A device for controlling the motion of a fluid actuator which includes an electrically operated control valve that controls the flow of a pressurized fluid to and from the fluid actuator in response to signals generated by an actuator controller which uses an on-board, user programmable microprocessor where the user can download various control algorithms into the microprocessor for controlling the motion of the actuator based on such parameters as fluid pressure and flow rates and actuator displacement. Various external sensors can be connected to the controller for monitoring and control purposes using various signal interfaces such as an analog to digital converter or an SSI interface. A local communication bus is used to communicate with one or more slave actuators each having their own electrically operated control valve that controls the flow of a pressurized fluid to and from the slave actuator in response to control signals generated by the controller and sent to the slave control valve over the local bus. Sensors are used to measure various operating parameters of the slave actuator and generate signals that are sent to the controller over the local bus. A supervisory computer is used to send a high level command signal to the controller where the controller generates a closed loop control signal to one or more fluid actuators.