Engineers often utilize feedback loops when designing control systems. A feedback loop is a control that integrates the system’s output back into an input stream to control future operations. Here are some common examples of a feedback loop:
- Your home’s thermostat: As the temperature drops below a set target, the thermostat provides input to the furnace to activate and warm your home. When the temperature climbs above the desired setpoint, the thermostat signals your furnace to turn off.
- A microphone sends an input signal into an amplifier/speaker and the speaker generates sound. If the microphone is held too close to the speaker, it captures the sound from the speaker and creates an unintended “circular” loop; this generates an unpleasant “squeal” we are all familiar with.
- The NFL draft: Every year, teams with the worst record are provided the earlier opportunities to select the best players coming out of college. As these teams “rebuild” with more talented players, they should eventually improve their win-loss record and move down in the draft (in theory).