A servomechanism, or servo's an automatic device that uses error-sensing feedback to correct the performance of a mechanism. The term correctly applies only to systems where the feedback or error-correction signals help control mechanical position or other parameters. For example, an automotive power window control isn't a servomechanism, as there's no automatic feedback which controls position—the operator does this by observation. By contrast the car's cruise control uses closed loop fe… (More on Servomechanism)