3 dof helicopter yaw (december 2016)
TRANSCRIPT
3DOF Helicopter Yaw (December
2016)The 3 DOF Helicopter system is a simplified helicopter model, ideally suited to introduce
intermediate to advanced control concepts and theories relevant to real world applications of flight
dynamics and control in the tandem rotor helicopters, or any device with similar dynamics
1. Hamza Saeed Khan SP14-EPE-0962. Sajid Ali SP14-EPE-0193. Mujtaba Hussain SP14-EPE-0924. Shakir Muhammad SP14-EPE-0425. Abdu-Rauf SP14-EPE-0226. Amir Shahzad SP14-EPE-0037. Arif Hussain SP14-EPE-0448. Amir Iqbal SP14-EPE-001
Group Members
Helicopter: a type of aircraft which derives
both lift and propulsion from one or more sets of horizontally revolving overhead rotors. It is capable of moving vertically and horizontally, the direction of motion being controlled by the pitch of the rotor blades.
Yaw: (of a moving ship or aircraft) twist or oscillate about a vertical axis
What does 3-DOF stand for?>Three Degree Of Freedom.
Introduction
Block Diagram of
Heli.
Position sensor: This sensor will sense position of
the propeller motors. Propeller motor: A propeller is a type of fan that
transmits power by converting rotational motion into thrust (means Thrust is a reaction force), actuated by DC motors
Balance block: It will balance the whole block of 3DOF helicopter.
Slip rings: The slip ring mechanism on the vertical axis allows the body to rotate continuously
Explaining blocks
Degree of freedom: means independent
parameters that define its configuration, motions and dimensions.
We will deals in 3-DOF helicopter. We only deal with Pitch, Yaw, and Roll in
position of the body of Helicopter model.
3-DOF
6-DOF means six degree of freedom. We
examine it to clarify such aspect of 3-DOF case for position of YAW as follow:
6-DOF
Explaining 3-DOF
There are differential equations to describe
the whole dynamics of the system: Travel Axis: As our project is based on Yaw so
also called travel axis of 3-DOF Helicopter. When the roll axis is tilted and overturned, the
horizontal component of G will cause a torque about that the travel axis which results in an acceleration about the travel axis, Assume the body has roll up by an angle p as shown in Figure 3
Mathematical Modeling
Simplified model of
Travel axis
The differential
equation is:
First we will find transfer function after derive
travel axis differential equations above so; In order to achieve a desired travel rate (tc),
we will design a closed loop controller to command a desired roll angle;
Transfer function design
Instantaneously and accurately, from the
above two equations, we can write the closed-loop transfer function;
There are two types of networks i-e Active and
Passive. Active Types: Has the following compensators
PI, PD, and PID. Passive Types: Has the following compensators
i-e Lag compensator, Lead compensator, and Lead-Lag compensator.
Controller Designing
We designed PI for
this system From this diagram we clarify all the controllers
as;
For PI controller we put D (kd=0) equals zero
in above diagram.
Increasing Kp will reduce the steady state
error. After certain limit, increasing Kp will only
increase overshoot. Kp reduces rise time.
Conclusion
The 3 DOF Helicopter can be used: for research in various areas, including
adaptive control, nonlinear control, optimal control, predictive control, fault detection and system identification
Application