Sensors and actuators
A control loop: a sensor measures, the processor decides, an actuator acts. A thermostat shown step by step.
Transcript
A sensor measures something in the real world, such as temperature, light, pressure or movement, and turns it into an electrical signal.
That signal is analogue, so an analogue to digital converter changes it into a number the processor can use.
The processor compares the reading with the target. If the room is colder than the target, it sends a signal to an actuator, which switches the heater on.
Then the sensor measures again. This loop repeats, and keeps the room close to the target temperature.
Sensor, processor, actuator. A loop that lets a computer control the real world.
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