Abstract:
An apparatus for controlling a vehicle active suspension system having a plurality of actuatable hydraulic motors, each corner having a motor connecting the sprung mass with its associated unsprung mass. Each motor has an associated spool valve for connecting either of two expandable fluid chambers of said motor to a pump or reservoir. Each corner has an associated force sensor for sensing the force value between its associated unsprung mass and the sprung mass. An analog, closed force loop control circuit provides a valve control signal having a value functionally related to the difference between a sensed force value and a desired force value for a selected corner. The closed loop control circuit includes a variable gain amplifier for controlling the value of the valve control signal as a function of the frequency of variations in the difference between the sensed force value and the desired force value on the selected corner. The amplifier gain is controlled as a function of hub velocity so as to undamp a selected corner and as a function of chassis velocity so as to damp the chassis. A digital processing circuit determines a displacement error value for selected corner. The displacement error value is summed with the valve drive signal. An actuator bump stop arrangement is also provided.
Abstract:
A device for damping the motion sequences of two masses includes sensors for detecting relative motion between the two masses and absolute motion of one of the two masses. A signal processing circuit receiving output signals from the sensors has an output which is dependent on the frequency of the sensed signals. A controllable actuator receives the signal processing circuit output and is connected to the two masses.
Abstract:
A vehicle chassis system control method, comprising the steps of: measuring vehicle yaw rate, vehicle speed, and vehicle lateral acceleration; determining, responsive to the yaw rate, vehicle speed and lateral acceleration, an index ratio; comparing the index ratio to a predetermined threshold indicating a limit above which active chassis control is not desired; and responsive to the comparison, setting a signal indicating termination of active chassis control if the index ratio is above the predetermined threshold.
Abstract:
An adjustable damping system (26) for an automotive vehicle (12) having a damper (10) and sensors (28, 30, 32) for determining the movement of the automotive vehicle (12) and generating a signal representing the movement of the automotive vehicle (12). The adjustable damping system (26) further includes a damper control logic unit 40 for automatically adjusting the damping characteristics of the damper (10) in response to the signal. The adjustable damping system (26) further includes a signal compensation unit (42) which is able to improve the accuracy with which signals representing the movement of the automotive vehicle (12) are determined.
Abstract:
Basing on signals (Vi) representing the vertical movements of the vehicle body at selected points (Pi) of the body, and basing on second signals (Xarvl', Xarvr', Xarhl', Xarhr') representing the relative movements between the wheel units and the body of the vehicle, the inventional system infers selected components of movement of the vehicle body, such as heave, roll and pitch movements or the vertical movement of the body at the front and rear axles as well as the roll movement. These components of movement are weighted differently. Basing on these differently weighted components of movement, second body movements are inferred at the points where the wheel suspension systems attach to the body. By comparison of the second body movements (Vagvl, Vagvr, Vaghl, Vaghr) to the pertaining relative movements between the wheel units and the body there are actuation signals formed for the respective suspension system, in a way such that the selected components of movement can be influenced separately from one another in the sense of a reduction.
Abstract:
An electric control apparatus for a shock absorber disposed between unsprung mass and sprung mass of a suspension mechanism in an automative vehicle and provided with an electrically operated control valve for changing damping characteristics of vertical displacement of the sprung mass relative to the unsprung mass, wherein absolute vertical displacement velocity of the sprung mass and relative vertical displacement velocity of the sprung mass to the unsprung mass are detected to determine a target opening degree of the control valve in accordance with the detected absolute vertical displacement velocity and relative vertical displacement velocity of the sprung mass, and where variation of the target opening degree is allowed in a large range only when the direction of the relative vertical displacement velocity has changed and is restricted in a predetermined small range under other conditions where the shock absorber acts to absorb vibration of the vehicle body.
Abstract:
A system and method for controlling a damping characteristic of at least one shock absorber for an automotive vehicle in which, when direction determining signs of both vertical sprung mass velocity (V) and relative velocity (Sv) between a sprung mass and an unsprung mass are the same, the variable control of the damping characteristic C is carried out at either of extension stroke side (V is plus and Sv is plus) or contraction stroke side (V is minus and Sv is minus) to provide C=.alpha..multidot.V/Sv, and when the direction determining signs of both vertical sprung mass velocity (V) and relative velocity (Sv) between the sprung mass and the unsprung mass are mutually different, the variable control of the damping characteristic C is carried out at either of extension stroke side (V is plus and Sv is minus) or contraction stroke side (V is minus and Sv is plus) to provide C=.alpha..multidot.V.
Abstract:
A shock absorber is connected between a vehicle body and a vehicle wheel. The shock absorber provides a variable damping force. A control apparatus for the shock absorber includes an actuator for adjusting the damping force provided by the shock absorber. A vibration detecting device serves to detect a relative vibration between a spring upper member and a spring lower member. A damping-factor estimating device serves to estimate a damping factor of the shock absorber. A speed estimating device serves to estimate an absolute speed of the spring upper member on the basis of the relative vibration detected by the vibration detecting device and the damping force estimated by the damping-force estimating device. A signal setting device serves to set a drive signal of the actuator on the basis of the absolute spring upper member speed estimated by the speed estimating device.
Abstract:
A method and apparatus for absorbing mechanical shock is disclosed. The apparatus comprises a pressure cylinder forming a working chamber having first and second portions operable to store damping fluid. The apparatus further comprises the first valve for controlling the flow of damping fluid between the first and second portions of the working chamber during compression of the shock absorber. In addition, the apparatus further comprises a pressure chamber in fluid communication with the first portion of the working chamber and the first valve. A solenoid is also provided for regulating the flow of damping fluid between the pressure chamber and the second portion of the working chamber. A second valve is further provided for controlling the flow of damping fluid between the first and second portions of the working chamber during rebound of the shock absorber.
Abstract:
A vehicle control system includes an active suspension mechanism for providing a rolling property of a vehicle in a cornering operation of the vehicle and a suspension control device for controlling the vehicle in accordance with the rolling property provided by the active suspension mechanism and changing from one rolling property to another. A rear wheel steering mechanism steers a rear wheel in connection with steering of a front wheel, and a steering control device controls the steering of the rear wheel in accordance with a predetermined steering property and changes the steering property for the rear wheel. One of the steering property and the rolling property is changed in synchronism with a change in the other of the steering property and the rolling property. When a reverse phase property is provided for the rear wheel as a steering property and a reverse rolling property is provided for the active suspension system, the visibility of the cornering direction and the operability are improved to accomplish an active operation property. Alternatively when a same phase property is provided for the rear wheel as a steering property, the running stability can be improved.