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Computer Science IGCSEPDF 72
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1. Central Heating System
2. Traffic Light Control System
Closed-Loop Control System (Feedback System)
● Uses feedback to monitor and adjust automatically.
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Control:
● Iftemperature < desired → heater ON
● Iftemperature > desired → heater OFF
Sensors: Vehicle detectors (infrared/magnetic)
Processor: Controls timing and sequence
Sensors: Temperature sensor
Processor: Compares room temperature to target
Actuators: Heater and fan
● More accurate and self-correcting.
Example:
Air conditioner checks room temperature and adjusts cooling automatically.
Flow:
Input → Processor → Output → Feedback (sensor)
6.4 Examples of Automated Systems