Advics Co., Ltd.

Toyoda Koki Kabushiki Kaisha

Aisin Seiki Kabushiki Kaisha

Jtekt Corporation

Other

Minekazu Momiyama

Hiroaki Kato

Yoshiyuki Yasui

Yuji Muragishi

Eiichi Ono

Kenji Asano

Wataru Tanaka

Hiroaki Aizawa

Katsuhiro Asano

Yuzo Imoto

Shinji Takeuchi

Hiroaki Niino

Takayuki Ohta

Tsuyoshi Murakami

Yuzou Imoto

Akihiro Ohno

Toshihiro Takahashi

Akira Kodama

Shoji Asai

Toshio Kohno

Shoji Ogawa

Hiroshi Kuroyanagi

Syoji Ogawa

A motor-driven steering controller for controlling a steering wheel of a vehicle. The controller includes a steering torque controlling unit, a braking force estimating unit, a right and left braking force difference estimating unit and an assist steering torque providing unit. The steering torque controlling unit controls a steering torque on the steering wheel depending on a steering operation. The braking force estimating unit estimates braking forces to be imposed on wheels of the vehicle. The right and left braking force difference estimating unit estimates difference between the braking forces to be imposed on the right and left wheels each estimated by the braking forces estimating unit. The assist steering torque providing unit provides an assist steering torque for the steering torque controlling unit on the basis of the difference in braking force between right and left wheels estimated by the right and left braking force difference estimating unit.

Motor-driven steering controller and automobile anti-skid controller

The control system of a vehicle controls the transmission ratio of the steering angle of a steering wheel relative to a turning angle of front wheels based on a drive force distribution ratio. Thus, the performance of the tires on the front wheels can be used to almost maximum potential, providing effective prevention of understeering.

Vehicle control system

A grip factor estimating apparatus includes a steering torque detecting unit M, and an assist torque detecting unit M. When a self-aligning torque estimating unit Mestimates self-aligning torque generated in front wheels on the basis of detection result of the detecting unit, the quantity of influence of longitudinal force on self-aligning torque is removed on the basis of longitudinal force acting on the front wheels and estimated by a longitudinal force estimating unit Mand a front wheel slip angle estimated by a front wheel slip angle estimating unit M. A grip factor estimating unit Mestimates the grip factor of the front wheels on the basis of change in self-aligning torque in accordance with the side force.

Wheel grip factor estimating apparatus and vehicle motion control apparatus

A steering control apparatus is provided for controlling a steered wheel angle of a wheel to be steered. On the basis of a road coefficient of friction estimated between right and left wheels, a braking force difference between the right and left wheels is calculated. A slip angle&#x2014;total lateral force characteristic indicative of a relationship between a slip angle and a total lateral force of a wheel to be steered is provided on the basis of the estimated coefficient of friction. Then, a steered wheel angle of the wheel to be steered is set on the basis of the braking force difference and the slip angle&#x2014;total lateral force characteristic.

Steering control apparatus for a vehicle

This invention provides a vehicle motion control method and a vehicle motion control apparatus capable of improving the behavior stability of a vehicle. According to the vehicle motion control method, vehicle steering characteristic is determined based on a behavior amount differentiated value obtained by differentiating (S) a slip angle differential value which is a behavior amount of the vehicle which occurs around a z-axis in the vertical direction with respect to the vehicle body (S, S). Consequently, because the phase of the slip angle differential value is progressed, the transition tendency of the steering characteristic, that is, which the vehicle motion condition is moved to over-steer or under-steer, can be obtained early. Therefore, the starting timing of the steering control or drive power control of the vehicle can be accelerated thereby improving the behavior stability of the vehicle.

Vehicle motion control method and vehicle motion control apparatus

A steering control apparatus obtains a steered amount by which a steered wheel is steered based on a left-and-right braking force difference control amount, a vehicle state control amount, and a steering control amount. The apparatus changes the magnitude of the braking force difference control amount and the magnitude of the vehicle state control amount according to a vehicle speed or to time elapsed from when braking started to be applied to the left and right wheels. Accordingly, the vehicle driving on a &#x3bc;-split road is prevented from being deflected toward a side of higher friction coefficient due to the left-and-right braking force difference when the braking is applied.

Steering control apparatus for vehicle and method for steering control

In a steering apparatus, in accordance with a grip limit control process ('), it is determined whether or not a grip degree &#x3b5; estimated by a grip degree estimation arithmetically operating process () is less than a predetermined grip degree (&#x3b5;&#x2032;), and in the case that it is determined that an estimated grip degree (&#x3b5;) is less than the predetermined grip degree (&#x3b5;&#x2032;), the process applies such a feeling that a steering operation by a steering wheel suddenly becomes light to a driver, by suddenly increasing an assist quantity by a motor (M), thereby notifying the driver of the matter that the grip degree of a steered wheel is close to a limit. Therefore, it is possible to transmit to the driver a probability that a side slip is generated by further turning the steering wheelin the same direction as the current direction, thereby calling the driver's attention for steering. Accordingly, there is an effect that a stability of a vehicle behavior can be improved without applying any fear of insecurity to the driver.

