The three components of a control system can be described using this simple flowchart:
The control program will contain all the instructions needed for the computer to decide when to turn the actuators on and off. They would normally be planned using a flowchart first then entered into the computer using a programming language.
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| Examples of Real-Life Control Systems |
All these control systems are examples of open-loop systems – they stop after they have made the actuator do something.
| Situation |
Decision to Make |
| Microwave |
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If the ‘start’ button is pressed, heat the food inside for 30 seconds. |
| Door bell |
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If the button is pressed, buzz a bell for five seconds. |
| Lamp |
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If the switched is pressed in, turn the lamp on. If the switch is pressed out, turn the lamp off. |
| Television set |
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Turn the television on or off when the standby button is pressed on the remote control. |
| Screen turtle |
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Move the turtle in the direction of the arrow key that is pressed. |
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