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Computer Science IGCSEPDF 71
142 pagesrevision 46930
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Motor
Pump
Heater
Buzzer
Light / LED
Flow:
Input → Processor → Output
Moves liquids
Produces heat
Produces sound
Produces rotational
movement
Provides illumination
● No feedback used.
● System does not check if the desired result is achieved.
● Simple but less accurate.
Alarms
Indicators
Examples:
● Microwave timer turns off after a set time (not based on food temperature).
● Sprinkler turns on for 5 minutes regardless of soil moisture.
Fans, robot arms
Ovens, incubators
Greenhouses, washing
machines
6.3 The Control Process (Feedback Systems)
Open-Loop Control System