Cruise Control Servo/Regulator
A servomechanism, sometimes shortened to servo, is an automatic device that uses error-sensing negative feedback to correct the performance of a mechanism and is defined by its function. It usually includes a built-in encoder. A servomechanism is sometimes called a heterostat since it controls a system's behavior by means of heterostasis.
Moreover, the term correctly applies only to systems where the feedback or error-correction signals help control mechanical position, speed or other parameters. For example, an automotive power window control is not a servomechanism, as there is no automatic feedback that controls position—the operator does this by observation. By contrast a car's cruise control uses closed loop feedback, which classifies it as a servomechanism.
Howbeit, the cruise control system is designed to make highway driving less tiring. It allows you to select a speed and take your foot off the accelerator pedal. This type of cruise control is ideal for open road driving when there is little traffic, or the traffic is rolling along at a fairly constant speed.