Electromechanical actuators are mechanical actuators where the control knob or handle has been replaced by an electric motor. The rotary motion of the motor is converted into linear displacement. The principle operation in most electromechanical actuators is based on the inclined plane concept. The threads of the lead screw are used as a ramp that converts the small rotational force by magnifying it over a long distance. This enables a large load to be moved over a small distance.
The simplified design of the motor motion is mechanically converted into linear displacement. Variations on electromechanical actuators have been devised to achieve higher mechanical efficiency, speed operation, and increase load capacity. Designs will differ from manufacturer to manufacturer, but in most designs the lead screw and the nut are incorporated into the motion.