servomechanism

servomechanism automatic device for the control of a large power output by means of a small power input or for maintaining correct operating conditions in a mechanism. It is a type of feedback control system. The constant speed control system of a DC motor is a servomechanism that monitors any variations in the motor's speed so that it can quickly and automatically return the speed to its correct value. Servomechanisms are also used for the control systems of guided missiles, aircraft, and manufacturing machinery.

servomechanism Device that provides remote control to activate a mechanism. An input signal, such as a radio impulse or mechanical movement, converts into a mechanical output such as a lever movement or amplified hydraulic force. The device usually forms part of a control system. Some servomechanisms, such as the autopilot of an aircraft, incorporate a feedback mechanism that makes them independent of human control.