Control Theory

1. Modeling and Control of Two-linked Inverted Pendulum

Inverted pendulum is highly non-linear and open-loop unstable system. It consists of a vertical pendulum attached at the bottom, referred to as pivot point mounted on a cart. This makes the inverted pendulum inherently unstable and must be actively balanced in order to remain upright by moving the cart horizontally. The control method of the system has wide application such as self-balancing robots and rockets launching and Segways transport. In this project, work will begin with a derivation of the mathematical model of the two-linked inverted pendulum system, in the transfer function and/or state space form. Next, the analysis of the open loop response of these models needs to be carried out for comparison purpose. It follows with several controllers designed such as PIDs, state space controllers (e.g. full state feedback) and artificial intelligence controllers (e.g. fuzzy logic control). The performance of the designed controllers will then be compared and analysed. Implementation will be carried out using MATLAB SIMULINK or using other compatible software. Verification of the designed controllers will be done in the laboratory using the real inverted pendulum system.

2. Modeling and Control of A Two-Dimensional Two Rotor Aero-dynamical System (TRAS)

The Two Rotor Aero-dynamical System (TRAS) is a laboratory set-up designed for control experiments that mimics a certain aspects of helicopter’s behaviour. It exemplifies a high order non-linear system with significant cross-couplings. The TRAS consists of a beam pivoted on its base in such a way that it can rotate freely both in the horizontal and vertical planes. At both ends of the beam there are rotors (i.e. the main and tail rotors) driven by DC motors. The aerodynamic force is controlled by varying the speed of the propeller rotors which results in a change of the corresponding position of the beam. Designing of stabilising controllers for such a system is based on decoupling. In this project, work will begin with a derivation of the mathematical model of the TRAS system, in the transfer function and/or state space form. Next, the analysis of the open loop response of these models needs to be carried out for comparison purpose. It follows with several controllers designed such as PIDs and state space controllers (e.g. full state feedback). The performance of the designed controllers will then be compared and analysed. Implementation will be carried out using MATLAB SIMULINK. Finally, verification of the designed controllers will be done in the laboratory using the real TRAS system.

3. Modeling and Control of An Active Car Suspension System based on Half Car Model

The concept of using an active suspension system for vehicles is to provide the best performance of car controlling. A fully active suspension system aim is to control the suspension over the full bandwidth of the system. It is considered to be the way of increasing load carrying, handling and ride quality. In this project, work will begin with a derivation of the mathematical model of the passive and active car suspension system, in the state space form. Next, the analysis of the open loop response of these models needs to be carried out for comparison purpose. It follows with a suitable and several controllers designed including a State Space Controllers (i.e. full state feedback and optimal controller) and Artificial Intelligence Controllers (fuzzy logic and neural network controller). The performance of these four controllers which applied to the active suspension system will be compared and analyzed. Implementation will be carried out using MATLAB SIMULINK or using other compatible software (such as Scilab).

4. Modeling and Control of a Coupled Drives System

Coupled drives system is one of the important systems for controlling the rotating loads as in the industrial systems or home products. For example, the speed of a conveyor belt in a production line will be controlled by separate motors (i.e. two or more) at different positions along the belt. The outputs of the motors are coupled together by a conveyor belt and must work in harmony to maintain the belt speed and ensure that the belt tension is acceptable. If it is not controlled properly, the system will perform badly or it will become unsafe or unstable. In this project, work will begin with a derivation of the mathematical model of a standard coupled drives system which consists of two motor drives and one jockey arm for tension measurement, in the transfer function and/or state space form. It follows with a suitable and several controllers designed including a State Space Controllers (i.e. full state feedback and optimal controller) and Artificial Intelligence Controllers (fuzzy logic and neural network controller). The performance of these four controllers which applied to the coupled drives system will be compared and analyzed. Implementation will be carried out using MATLAB SIMULINK or using other compatible software (such as Scilab).