Steering device

In a steering system, a transmission ratio Rwhich is determined in dependence on the vehicle speed by reference to a transmission ratio decision map is multiplied with a first transmission ratio alteration gain gwhich is determined in dependence on the distribution of a traveling drive torque from an engineto front wheelsand rear wheels, thereby to alter the ratio Rof steering torque distribution from a steering handleto the front wheels, whereby the variation of the steering feeling due to an increase or decrease in the distribution of the traveling drive torque to the front wheelscan be suppressed. Further, the transmission ratio Ris multiplied with a second transmission ratio alteration gain gwhich is determined in dependence on the gradient of the road surface by reference to a second transmission ratio alteration map, thereby to alter the transmission ratio R, whereby the variation of the steering feeling due to the variation of the gradient can also be suppressed.

Steering system for vehicle

A vehicle motion control apparatus is provided with an anti-skid control device and a steering angle adjusting device, which adjusts the steering angle of at least one of the front and rear wheels to cancel a yaw deviation between a desired yaw factor and an actual yaw factor, to be substantially zero. An incompatibility between the devices is determined on the basis of a state of the wheel adjusted by the steering angle adjusting device to cancel the yaw deviation. And, a predetermined parameter provided between a vehicle stability directive parameter and a brake directive parameter is set on the basis of the incompatibility. Then, the anti-skid control device controls the braking force applied to each wheel of the vehicle on the basis of the predetermined parameter. Consequently, the anti-skid control giving importance to the braking force can be performed, as long as the steering angle adjusting device is operative.

Vehicle motion control apparatus

A vehicle motion control apparatus is provided for performing a vehicle stability control on the basis of a parameter indicative of lateral margin for a tire on a road. The apparatus includes a steering control device for controlling a relationship between a steering angle and a tire angle to be varied, and a decelerating control device for controlling a vehicle speed to be decreased. The parameter indicative of lateral margin for the tire is monitored, and the steering control device and the decelerating control device are controlled on the basis of the monitored parameter. The steering control device is controlled to decrease the tire angle relative to the steering angle, when the parameter is decreased from a value of relatively large lateral margin to a value of relatively small lateral margin, which is smaller than a first threshold value, and the decelerating control device is controlled to decrease the vehicle speed in addition to the steering control by the steering control device, when the parameter is further decreased to a value of lateral margin smaller than a second threshold value, which is smaller than the first threshold value.

An electronic control unit calculates a target yaw rate in accordance with a vehicle speed and a steering angle and calculates the yaw rate difference on the basis of the target yaw rate and an actual yaw rate. The electronic control unit estimates the grip factor of a front wheel to road surface and sets a distribution ratio for distribution of a vehicle-control target value among actuators of a steering system, a brake system, and a drive system in accordance with the estimated grip factor. The electronic control unit controls the actuators of the three systems in accordance with control instruction values distributed on the basis of the vehicle-control target value and the distribution ratio.

Integrated control apparatus for vehicle

In vehicle roll sensing of the present invention, a self-aligning torque (SAT) estimator estimates a composite value of SATs generated on tire contact patch of right and left wheels. A slip angle computer detects a vehicle speed and a steering angle and computes a slip angle of the wheel from the measured vehicle speed and steering angle. An SAT model value computer estimates an SAT model value as a composite value of SATs of the right and left wheels when no load shifts between the right and left wheels on the basis of the slip angle. A load shift ratio estimator estimates a load shift state of the right and left wheels on the basis of the composite value of the SATs of the wheels and the SAT model value. A vehicle rollover estimator estimates a rollover of the vehicle on the basis of the estimated load-shift state.

Vehicle roll sensing using load shift estimation

When a variable value indicates that a steering characteristic is understeer, a control unit controls a variable transmission ratio device to change a second steering angle such that the greater the understeer indicated by the variable value, the smaller the steering angle of steered wheels relative to the turning angle of a steering wheel becomes. When the differentiated value of the variable value indicates that the understeer is changing to increase, a correction unit corrects the variable value such that the greater the degree of change of the understeer indicated by the differentiated value, the greater the understeer indicated by the variable value becomes. Hence, the attitude of a vehicle in understeer is stabilized with a simple configuration.

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Chiryu, Japan

Minekazu Momiyama