• A controlled system includes,
- a basic system that does not achieve objectives by normal means - for our purposes a mathematical model a such a system is very important.
- some objective for the operation of the system.
- a controller that is matched to system, and tuned to meet the control objective.
• Objectives for control systems might include,
• The systems below are often directed by control systems.
- Neither of these systems have controls.
- They both have inputs, and outputs.
- The output is not always something exiting the system. eg. the water tank height
- We can treat these systems with ‘black boxes’ with lumped parameters.
• All of the inputs and outputs are expressed as physical quantities (as will be seen later).