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Computer Science IGCSEPDF 31
142 pagesrevision 46930
PDF 31
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Monitoring system tracks conditions, gathers data, and may
issue warnings.
Control system adjusts operations based on sensor inputs.
Continuous process of using outputs as new inputs is called
afeedback loop.
Sensor type
What it measures
Typical use
Gas
Flow
Level
Acoustic
Humidity
Infra-red
Accelerometer
Sound levels
Liquid levels
Acceleration rate, tilt,
vibration
Levels of water vapour
Detecting motion or a heat
source
Presence of a gas e.g. carbon
monoxide
Rate of gas, liquid or powder
flow
Monitor humidity in greenhouses
Detect gas levels in confined spaces
Monitor gas levels during leak repairs
Detect petrol levels in a car tank
Measure water levels in a tank
Identify drops in water levels from leaks
Detect intruders breaking a security beam
Measure heat radiation to locate people in
emergencies
Detect changes in water flow through pipes
Detect sudden vehicle movement and activate
safety features
Sense device orientation in mobile phones
Detect changes in machinery sound levels
Monitor noise pollution
Identify suspicious sounds in security systems