What Does Actuator Mean?

An actuator is a device that moves or controls some mechanism. An actuator turns a control signal into mechanical action such as an electric motor. Actuators may be based on hydraulic, pneumatic, electric, thermal or mechanical means, but are increasingly being driven by software. An actuator ties a control system to its environment.


Techopedia Explains Actuator

In a mechanical device, an actuator is a component that turns the control signal into movement.

Examples of actuators include:

  • Electric motors
  • Solenoids
  • Hard drive stepper motors
  • Comb drives

Actuators may be powered by electric current, hydraulic fluid or pneumatic pressure. In embedded systems, the control signal comes from a microcontroller programmed by software. Device drivers send input to a peripheral device, such as a printer. While actuators typically provide circular motion, they can convert circular motion into linear motion via screws and wheel-and-axle devices. An example of the latter is a rack and pinion system.


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Margaret Rouse
Technology Expert

Margaret is an award-winning technical writer and teacher known for her ability to explain complex technical subjects to a non-technical business audience. Over the past twenty years, her IT definitions have been published by Que in an encyclopedia of technology terms and cited in articles by the New York Times, Time Magazine, USA Today, ZDNet, PC Magazine, and Discovery Magazine. She joined Techopedia in 2011. Margaret's idea of a fun day is helping IT and business professionals learn to speak each other’s highly specialized languages.