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.

Methods and apparatus are disclosed for adjusting the front to rear ratio of roll damping and/or roll stiffness in a vehicle based on vehicle yaw rate and/or the rate of change of steering wheel angle. Also disclosed are methods and apparatus for dynamically adjusting one or more suspension system control parameters based on one or more of steering wheel angle, rate of change of steering wheel angle and yaw rate.

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 damping force control device 10 comprises vary damping shock absorbers, a detector, and a controller. Each of the shock absorbers sets damping coefficient from a minimum value to a maximum value in order to adjust damping force. The detector detects vertical vibration state quantity relating to vibration of the sprung mass. The controller performs an ordinary control for setting the damping coefficient based on the vertical vibration state quantity and according to a predetermined control law suitable for an assumption that all of the wheels touch ground. The controller performs, when at least one of the wheels is an ungrounded wheel which does not touch the ground and each of the other wheels is a grounded wheel which touches the ground, a specific control for setting the damping coefficient of the shock absorber corresponding to the grounded wheel to a first specific value greater than the minimum value.

A system and method for controlling a vehicle, where the system includes independent driving modules each including a connection device having a rotation center spaced apart from a driving shaft in a forward/rearward direction and configured to connect the wheel and a vehicle body to move the wheel in the forward/rearward or an upward/downward direction, a shock absorber extending in a longitudinal direction and configured to contract or stretch, to connect the vehicle body and the connection device, and to restrict an upward/downward movement of the connection device, and a driving device configured to rotate the wheel, a road surface detector configured to detect a height displacement or a state of a road, and a controller configured to control velocities of the front and rear wheels of the independent driving modules, and to change a height of the vehicle based on the height displacement or the state of the road.

The present invention achieves a technique that not only makes it possible to reduce sensor-related cost but also makes it possible to estimate a ground contact load of a vehicle with sufficiently high accuracy. A ground contact load estimation device (100) causes an acquisition section to acquire a physical quantity related to a vehicle, causes a reference inertia load calculation section (111) to calculate a reference inertia load with use of the physical quantity, uses the physical quantity to cause a correction value calculation section (112) to calculate an inertia load correction value, and causes an inertia load estimation section (110) to estimate an inertia load by adding the inertia load correction value to the reference inertia load.

System and method for improving braking efficiency by increasing the magnitude of a frictional force between a tire of a vehicle wheel and a road surface. Braking efficiency may be improved by controlling the normal force applied on the wheel, with an active suspension actuator, based on the wheel's slip ratio.

A control device is configured to control a damping force of a damping device using a difference between a front-rear acceleration of a vehicle main body and a rotational acceleration of a vehicle wheel, the damping device being configured to dampen a force generated between the vehicle main body and the vehicle wheel.

An air suspension system which includes the ability to adjust the working air volume, pressure, and spring rate of one or more air springs to reduce or eliminate various types of vehicle oscillations. Switchable or variable volume air spring assemblies have the ability to change air spring volumes, which results in changes in air spring rates, and therefore changes in normal loads applied to each wheel. Changes in wheel normal loads change wheel traction (slip) and vehicle dynamics (pitch, roll, yaw displacement, rate and acceleration). The spring rate of one or more of the air spring assemblies is adjusted automatically when a vehicle oscillation is detected. This vehicle oscillation is calculated from the raw vehicle signals, or another vehicle module may detect the oscillation and send a command to the air suspension module to change the spring rates. This changes the natural frequency of the vehicle, dampening the oscillation.

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.