Before revision: In mechanical engineering and control engineering, a servomechanism (also called a servo (to be differentiated from a servomotor, which may also be called " servo ") or a servosystem ) is a control system for the position and its time derivatives (for example, velocity) of a mechanical system using .
After revision: In mechanical engineering and control engineering, a servomechanism (also called a servo (to be differentiated from a servomotor, which may also be called " servo system, or simply servo ) is a control system for the position and its time derivatives , such as velocity, of a mechanical system .