Abstract: An example hydraulic system has: a hydraulic cylinder actuator having a cylinder and a piston axially movable in the cylinder, wherein the piston has a piston head that divides an internal space of the cylinder into a first chamber and a second chamber; a fluid reservoir; a pilot pressure source that generates a pilot fluid signal; and a valve assembly controlling fluid flow to and from the hydraulic cylinder actuator, wherein the valve assembly has a first workport fluidly coupled to the first chamber, a second workport fluidly coupled to the second chamber, a reservoir port fluidly coupled to the fluid reservoir, and a pilot port fluidly coupled to the pilot pressure source to receive the pilot fluid signal, wherein the pilot fluid signal actuates the valve assembly to fluidly couple the first workport and the second workport to the reservoir port, thereby operating the piston in a float mode.

Abstract: An example control system includes: a source of fluid; a cylinder actuator having: (i) cylinder, and (ii) a piston movable within the cylinder and dividing an internal space of the cylinder into a first chamber and a second chamber; a pressure control valve; a pilot-operated valve having a pilot port that is fluidly coupled to the source; and a proportional control valve configured to fluidly couple the source of fluid to the second chamber.

Abstract: An example control system includes a cylinder actuator comprising a cylinder, a piston movable within the cylinder and configured to be coupled to a surface engaging implement, and a chamber within the cylinder configured to receive fluid to apply a fluid force on the piston; a proportional control valve configured to control fluid flow from a source of fluid to the chamber; a position sensor coupled to the cylinder actuator and configured to provide position sensor information indicative of a position of the piston; and a controller having access to a desired surface engagement position for the surface engaging implement, wherein the controller is configured to receive the position sensor information, and send a valve command signal to the proportional control valve to change the fluid force applied to the piston to achieve the desired surface engagement position.