A feedback loop links measurement, comparison and action. The sensor supplies information; the controller uses a rule; the actuator affects the controlled system. Without feedback, an always-on heater ignores the measured result. Our simplified heater cannot actively cool an already warm box, illustrating that control also depends on what the actuator can do.
Engineering and scientific investigation · Discover & try
How can a measurement guide a machine?
Reading level 3 of 5 · IndependentChange
Word help
Sensor
A component that measures a condition.
Actuator
A component that changes a physical process.
Watch · Try · Explain
See how it works
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Invented warm-box dynamics and a simple threshold rule. The actuator can add heat but cannot actively cool the box.
What to look for
- Compare feedback with always-on operation.
- Start above and below the target.
Explain what you noticed
A different system fills a tank. Its sensor already reads above the target level. What fits the stop-at-target feedback rule?
Keep this idea: A feedback loop uses measured results to decide a later action.
Follow the sources
- NASA Goddard — Implementation of a Self-Controlling Heater
- NASA JPL — Robotics: Making a Self-Driving Rover
Source material checked 2026-10-28. Explanations and activities by Nepedia. Source links do not imply endorsement.
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