A method of controlling a suspension system of a vehicle includes identifying an amplitude and a frequency of at least one harmonic event in a topology of a surface to be traversed by the vehicle, and, with a controller, altering at least one response characteristic of at least one adjustable component of the suspension system based on at least one of the amplitude and frequency of the harmonic event. Systems and methods relate to controlling vehicle suspension systems.

A regenerative shock absorber that include a housing and a piston that moves at least partially through the housing when the shock is compressed or extended from a rest position. When the piston moves, hydraulic fluid is pressurized and drives a hydraulic motor. The hydraulic motor, in turn, drives an electric generator that produced electric energy. The electric energy may be provided to a vehicle, among other things. The regenerative shock absorber may also provide ride performance that comparable to or exceeds that of conventional shock absorbers.

A vehicle fluid supply system includes a fluid supply valve configured to control fluid flow from a vehicle fluid supply to a trunk conduit in fluid communication with a vehicle tire inflation system; and a lift axle valve configured to control fluid flow from the trunk conduit to a lift axle deployment system.

A regenerative shock absorber that include a housing and a piston that moves at least partially through the housing when the shock is compressed or extended from a rest position. When the piston moves, hydraulic fluid is pressurized and drives a hydraulic motor. The hydraulic motor, in turn, drives an electric generator that produced electric energy. The electric energy may be provided to a vehicle, among other things. The regenerative shock absorber may also provide ride performance that comparable to or exceeds that of conventional shock absorbers.

A bogie positioning system and method for a work machine. The bogie positioning system adapted to selectively engage a wheel of a work machine to a ground surface through a bogie assembly wherein the bogie assembly may have a front wheel coupled to a rear wheel through a bogie coupling mechanism. The bogie coupling mechanism comprising a beam with a rotary joint. The rotary joint allowing the front wheel to rotate about a rotary axis relative to the rear wheel. The beam is coupled to a chassis of the work machine with at least one actuator coupled to the beam. A control unit is in communication with the bogie assembly, a user input interface, and a plurality of sensors, generating command signals to actuate the actuator based on the input signals, thereby selectively engaging the front wheel or the rear wheel with the ground surface.

A method and apparatus are disclosed for cooling damping fluid in a vehicle suspension damper unit. A damping unit includes a piston mounted in a fluid cylinder. A bypass fluid circuit having an integrated cooling assembly disposed therein is fluidly coupled to the fluid cylinder at axial locations that, at least at one point in the piston stroke, are located on opposite sides of the piston. The cooling assembly may include a cylinder having cooling fins thermally coupled to an exterior surface of the cylinder and made of a thermally conductive material. The bypass channel may include a check valve that permits fluid flow in only one direction through the bypass channel. The check valve may be remotely operated, either manually or automatically by an electronic controller. A vehicle suspension system may implement one or more damper units throughout the vehicle, controlled separately or collectively, automatically or manually.

A suspension system includes a spring assembly including a gas spring and an accumulator, and a controller. The accumulator is coupled to the gas spring and includes a bladder. The accumulator has a compressed state and an uncompressed state. The controller is configured to a) determine a target amount of gas in the spring assembly and b) adjust the amount of gas in the spring assembly towards the target amount of gas based on a pressure difference across the bladder.

Systems and methods for controlling a gas spring in a suspension system. The suspension system includes a gas spring and an accumulator coupled to the gas spring and having a bladder. The accumulator may be in a compressed state and an uncompressed state based on a pressure difference across the bladder. A target amount of gas in the gas spring is determined. The amount of gas in the gas spring is adjusted towards the target amount of gas in accordance with a pressure difference across the bladder based on the difference between the first pressure and the second pressure.

A method and apparatus are disclosed for cooling damping fluid in a vehicle suspension damper unit. A damping unit includes a piston mounted in a fluid cylinder. A bypass fluid circuit having an integrated cooling assembly disposed therein is fluidly coupled to the fluid cylinder at axial locations that, at least at one point in the piston stroke, are located on opposite sides of the piston. The cooling assembly may include a cylinder having cooling fins thermally coupled to an exterior surface of the cylinder and made of a thermally conductive material. The bypass channel may include a check valve that permits fluid flow in only one direction through the bypass channel. The check valve may be remotely operated, either manually or automatically by an electronic controller. A vehicle suspension system may implement one or more damper units throughout the vehicle, controlled separately or collectively, automatically or manually.

A bogie positioning system and method for a work machine. The bogie positioning system adapted to selectively engage a wheel of a work machine to a ground surface through a bogie assembly wherein the bogie assembly may have a front wheel coupled to a rear wheel through a bogie coupling mechanism. The bogie coupling mechanism comprising a beam with a rotary joint. The rotary joint allowing the front wheel to rotate about a rotary axis relative to the rear wheel. The beam is coupled to a chassis of the work machine with at least one actuator coupled to the beam. A control unit is in communication with the bogie assembly, a user input interface, and a plurality of sensors, generating command signals to actuate the actuator based on the input signals, thereby selectively engaging the front wheel or the rear wheel with the ground surface.