Patent attributes
A hydraulic control system has an actuator with first and second chambers, first and second valves having elements movable to fill and drain the first and second chambers, and at least one sensor configured to generate a load signal indicative of a load on the fluid actuator. The system has an interface device movable to generate a desired velocity signal of the actuator. The system has a controller in communication with the first and second valves, the at least one sensor, and the interface device. The controller is configured to move the element of the first valve to a position based on the desired velocity signal and to move the element of the second valve to a position based on the load signal and a desired pressure within the second chamber.