Advics Co., Ltd.

Daihatsu Motor Company, Ltd.

Junya Nagaya

Toshihisa Kato

Yoshiyuki Yasui

Hiroshi Matsuoka

Shinji Tsugawa

Yasuhito Ishida

Tatsuya Yano

Tokio Yakushijin

A motion control device for a vehicle having a braking means for applying a brake toque to a wheel of the vehicle and maintaining a traveling stability of the vehicle by controlling the braking means, the motion control for the vehicle, includes a steering angular velocity obtaining means for obtaining a steering angular velocity of the vehicle, a maximum steering angular velocity calculating means for calculating a maximum steering angular velocity on the basis of the steering angular velocity, a determining means for determining a reference turning state quantity on the basis of the maximum steering angular velocity, an actual turning state quantity obtaining means for obtaining an actual turning state quantity of the vehicle, and a control means for controlling the brake toque on the basis of the reference turning state quantity and the actual turning state quantity.

Motion control device for vehicle

To improve vehicle stability by starting control based on quicker detection of the possibility that a vehicle state will reach an unstable region. It is detected that a vehicle is in a pre-skid state that is the state prior to when the vehicle reaches an unstable region where skid occurs, and brake force is generated in a rear wheel at an outside of a turn when the pre-skid state is detected. As a result of generating this brake force, load applied to the wheels at the outside of the turn increases and lateral force of the vehicle increases. Thus, it is possible to make it more difficult for skid of the vehicle to occur, and so it is possible to inhibit, in advance, gentle deterioration in vehicle behavior such as slow spin. Accordingly, the possibility that a vehicle state has reached an unstable region can be detected earlier.

Vehicle behavior control device

A vehicle steering control device includes a yawing value obtaining unit which obtains a yawing value corresponding to a vehicle yawing motion, a stabilizing force calculating unit which calculates a stabilizing force for assisting an operation of a steering operation member, operated by a driver for steering a steered wheel of the vehicle, in a direction opposite a direction of the vehicle yawing motion, based on the yawing value, and a force applying unit which applies the stabilizing force to the steering operation member in the direction opposite the yawing motion direction, wherein the stabilizing force calculating unit includes a counter-steer value calculating unit which calculates a counter-steer value indicating a degree of steering the steered wheel in the direction opposite the yawing motion direction, and wherein the stabilizing force is adjusted based on the counter-steer value.

Steering control device for vehicle

When the absolute value of the steering angle equals or is greater than a prescribed angle, a vehicle motion control apparatus sets a control gear ratio so that when an estimated vehicle-body speed is equal to or greater than a prescribed value, the control gear ratio becomes a value equal to or greater than a certain value and which increases with estimated vehicle-body speed as the absolute value of the steering angle increases. When the estimated vehicle-body speed is less than the prescribed value, the control gear ratio becomes a value not greater than the certain value and which decreases with estimated vehicle-body speed as the absolute value of the steering angle increases. The apparatus then calculates a target yaw rate making use of the control gear ratio, and controls a braking force applied to each wheel so that the actual yaw rate coincides with the target yaw rate.

Motion control apparatus for a vehicle

In the roll-over preventing control, a vehicle motion control devicecauses inner-wheel braking force, according to the absolute value of an actual lateral acceleration Gy, only on the rear wheel at the inner side of the turning direction when the absolute value |Gy| of the actual lateral acceleration is not less than a rear-wheel-side reference value Gyr and not more than a front-wheel-side reference value Gyf thereby causing height lowering force at the vehicle rear-side section of the inner side of the turning direction. In addition, when the absolute value |Gy| of the actual lateral acceleration becomes not less than the front-wheel-side reference value Gyf, the inner-wheel braking force according to the absolute value |Gy| of the actual lateral acceleration is kept to be caused on the rear wheel at the inner side of the turning direction and outer-wheel braking force according to the absolute value |Gy| of the actual lateral acceleration is also caused on the front wheel at the outer side of the turning direction, thereby forcibly generating a yawing moment on the vehicle in the direction opposite to the turning direction.

Vehicle motion control device

According to a roll increasing tendency estimation apparatus, a state variable is calculated in response to magnitude of a rolling moment of the vehicle, to provide a roll input magnitude, and a state variable is calculated in response to variation in time of the rolling moment, to provide a roll input velocity. A roll increasing tendency of a vehicle is estimated on the basis of a relationship between the calculated roll input magnitude and the calculated roll input velocity. On the basis of a relationship between the roll input magnitude and roll input velocity, at least one of a braking force control and a driving force control may be performed, to restrain the roll increasing tendency of the vehicle.

