Control Systems

Description

This course is an introduction to the design and analysis of control systems. A control system is a system that commands another system in way that ensures that the overall system does what we want it to. A simple example is a thermostat controlling a heater to ensure that a room doesn't get too hot or too cold, but much more sophisticated kinds of control systems exist. A good understanding of control systems is useful in the design of electric power systems (generator excitation control, tap-changing transformers, etc.), aircraft (autopilots and flight control), rockets and spacecraft (attitude control), cars (cruise control, engine control, etc.), robots (position and speed control), and in many other application areas.

To control a system so that it does what we want we first need to understand how the system responds to different command inputs. The course begins by looking at how to mathematically model different kinds of systems, and how to analyse and simplify models using tools such as the Laplace Transform. We then introduce feedback control systems, which are systems in which the controller continually checks that the controlled system is doing what it supposed to do and modifies its commands to ensure the desired result occurs, making the controller robust to uncertainties in the system model and disturbances in the environment. We look at several different techniques for understanding and improving the stability and performance of feedback controllers, as well common types of controller designs such as the classic PID controller. Most modern controllers are implemented digitally, so we also look at how the techniques we have already learned can be applied to digital systems, and how to use digital controllers for feedback control of physical systems.

Practical work includes several labs working with simulated control systems, and a small practical project designing and implementing a digital controller for a mobile robot.