The invention relates to a method for monitoring a state of wear of a damping device within a system. The system includes a vehicle seat having a first portion which is movably mounted in at least one direction with respect to a second portion, a damping device for damping oscillations is arranged between the first portion and the second portion, and a first sensor that determines an instantaneous relative position of the first portion with respect to the second portion. A displacement function in relation to the relative position of the first portion with respect to the second portion is defined as a function of time, and a current value of the displacement function is determined at selected intervals and summed. The sum is compared with a predetermined first limit.

Provided is an electric suspension device including an electromagnetic actuator that is provided between a body and wheel of a vehicle and generates a load for damping vibration of the body. It includes: a camera that detects preview image information of a road surface in front of the vehicle; a 3D gyro sensor that detects a sprung speed of the vehicle; a target load computation unit that computes a target load based on the preview image information and the sprung speed; and a load control unit that controls the load of the actuator by using the computed target load. When a detection result based on the preview image information indicates that the front road surface is even but a detection result based on the sprung speed indicates that the front road surface is uneven, the target load computation unit computes the target load based on the sprung speed.

A suspension device includes an actuator capable of generating a thrust force and a controller. The controller includes a first vibration suppression force computation unit configured to obtain a first vibration suppression force from a vertical velocity of a sprung member, a second vibration suppression force computation unit configured to obtain a second vibration suppression force from a vertical velocity of the unsprung member or a relative velocity between the sprung member and the unsprung member, a low-pass filter having a breakpoint frequency between a sprung resonance frequency and an unsprung resonance frequency and processing a signal in the course of obtaining the second vibration suppression force using the second vibration suppression force computation unit, and a target thrust force computation unit configured to obtain a target thrust force of the actuator on the basis of the first vibration suppression force and the second vibration suppression force.

A suspension characteristic is changed depending on a travel state by a simple structure. An ECU uses a vehicle speed-spring constant setting part to calculate a target spring constant depending on a vehicle speed, and uses a spring constant-frequency setting part to calculate a set frequency corresponding to the target spring constant. An oscillation input calculation part generates a signal representing an oscillation input oscillating at the set frequency. A superimposition part sets a value acquired by superimposing the oscillation input on a target driving force to a new target driving force. As a result, the wheel exhibits a minute oscillation in a longitudinal direction, resulting in an input of the minute oscillation to a suspension bush. The suspension bush changes in a spring constant and a damping coefficient depending on the frequency of the input minute oscillation. As a result, the suspension characteristic can be changed.

An active chassis control for a motor vehicle with an adaptive control circuit for reducing body vibrations (A.sub.actual) of the motor vehicle, in which a control unit is integrated, which, depending on a current body vibration (A.sub.actual) or a parameter correlating therewith (a), controls a chassis actuator. The control unit is followed by an adaptive unit which adapts an actuating signal (S) generated by the control unit with a driving speed-dependent scaling factor (f(v)), in particular by generating an adapted actuating signal (S′) with which the chassis actuator can be controlled. Depending on the situation, a factor allowance (Δf) can be added to the driving speed-dependent scaling factor (f(v)) in the event of a significantly greater body vibration (A.sub.o) in order to effectively dampen the significantly greater body vibration (A.sub.o).

Provided a suspension control appratus including a vehicle behavior detection unit (acceleration sensors), an electrorheological damper provided between a vehicle body (1) and each wheel (2), and a controller configured to execute control so that a damping force of each electrorheological damper is adjusted based on a detection result obtained by the vehicle behavior detection unit. The controller includes a target voltage value setting unit (damping force command calculation unit) configured to obtain a target voltage value to be applied to an electrode tube based on the detection result obtained by the vehicle behavior detection unit, a temperature estimation unit configured to detect or estimate temperature of ERF, and a target voltage value correction unit (output limiting unit) configured to change the target voltage value so that a piston speed (V) is adjusted based on a value obtained by the temperature estimation unit.

A suspension control apparatus includes a damping force adjustable shock absorber disposed between a vehicle body and a wheel of a vehicle and capable of adjusting a damping force to be generated, a vertical movement detection device configured to detect a state regarding a vertical movement of a vehicle, and a controller including: a target damping force calculation section configured to calculate a target damping force based on a detection result of the vertical movement detection device, a correction section configured to calculate a corrected damping force, which is acquired by reducing the target damping force when a relative speed is a low speed between a sprung side and an unsprung side of the damping force adjustable shock absorber, and a control signal output section configured to output the control signal corresponding to the corrected damping force to the damping force adjustable shock absorber.

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.

A damping control device for a vehicle calculates a combined control force by adding together a control force when a front wheel passes through a predicted passing position and a control force when a rear wheel passes through a predicted passing position, and calculates a final control force for the front wheel and a final control force for the rear wheel by distributing the combined control force at a predetermined distribution ratio.

A control unit is configured to execute vibration suppression control, in which the control force generation device is controlled based on a target vibration suppression control force when a wheel passes through a predicted wheel passage position, and roll control, in which the control force generation device is controlled based on a target roll control force for reducing roll of the sprung portion based on a roll index value. When the vibration suppression control and the roll control are executed concurrently, the control force generation device is controlled based on the target vibration suppression control force and the target roll control force obtained after at least one of a reduction correction for the target vibration suppression control force and an increase correction for the target roll control force is performed.