Roll increasing tendency estimation apparatus

A rolling motion stability control apparatus restrains a roll increasing tendency of a vehicle, with each wheel of the vehicle being braked by a wheel brake device. A first braking force control device is provided for applying a first braking force to the wheel, when the vehicle is turned to one direction. A second braking force control device is provided for applying a second braking force to the wheel, when the vehicle is turned to the other direction. References for starting controls of the first and second braking force control devices are set to be of predetermined values, respectively. The reference for starting the control of the second braking force control device is modified to be smaller than a predetermined value, when the vehicle is turned to the one direction.

Rolling motion stability control apparatus for a vehicle

The vehicle motion control device of the invention utilizes that the detected lateral acceleration Gyd based upon the output from the lateral acceleration sensor takes a value obtained by adding a value corresponding to the roll angle to the actual lateral acceleration based upon the centrifugal force exerted on the vehicle and that the actual lateral acceleration can accurately be calculated and estimated, as the estimated lateral acceleration Gye, based upon the output from the yaw rate sensor, whereby this device judges that there is a tendency in which an excessive roll angle occurs on the vehicle to thereby execute the predetermined roll-over preventing control, when the increasing speed of the detected lateral acceleration Gyd exceeds the first predetermined value and the increasing speed of the estimated lateral acceleration Gye becomes smaller than the second predetermined value (&#x3c;first predetermined value), i.e., when the value of the estimated lateral acceleration Gye is changed from its increasing state to the approximately constant state during when the detected lateral acceleration Gyd increases.

A target vehicle speed is switched between a target slip vehicle speed and a target torque vehicle speed on the basis of a result of a determination regarding whether or not a vehicle is insufficiently accelerated. More specifically, if traction control is not performed, the target slip vehicle speed is set as the target vehicle speed. If it is determined that the vehicle is sufficiently accelerated during traction control, a value obtained by subtracting a maximum permissible value from a value set last time as the target vehicle speed is compared with the target slip vehicle speed, and the larger one of them is set as the target vehicle speed this time. If it is determined that the vehicle is insufficiently accelerated during traction control, the larger one of the target slip vehicle speed and the target torque vehicle speed is compared with a value obtained by adding a maximum permissible value to a value set last time as the target vehicle speed, and the smaller one of them is set as the target vehicle speed this time.

Traction control device

A rolling motion stability control apparatus restrains a roll increasing tendency of a vehicle, with each wheel of the vehicle being braked by a wheel brake device. A first braking force control device is provided for applying a first braking force to the wheel, when the vehicle is turned to one direction. A second braking force control device is provided for applying a second braking force to the wheel, when the vehicle is turned to the other direction. A terminating control adjustment device is provided for adjusting the braking force control devices to continue the first braking force being applied, until the second braking force is initiated to be applied, when the vehicle is turned to the one direction, and then to the other direction.

This device sets, upon executing only a roll-over preventing control, roll-over preventing braking force exerted on a front wheel at the outer side of the turning direction based upon a table value obtained through an absolute value |Gy| of an actual lateral acceleration and a predetermined table, and sets, upon executing only an US restraining control, US restraining braking force exerted on a rear wheel at the inner side of the turning direction based upon a table value obtained through an absolute value |&#x394;Gy| of a lateral acceleration deviation, that is a deviation between a target lateral acceleration and the actual lateral acceleration, and a predetermined table. In case where the roll-over preventing control and the US restraining control are simultaneously executed, the roll-over preventing braking force is similarly set and the US restraining braking force is set based upon a value obtained by multiplying the value based upon the table value by a predetermined US restraining braking force damping factor &#x3b1; (0&#x2266;&#x3b1;&#x2266;1), thereby giving priority to the roll-over preventing control.

A first state variable indicative of a rolling motion of a vehicle and a second state variable indicative of a different rolling motion of the vehicle from the first state variable are acquired. A roll increasing tendency of the vehicle is estimated on the basis of a characteristic including the second state variable. At least one of a braking force control and a driving force control is performed to restrain the roll increasing tendency of the vehicle, on the basis of the first state variable acquired when the roll increasing tendency is estimated.

The present invention is directed to a vehicle motion control apparatus, which includes a hydraulic pressure regulating device disposed between a master cylinder and a pair of wheel brake cylinders included in each of a dual hydraulic circuit, and a monitor for monitoring state variable of the vehicle. It is determined whether a wheel out of the wheels operatively associated with the pair of wheel brake cylinders is located on the inside of a curve along which the vehicle is turning, or located on the outside of the curve. Also, a state of road holding of the wheel located on the inside of the curve is determined. A desired value for the wheel located on the outside of the curve is set at least on the basis of the road holding determination. And, the pressure regulating device is controlled in response to a result of comparison between the desired value and the monitored state variable, to regulate the hydraulic braking pressure in the wheel brake cylinder operatively associated with the wheel located on the outside of the curve, whereby the vehicle is decelerated smoothly, when the wheel located on the inside of the curve has come to be apart from the road.

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Kariya, Japan

Junya Nagaya