A device that converts a control signal into mechanical motion.

• Operates mechanisms such as valves via motor, solenoid, or hydraulics.

将控制信号转化为机械运动的装置。

• 通过电机、电磁铁或液压来驱动阀门等机构。

The disk-drive mechanism that positions the read/write head.

• Often a voice-coil or stepper assembly moving the head arm.

磁盘驱动器中用于定位读写磁头的机构。

• 常为音圈或步进电机组件，驱动磁头臂移动。