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.

An object of the present invention is to provide a vehicle motion state estimation device capable of estimating a vertical momentum of a vehicle with high accuracy from a wheel speed sensor signal during traveling such as acceleration or deceleration, turning, or the like where wheel slips in longitudinal and lateral directions occur. The present invention estimates and removes a variation component caused by a wheel slip from variation components of a wheel speed sensor signal to extract a variation component caused by a displacement of a suspension, and estimates a vertical momentum of a vehicle from the extracted variation component caused by the displacement of the suspension.

A method for controlling a suspension system of a vehicle, as well as suspension systems, and a vehicle including a suspension system is provided. The suspension system may include at least one adjustable damping device that is controlled via a control signal, such as from a controller of the suspension system, in order to dynamically adjust the damping characteristic of the damping device. The control signal may be generated on the basis of at least one of current driving dynamics data and optically recorded information about an area of a ground surface.

A damper control method for a vehicle may achieve normal control of dampers by maintaining the ride comfort enhancement effect of the ECS while reducing manufacturing costs in accordance with a reduction in the number of sensors through elimination of wheel G-sensors.

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 method for estimating damping characteristics of shock absorbers in an active or semi-active suspension involves providing a reference model of a nominal relation between a road severity index related to vertical acceleration values, and the mean driving current of the control valves of the shock absorbers, acquiring respective relative acceleration or speed data of at least the front wheels of the vehicle with respect to the vehicle body, determining a value of the road severity index starting from relative acceleration or speed data of the front wheels of the vehicle with respect to the vehicle body, acquiring values representative of the mean driving current of the control valve of each shock absorber, comparing acquired value of the mean driving current with an expected value of the nominal mean driving current determined as a function of the road severity index according to the reference model, and determining a degradation condition if the acquired value does not correspond to the expected value.

A suspension system includes a primary actuator, an inertial actuator, and a controller. The primary actuator applies force between a sprung mass and an unsprung mass of a vehicle to control movement therebetween. The inertial actuator applies force between the unsprung mass and a reaction mass to damp movement of the unsprung mass. The inertial actuator has a threshold capacity. The controller controls the primary actuator and the inertial actuator. The controller determines a required damping of the movement of the unsprung mass, and apportions the required damping between the primary actuator and the inertial actuator.

Provided is an electric suspension device including an electromagnetic actuator that is provided between a body and wheel of a vehicle and generates damping force for damping vibration of the body. It includes: an information acquisition unit that acquires information on a wheel speed and a sprung speed of the vehicle; an estimation unit that estimates a stroke speed of the actuator based on the wheel speed; a determination unit that determines whether a wheel slip has occurred; and an orientation control unit that performs orientation control of the vehicle based on the sprung speed and the estimated stroke speed. When a wheel slip occurs, the orientation control unit performs orientation control of the vehicle based on a fixed stroke speed whose direction is the same as a direction of the sprung speed and whose magnitude is set at a predetermined fixed value, instead of the estimated stroke speed.

Provided is an electric suspension device including an electromagnetic actuator that is provided between a body and wheel of a vehicle and generates damping force for damping vibration of the body. It includes: an information acquisition unit that acquires information on the vehicle's sprung speed, pitch rate, and roll rate; a bounce target value computation unit that computes a bounce target value for controlling the vehicle's bounce orientation based on the sprung speed; a pitch target value computation unit that computes a pitch target value for controlling the vehicle's pitch orientation based on the pitch rate; a roll target value computation unit that computes a roll target value for controlling the vehicle's roll orientation based on the roll rate; and a driving control unit that controls driving of the actuator with a control target load which is based on a sum of the bounce, pitch, and roll target values.

Provided is an electric suspension device including an electromagnetic actuator that is provided between a body and wheel of a vehicle and generates damping force for damping vibration of the body. It includes: an information acquisition unit that acquires information on a sprung speed and sprung acceleration of the vehicle; a bounce target value computation unit that computes a bounce target value for controlling the vehicle's bounce orientation based on the sprung speed; and a driving control unit that controls driving of the actuator with a control target load which is based on the bounce target value. The bounce target value computation unit has a bounce target load map in which the bounce target value is associated with the sprung speed. The bounce target value computation unit adjusts a width of a dead zone set in the map based on the information on the sprung speed and sprung acceleration.