3 dof helicopter yaw (december 2016)

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