVR Risc ProcessorMemory 1024 kbAcceleration Transducer (type, range, resolution)

Analog, -50-50g, 0.1g

Pressure Transducer(type, range, resolution)

Motorola, 20-105 kPa, 0.09 kPa

Analog Inputs 6Digital Inputs 4Igniter Output Ports 4 (2 programmable)Size 1.1" x3.15" printed circuit

boardPower Supply 9V-15V

Recovery Altimeters: AED R-DAS Tiny Barometric Altitude Acceleration Velocity Mach Number Coefficient of Drag Thrust


Axial Accelerometer Range and Frequency

70G, 400Hz

Axial Accelerometer Resolution .09 GsLateral Accelerometer Range and Frequency

35Gs, 200Hz

Lateral Accelerometer Resolution .09 GsDownload Interface USB MiniBarometric Pressure Range 100 KftBarometric Pressure Resolution .00004 atmPyro Outputs 4Additional Recorded Measurements Temperature, Cont. &

Batt voltages, Event Logic

Size 0.8”x 1.8”x0.5”Mass 6.6 gramsPower Source 3.8V-16V

Recovery Altimeters: Featherweight Raven 3

• 4 Programmable outputs for ejection events• Lightweight and compact• Programmable flight simulations for testing• After launch detection, the raven takes periodic measurements of

acceleration, barometric pressure, output voltage and current, and temperature.


Parachute Purpose

TypeMaterial

Diameter [in]

Mass (oz)

Descent Rate [ft/s]

Impact Energy Impact Margin

Drogue (full launch vehicle)

TAC-1 36Mil Spec Nylon (1400lb test)

36 8.1 33.97 N/A (no impact under drogue)

N/A

Main (separated launch vehicle)


72 18.0 16.37 31.942 58.11%

Sample (nosecone)


24 5.4 23.57 28.814 61.58%

Recovery System: Parachute Sizing and Specification


TAC-1 Parachutes from Giant Leap RocketryTAC-1 Parachute Specifications Tear-resistant - All seams are reinforced with nylon webbing. Strong - 1/2" mil spec nylon (1400 lb test) all around the canopy. Lightweight - 1.1 oz silicone-coated low-porosity ripstop nylon. No Tangle Design – Utilizes only four suspension lines with a

1500# test swivel for tangle-free descents. All the seams are strength-reinforced with nylon webbing.

Recovery System: TAC-1 Parachutes


U-bolts, 0.5” Tubular Kevlar Shock Cord, Barrel swivels, Quick link connectors.

Recovery System: Parachute Attachment Scheme


Bulkheads Harness Attachment Hardware Blast Protection

Recovery System: Robustness


Section Charge Size [g] Force Produced [lbf]

Shear Pin Specs

Drogue Bay 1.16 179.19 (3) 4-40 Nylon screws

Sample Bay 0.91 179.19 (3) 4-40 Nylon screws

Main Bay 1.46 179.19 (3) 4-40 Nylon screws

Recovery System: Ejection Charges


Pressure chambers located within the UMass Engineering Department’s Mechanical Testing Lab

Light bulbs will be wired to ejection outputs on altimeters to verify current firings at simulated fight event altitudes.

Testing of electronic interference of the altimeters Validate the effectiveness of altimeter shielding setups

Recovery System: Electronics Testing and Interference


Purpose: Limit the maximum apogee altitude Rational: Score more competition points Implementation: Extendable tabs

Altitude Control System (ACS)


The control tabs will extend beyond the airframe after engine burnout

Sensors will calculate apogee based on current vehicle state, enact control effort to add drag to the vehicle as necessary



Implementation:• Servo motor drives center hub• Tabs extend symmetrically outward• Microcontroller to implement algorithm

Advantages• Flat tabs constant drag coefficient• Symmetric stable drag application• Integration housed in a standard coupler tube



Development of Control Algorithm• Simulink modeling of complex system• Nonlinear drag and variable air density



Standard coupler tube e-bay U-bolt parachute attachment at both ends External “key” altimeter arming switches ABS prototype end caps

Electronics Bay


The sample will be housed in the nosecone Integral part of the AGSE sequence Nosecone has a sliding drawer for the sample

Nosecone Sample Containment


Outer Nosecone 3.9”x17” plastic nosecone• Inexpensive, available, smooth

Internal structures Prototype ABS• Inexpensive, complex shapes possible

Containment system sliding drawer• Small stepper motor runs a screw bolt to draw the

sample drawer in• Obtains power and signals through quick disconnect

cable to AGSE• Holds drawer securely in place without power



The nosecone will be its own subsystem, triggering its own separation from the rocket

Electronics housed in the base of the nose• Raven altimeter (with arming switch)• Tagg GPS Locator

End cap with U-bolt parachute connection



Primary function – • To pick up a sample container in a predefined location • Then move it to another predefined location

Approach – • Robotic arm assembly

(5 DoF)• Pliant rubber coated

grasping pincers• Structure to be highly

robust• Moment support with

stakes, heavy base

AGSE and Payload Design


Power – 7.2 V battery

Logic/Control – VEX

PIC microcontroller

• Motor controllers

Movement – motors,

turntables, sprocket and

chain for delivering high torque further from center of mass

Structure – Steel chassis, aluminum robotic arm structure for minimum moment

Sensors – Potentiometers, accelerometer

Subsytems


Identification of Verification Plan• Each subsystem will be tested separately• Each DoF will be tested separately• These individual subsection verification plans, along with the

verification plan for meeting the statement of work requirements, have been collected into a checklist

Testing Plan• Follow all applicable verification strategies during the

construction of our subscale models• Construct test rigs to verify components and features that the

subscale model cannot properly model

AGSE Verification and Test Plan

mechanical and industrial engineering preliminary design review presentation max perham, andrew...

Documents

rocksim simulation

rocket launch vehicle

justification slide

launch vehicle summary

scale rocket

justification of selection

successful flight

rocksim simulated rail