Provided is a damper with which the energy efficiency for attenuating input vibration corresponding to the unsprung resonance frequency and the sprung resonance frequency can be improved. Also provided is a method for manufacturing this damper. In this damper the electrical resonance frequency, as specified by the inductance of an electromagnetic motor and the capacitance of a capacitor, is set within 20% of the unsprung resonance frequency, thereby enabling the input vibration corresponding to the sprung resonance frequency as well as the input vibration corresponding to the unsprung resonance frequency to be reduced.

A method of on-demand energy delivery to an active suspension system is disclosed. The suspension system includes an actuator body, a hydraulic pump, an electric motor, a plurality of sensors, an energy storage facility, and a controller. The method includes disposing an active suspension system in a vehicle between a wheel mount and a vehicle body, detecting a wheel event requiring control of the active suspension; and sourcing energy from the energy storage facility and delivering it to the electric motor in response to the wheel event.

The invention relates to a method for controlling a flow from a source of pressurized air to an air bag of a pneumatic suspension arrangement in a vehicle. The method comprises obtaining a set of vehicle condition signals comprising at least two vehicle condition signals, each vehicle condition signal being indicative of an individual current condition associated with said vehicle. The method further comprises, on the basis of said set of vehicle condition signals, determining whether or not there is a need to supply the air bag with air from the source of pressurized air. The method further comprises, in response to determining that there is not a need to supply the air bag with air from the source of pressurized air, preventing pressurized air to be fed from said source of pressurized air to said air bag.

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 hydraulic-mechatronic system, for a vehicle that is connected to a target system, includes a housing with a fluid reservoir containing fluid, a communication port, a hydraulic pump, an electric motor for driving the hydraulic pump, at least one check valve, and a relief valve fluidly connected to the target system and the fluid reservoir. The relief valve moves between a first valve position, which is inactive and directs fluid to the communication port, and at least a second valve position, which is active and directs fluid from the communication port to the fluid reservoir. The hydraulic pump may rotate in forward and reverse directions. During operation of the hydraulic pump in the reverse direction, the relief valve is active such that the hydraulic-mechatronic system limits delivery of fluid through the communication port and instead directs fluid flow into the fluid reservoir of the housing.

Methods and apparatus to determine vehicle weight are disclosed. An example apparatus includes a vehicle controller configured to control a motor operatively coupled to a suspension system to raise or lower a vehicle. The vehicle controller is to also determine a first parameter of the motor while controlling the motor to raise or lower the vehicle when the vehicle is unloaded. The vehicle controller is to also determine a second parameter of the motor while controlling the motor to raise or lower the vehicle when the vehicle is at least partially loaded. The vehicle controller is to also calculate a weight of the vehicle based on the first and second parameters of the motor.

A hydraulic actuator circuit is disclosed for use with first and second shock absorbers, which each may include a piston disposed within a housing. The piston helps define upper and lower working chambers. The circuit may have a motor, a first pump, driven by the motor, and is associated with the first shock absorber and the motor. A second pump, driven by the motor, may be associated with the second shock absorber. A first accumulator communicates with both of the first and second pumps. A first switch valve may assist in controlling fluid flow into the chambers of the first shock absorber. A second switch valve may assist in controlling fluid flow into the chambers of the second shock absorber.

A height adjustment system for a vehicle includes: a reservoir configured to hold hydraulic fluid; at least one lift actuator operably disposed between a wheel and a chassis element of the vehicle for adjusting the height of the vehicle; a supply pump having an inlet port in fluid communication with the reservoir and configured to transfer the hydraulic fluid to the at least one lift actuator via a manifold; a supply check valve configured to allow fluid flow from an outlet of the supply pump to the manifold while blocking fluid flow in an opposite direction; and at least one of: a supply pump isolation valve configured to selectively bypass hydraulic fluid around the supply check valve, or a secondary actuator isolation valve configured to selectively control fluid flow between the at least one lift actuator and the inlet port of the supply pump.

Method to control active shock absorbers of a road vehicle. Each active shock absorber is part of a suspension connecting a frame to a hub of a wheel and is provided with an actuator. The control method comprises the steps of: determining a longitudinal acceleration and a transverse acceleration of the road vehicle; establishing a desired lowering of a centre of gravity of the road vehicle depending on the longitudinal acceleration and on the transverse acceleration; and controlling the actuator of each active shock absorber so as to obtain the desired lowering of the centre of gravity.

A method of on-demand energy delivery to an active suspension system is disclosed. The suspension system includes an actuator body, a hydraulic pump, an electric motor, a plurality of sensors, an energy storage facility, and a controller. The method includes disposing an active suspension system in a vehicle between a wheel mount and a vehicle body, detecting a wheel event requiring control of the active suspension; and sourcing energy from the energy storage facility and delivering it to the electric motor in response to the wheel event.