An active-passive dual mode switchable vehicle suspension system is provided. The suspension system includes a filter, a hydraulic pump, a one-way valve, a power takeoff, a servo valve, a suspension cylinder, an overflow valve, an energy accumulator, a reversing valve, a first pressure sensor, a second pressure sensor, a controller, an oil tank and a displacement sensor. Further related is a switching method for the active-passive dual mode switchable vehicle suspension system. When the active and passive dual-mode switchable vehicle suspension system is switched between modes, an oil pressure in the rodless cavity of the suspension cylinder and an oil pressure in the energy accumulator are adjusted to be equal in advance, so that the stable switching of the active-passive suspension system can be realized, and the vibration of the vehicle body is eliminated when the existing active-passive suspension system is switched. Moreover, the accumulator and overflow valve can be shared in the active and passive suspension mode, thereby effectively reducing the use number of accumulators and overflow valves, greatly saving the layout space of the vehicle body, effectively reducing the total weight of the vehicle body, which is favorable to the lightweight of the vehicle chassis.

A vibration control element includes a nanovoided polymer layer having a first damping coefficient and a first resonance frequency in a first state and a second damping coefficient and a second resonance frequency in a second state, where the first damping coefficient is different from the second damping coefficient and the first resonance frequency is different from the second resonance frequency.

Included are an electromagnetic actuator which includes an electric motor configured to generate drive forces for a damping operation and a telescopic operation; an information acquirer which acquires a stroke velocity of the electromagnetic actuator; a drive force arithmetic part which includes a damping force calculator configured to calculate a target damping force and a telescopic force calculator configured to calculate a target telescopic force, and which obtains a target drive force based on the target damping force and the target telescopic force; and a drive controller which controls drive of the electric motor using the target drive force. The drive force arithmetic part includes an adjuster which performs an adjustment to reduce a telescopic control amount for the target telescopic force based on the stroke velocity acquired by the information acquirer.

A work vehicle includes a vehicle body, running gear to cause the vehicle body to travel, a height adjuster to change a height of a center of gravity of the vehicle body, and a controller configured or programmed to, in accordance with at least one of a turning radius and an angular velocity of the vehicle body during a turn, control the height adjuster to maintain or lower the height of the center of gravity.

A sensory evaluation prediction system includes an input unit that reads an output from a behavior sensor that measures two or more types of pieces of time series information regarding a moving body, a selection unit that selects two or more types of physical quantities from the output from the behavior sensor read by the input unit, a correlation creation unit that creates information showing a correlation in time series between the two or more types of the physical quantities selected by the selection unit, and an evaluation circuit that calculates an evaluation value of a sensory index based on the information showing the correlation in time series.

Disclosed is an automatic vehicle suspension tuning system. The system has a control module to receive user input, an ECU with a processor and a memory, one or more road condition sensors, and one or more controllable suspension system components. The ECU controls the adjustments of the controllable suspension system component in response to user input to the control module as well as input from the road condition sensors during operation of the vehicle. A method of tuning a controllable suspension system component is also disclosed.

A shock absorber includes a suction passage permitting flow only from a reservoir toward a compression-side chamber, a rectification passage permitting flow only from the compression-side chamber toward an extension-side chamber, and a variable valve permitting flow only from the extension-side chamber toward the reservoir. A large chamber as a compression-side pressure chamber communicating with the compression-side chamber and an outer periphery chamber as an extension-side pressure chamber communicating with the extension-side chamber are partitioned in the shock absorber by a free piston that moves slidably within a bottom member serving as a housing. A compression-side pressure-receiving area of the free piston is larger than an extension-side pressure-receiving area. Therefore, even in the uniflow shock absorber with the extension-side chamber and the compression-side chamber at equal pressures during the contraction operation, the damping force is reduced under conditions in which high frequency is input since the free piston moves downward.

A spring-damper system includes at least a differential cylinder (4), a hydraulic accumulator (26) and a control valve device (1, 2). By at least one motor-pump unit (22), pressure fluid can be supplied to the annular end (6) or both the annular end (6) and the piston end (8) of the differential cylinder (4) in a closed circuit using the control valve device (1, 2).

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 system for controlling movement of a vehicle wheel may include a spring and damper assembly coupling the wheel to the vehicle chassis for movement of the wheel relative to the vehicle chassis. The spring and damper assembly may include a spring coupled to a damper member configured to extend and retract the wheel relative to the vehicle chassis. The suspension system may further include a damper actuator located remotely from the spring and damper assembly and configured to modify an amount of damping and/or wheel extension. The suspension system may also include a spring actuator integrated with the damper actuator and configured to control an amount of deflection of the spring and/or to alter a spring rate. The damper actuator may be provided at a location in the vehicle separated from the spring and damper assembly.