Control : Components

A typical computer system which is used for control will need to include :

A computer (or microprocessor).
Some sensors to enable the computer to detect quantities such as temperature or pressure.
Some devices for the computer to turn on and off.
An interface to connect the sensors and devices to the computer.
Some software to read data from the sensors and decide when to turn the devices on and off.

The sensors will be used to measure the physical quantities of interest. This data will be transmitted via the interface to the computer. The software that is running on the computer will use the data to decide which devices to turn on or off. The devices will then be turned on or off through the interface.

Sometimes the computer, software and interfaces can be combined together onto a single circuit board to be used inside a machine such as a washing machine (to control the wash cycle). This type of control system is called an embedded control system. A new car contains many embedded control systems.

GCSE ICT Companion 04 - (C) P Meakin 2004