Servo (radio control)

A small radio control servo. The plastic case is translucent, revealing the motor and electronics. On top a cross-shaped bellcrank lever provides the mechanical output
Small radio control rotary servo

Servos (also RC servos) are small, cheap, mass-produced servomotors or other actuators used for radio control and small-scale robotics.[citation needed]

Most servos are rotary actuators although other types are available. Linear actuators are sometimes used, although it is more common to use a rotary actuator with a bellcrank and pushrod. Some types, originally used as sail winches for model yachting, can rotate continuously.