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 of the suspension system 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 increase a pressure of hydraulic fluid in a first portion of the suspension system including an accumulator, where the valve control module is configured to decrease the pressure in the first portion after the increase; and a diagnosis module configured to selectively diagnose a fault in the accumulator based on a pressure during the decrease.

A vehicle incorporates a gravity-assist energy harvesting suspension system including one or more gravitational positive displacement pumps. The positive displacement pump has a cylinder and a reciprocating piston inside the cylinder. The piston is adapted for movement along a compression stroke and an opposite extension stroke in response to a gravitational bounce of the vehicle when in motion. A turbine comprising a rotor shaft and attached blades is mounted relative to a distal end of a fluid outlet hose connected to the pump. Fluid discharged through the outlet hose acts on the blades, thereby moving and imparting rotational energy to the rotor shaft. A generator is operatively connected to the turbine, and is adapted for converting the rotational energy generated by the rotor shaft to electrical energy.

A vehicle incorporates a gravity-assist energy harvesting suspension system including one or more gravitational positive displacement pumps. The positive displacement pump has a cylinder and a reciprocating piston inside the cylinder. The piston is adapted for movement along a compression stroke and an opposite extension stroke in response to a gravitational bounce of the vehicle when in motion. A turbine comprising a rotor shaft and attached blades is mounted relative to a distal end of a fluid outlet hose connected to the pump. Fluid discharged through the outlet hose acts on the blades, thereby moving and imparting rotational energy to the rotor shaft. A generator is operatively connected to the turbine, and is adapted for converting the rotational energy generated by the rotor shaft to electrical energy.

A shock absorber comprising a generally tubular body defining a working chamber. A piston is slidable in the working chamber and separates a compression chamber from a rebound chamber of the working chamber. The working chamber contains damping fluid. The shock absorber comprises an electric generator fitted thereto. The generator comprises a turbine rotatably coupled to at least one magnet and coils adjacent the magnet. The shock absorber comprising a turbine flow path between the compression chamber and the rebound chamber, the turbine being supported for rotation in the turbine flow path driven to rotate by flow of damping fluid. Preferably the turbine flow path comprises a compression flow path and a rebound flow path and a turbine chamber, the compression flow path providing for flow of damping fluid from the compression chamber though the turbine chamber to the rebound chamber. One way valves are positioned in the compression and rebound flow paths so that flow only occurs in a respective flow path during compression and rebound of the piston. Movement of said damping fluid though either of said compression flow path or said rebound flow path causes the turbine to rotate in only one rotary direction to thereby generate an electric current in said at least one coil.

A shock absorber comprising a generally tubular body defining a working chamber. A piston is slidable in the working chamber and separates a compression chamber from a rebound chamber of the working chamber. The working chamber contains damping fluid. The shock absorber comprises an electric generator fitted thereto. The generator comprises a turbine rotatably coupled to at least one magnet and coils adjacent the magnet. The shock absorber comprising a turbine flow path between the compression chamber and the rebound chamber, the turbine being supported for rotation in the turbine flow path driven to rotate by flow of damping fluid. Preferably the turbine flow path comprises a compression flow path and a rebound flow path and a turbine chamber, the compression flow path providing for flow of damping fluid from the compression chamber though the turbine chamber to the rebound chamber. One way valves are positioned in the compression and rebound flow paths so that flow only occurs in a respective flow path during compression and rebound of the piston. Movement of said damping fluid though either of said compression flow path or said rebound flow path causes the turbine to rotate in only one rotary direction to thereby generate an electric current in said at least one coil.

A vehicle height adjustment apparatus includes a control device. The control device controls the opening degree of the solenoid valve to allow a movement amount of the support member to reach a movement amount target value that corresponds to the vehicle height set in advance, in accordance with the weight applied to the vehicle. The control device controls the opening degree of the solenoid valve to change the movement amount of the support member based on a difference between a value based on the information related to the vehicle height and a vehicle height-related target value, on condition that the movement amount of the support member reaches the movement amount target value and the value based on the information related to the vehicle height obtained by the information obtaining device does not reach the vehicle height-related target value that corresponds to the vehicle height set in advance.

A vibration damper with a piston, a piston rod fastened to the piston, a working chamber divided by the piston into a first working chamber and second working chamber, and a generator drivable by movement of the piston rod. The damping force of the vibration damper can be influenced by energization of the generator. An energizable component part is provided that short-circuits the windings of the generator when unenergized and cancels the short circuit when energized.

A vibration damper with a piston, a piston rod fastened to the piston, a working chamber divided by the piston into a first working chamber and second working chamber, and a generator drivable by movement of the piston rod. The damping force of the vibration damper can be influenced by energization of the generator. An energizable component part is provided that short-circuits the windings of the generator when unenergized and cancels the short circuit when energized.

An electromagnetic damper is attached to a vehicle and causes oscillation damping force using a motor driven with energy from a power source. The electromagnetic damper includes an electrical circuit that causes a coil of the motor to be short-circuited in a state where the energy from the power source to the motor is interrupted.

A multi-axle transport trailer having a plurality of axles includes a suspension comprising air bags associated with each axle, the air bags in communication with an air source, wherein air bags associated with different axles are capable of having different air pressures therein. The trailer further optionally includes a steering system associated with at least one axle, the axle including a tie rod connected between wheels on both ends of the axle, the steering system comprising cylinders configured to articulate the wheels, and a sensing device configured to monitor movement of the tie rod and facilitate actuating the cylinders to turn the wheels.