A suspension system for a vehicle includes a first suspension arrangement including a first hydraulic cylinder; a second suspension arrangement including a second hydraulic cylinder; and a valve unit between the first and second hydraulic cylinders. The valve unit is controllable between a first state in which a piston side of the first hydraulic cylinder and a piston rod side of the second hydraulic cylinder are in fluid communication, and a piston rod side of the first hydraulic cylinder and a piston side of the second hydraulic cylinder are in fluid communication; and a second state in which the piston side of the first hydraulic cylinder and the piston side of the second hydraulic cylinder are in fluid communication, and the piston rod side of the first hydraulic cylinder and the piston rod side of the second hydraulic cylinder are in fluid communication.

A hydraulic circuit for a lifting system of a propulsion system for a construction machine having multiple independent propulsors can comprise a plurality of hydraulic cylinders each comprising a piston and a rod for coupling to a propulsor, a plurality of fluid lines coupling each of the plurality of hydraulic cylinders in series, wherein movement of one piston hydraulically causes movement of a subsequent piston in an opposite direction, and a plurality of flow control devices positioned within the plurality of fluid lines such that a flow control device is positioned between adjacent hydraulic cylinders, each flow control device comprising an intermediate body configured to smooth flow of hydraulic fluid between adjacent hydraulic cylinders without directly coupling one cylinder to another.

An exemplary energy delivery system includes a housing. The housing includes a linear motor including a translational member and an electromagnetic field generating member. Energization of the electromagnetic field generating member induces translation of the translational member along a longitudinal axis of the linear motor. The housing further includes a first cylinder including a first chamber and a movable first piston and a second cylinder including a second chamber and a movable second piston. The first and second cylinders are coupled in-line with the linear motor within the housing and translation of the translational member along the longitudinal axis translates the first piston within the first chamber in a first direction and translates the second piston within the second chamber in a second direction opposite the first direction.

A hydraulic system includes a hydraulic pump. A first hydraulic shock is coupled to a first port of the hydraulic pump. A second hydraulic shock is coupled to a second port of the hydraulic pump. A first hydraulic cylinder is coupled to the first port of the hydraulic pump. A second hydraulic cylinder is coupled to the second port of the hydraulic pump. A first valve is coupled between the first hydraulic cylinder and second hydraulic cylinder. The first valve can be actuated by a computer system or can be a ball and spring check valve. A second valve is coupled between the first hydraulic cylinder and second hydraulic cylinder. A flow direction of the second valve is opposite a flow direction of the first valve. A first piston is disposed in the first hydraulic cylinder, and a second piston is disposed in the second hydraulic cylinder.

A hydraulic system includes a hydraulic pump. A first hydraulic shock is coupled to a first port of the hydraulic pump. A second hydraulic shock is coupled to a second port of the hydraulic pump. A first hydraulic cylinder is coupled to the first port of the hydraulic pump. A second hydraulic cylinder is coupled to the second port of the hydraulic pump. A first valve is coupled between the first hydraulic cylinder and second hydraulic cylinder. The first valve can be actuated by a computer system or can be a ball and spring check valve. A second valve is coupled between the first hydraulic cylinder and second hydraulic cylinder. A flow direction of the second valve is opposite a flow direction of the first valve. A first piston is disposed in the first hydraulic cylinder, and a second piston is disposed in the second hydraulic cylinder.

A system for grading filling of a suspension system includes: a pump control module configured to, during first and second periods, operate an electric pump of the suspension system in first and second directions and decreasing and increasing hydraulic fluid pressure within the suspension system, respectively; a monitoring module configured to: store a first pressure of hydraulic fluid within the suspension system measured using a pressure sensor when the first pressure is less than or equal a first predetermined pressure while the pump is operated in the first direction; and store a second pressure measured using the pressure sensor when the second pressure is greater than or equal a second predetermined pressure while the pump is operated in the second direction; and a grade module configured to determine a grade value for the filling of the suspension system based on the first and second pressures.

A machine comprises a frame, a plurality of ground engaging units, a plurality of moveable legs, and a hydraulic system. A first ground engaging unit and a second ground engaging unit connect a first leg and a second leg, respectively, with the frame. The hydraulic system controls heights of the plurality of moveable legs. The hydraulic system comprises a fluid circuit to control fluid between the first and second legs, a load holding valve to control fluid flow into the fluid circuit, and first and second relief valves to control flow of fluid between the first and second legs in opposite directions. A method for controlling slope of a construction machine comprises activating a relief valve connecting right and left lifting cylinders to control flow of hydraulic fluid between the lifting cylinders to control retraction of one of the lifting cylinders from retracting.

A state module selectively sets a present state to a first state in a predetermined order of states; a valve control module determines first target open and closed states for valves of a suspension system based on the present state and opens and closes the valves according to the first target open and closed states, respectively; a pump control module configured to, when the valves are in the first target open and closed states, respectively, selectively operate an electric pump of the suspension system in a first direction and pump hydraulic fluid toward the suspension system; and a diagnosis module configured to: record first and second values of pressures within the suspension system measured using pressure sensors, respectively, before and after the operation of the electric pump in the first direction, respectively; and selectively diagnose faults in a first subset of the valves based on whether pressure increases occurred.

A system includes: a state module configured to selectively set a present state to a first state; a valve control module configured to determine first target open and closed states for valves of a suspension system based on the present state and to open and close the valves according to the first target open and closed states, respectively; a pump control module configured to, when the valves are in the first target open and closed states, respectively, selectively operate an electric pump in a first direction to increase hydraulic fluid pressure in a first portion of the suspension system; and a leak module configured to selectively diagnose a leak in a first one of the valves associated with the first state based on a first pressure in the first portion of the suspension system while the valves are open and closed according to the first target open and closed states.

A suspension system and associated control methods for improving the effectiveness of driver assistance systems is disclosed where the driver assistance systems can generate and send requests to a suspension control unit (SCU) of the suspension system to actuate (e.g., close) one or more comfort valves in the suspension system to increase the roll stiffness and/or pitch stiffness of the suspension system when the driver assistance systems are taking corrective action. As part of a two-way communication between the suspension control unit (SCU) and the driver assistance systems, the suspension control unit (SCU) communicates target stiffnesses and/or calculated effective stiffnesses to the driver assistance systems, which is used to update the vehicle stability models used by the driver assistance systems.