Area 12
Control systems
Feedback that keeps a system on target
Control systems measure what a machine is doing, compare it with what it should do and correct it, again and again. This feedback keeps a room at the right temperature or a tank at the right water level.
Who it suits
Learners who enjoy graphs and fine-tuning, and anyone who has wondered how a thermostat keeps a room warm.
What you will learn
- What feedback is: measure, compare, correct
- How sensors and controllers work together
- How a PI or PID controller decides how strongly to react
- Why a system can overshoot or swing, and how to make it steady within the teaching model
Example experiments
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Keep a virtual tank at a target water level by controlling a valve.
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Tune a controller and watch whether the temperature overshoots the target.
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Switch feedback off and on, and compare how the system behaves.
Things you can build
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A thermostat for a greenhouse
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A water-level controller for a tank
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A motor that holds a steady speed
These examples show the kind of work in this area. The published lessons may differ.
What the simulation simplifies
- Systems are simplified teaching models: they show the idea of control, not the exact behaviour of a real machine.
- Real sensors are noisy and slow, and real machines have limits that a model may leave out.
Every simulation simplifies reality. Knowing how it does so is part of learning engineering.
Links to school subjects
Mathematics (graphs and rates), physics, computer science, technology
Connections to other areas
Control systems build on automation, sensors and electrical circuits, and they keep robots, heating and water systems steady.
Good to know
Your body uses feedback too: when you get too warm you sweat to cool down, and when you get cold you shiver to warm up.