Control System Design and Analysis

A system, whose output can be managed, controlled or regulated by varying its input is called Control System. If we look around, we will find many control systems in our surroundings i.e. Refrigerator, Air Conditions, Washing Machines etc.

An automatic speed control system, also called cruise control, works by using the difference, or error, between the actual and desired speeds and knowledge of the car’s response to fuel increases and decreases to calculate via some algorithm an appropriate gas pedal position, so to drive the speed error to zero. This decision process is called a control law and it is implemented in the controller. The car dynamics of interest are captured in the plant. Information about the actual speed is fed back to the controller by sensors, and the control decisions are implemented via a device, the actuator, that changes the position of the gas pedal. The knowledge of the car’s response to fuel increases and decreases is most often captured in a mathematical model.