Toyota Jidosha Kabushiki Kaisha

Other

Yutaka Onuma

Hiroshi Isono

Yasuji Mizutani

Takeshi Goto

Motoshi Suzuki

Hirofumi Nitta

Yuichi Onoda

Koichi Kondo

Ryuuichi Kurosawa

An electronic control unit receives a detection value from each sensor, and determines a familiarity degree coefficient indicating the degree of driver's familiarity with steering characteristics, using the received detection values. When the coefficient has a value near '0', a desired actual steering angle is calculated to be a small value, and when the coefficient has a value near '1', a desired actual steering angle is calculated to be a large value. When the coefficient has a value near &#x201c;0&#x201d;, a time constant of an actual steering actuator is set to a large value, and when the coefficient has a value near &#x201c;1&#x201d;, the time constant is set to a small value. A reaction torque is determined based on the coefficient.

Vehicle steering system and method of controlling the same

A steering-by-wire-type steering apparatus for a vehicle which can detect an anomaly of a connecting-disconnecting device which selectively connects and disconnects an input member on a steering wheel side and an output member on a turnable wheel side based on a steering input operation quantity or a steering state quantity.

Steering apparatus for vehicle that detects an anomaly of the connecting-disconnecting device between the steering wheel and the turnable wheels

A steering system including a pair of operating members operable independently of each other, wherein a target wheel-turning amount and a return force for returning operating members to their reference position are determined based on an operation amount of the operating members. At least either a steering gain, set for each pair of operating members upon determination of the target wheel-turning amount, or a return-force gain, set for each pair of operating members upon determination of the return force, is made changeable depending on various parameters. Steering characteristics can be set relatively freely. For example, where the steering gain is made changeable depending on an operating angle of the operating member, determination of the target wheel-turning amount can be made with a changeable degree of contribution of operation of each operating member, which is changeable depending on an operating position of the operating member.

Steering system for vehicle

An electronic control unit inputs a side slip angle &#x3b2; of a vehicle body. The unit calculates a dynamic zero point &#x3b4;o for reducing a lateral force generated in the vehicle due to the side slip angle &#x3b2; of the vehicle body. The unit calculates a steering angle &#x3b4;a, which is represented by the difference between the dynamic zero point &#x3b4;o and a steering angle &#x3b4; detected by a steering angle sensor. The unit calculates a reaction torque Tz having a predetermined relation with the steering angle &#x3b4;a. The unit drives and controls an electric motor to generate the calculated reaction torque Tz. Thus, the unit guides a driver to a proper steering-wheel rotating direction.

Steering apparatus for vehicle

Vehicle braking system including a vacuum booster for transmitting a boosted brake operating force to a master cylinder such that the boosting ratio is reduced at a fixed transition point before the boosting limit point is reached, a brake having a wheel brake cylinder connected through a fluid passage to a master cylinder serving as a first hydraulic pressure source, for braking a wheel, and a pressure increasing device having a second hydraulic pressure source connected to the fluid passage, and wherein the pressure increasing device initiating a pressure increasing operation, when the brake operating force has increased to the transition point, to increase the wheel cylinder pressure to be higher than the master cylinder pressure, by using the second hydraulic pressure source.

Braking system having vacuum booster whose boosting ratio is lowered at fixed transition point at which wheel cylinder pressure increase is initiated

In controlling the operation of a powered brake system of a vehicle in which wheel cylinders of the brake system are supplied with brake fluid compressed by a motor powered pump under a control of an electric controller according to a stroke of depression of a brake pedal by a driver detected by a brake depression stroke sensor and a master cylinder pressure generated by the brake depression detected by a master cylinder pressure sensor, a brake control device makes a double checking if the depression stroke detected by the sensor exceeds a predetermined threshold value, and also if the brake pedal is depressed at least for a predetermined stroke detectable by a stroke limit switch, before starting the operation of the powered brake system. When the stroke limit switch has failed, instead, the brake control device checks if the master cylinder pressure increases to a predetermined value to start the operation of the powered brake system with an initial biasing reduction of the starting brake force.

Brake control device of vehicle operable with double checking of driver's positive braking intention

In a device for judging a normal operation of a brake system of a vehicle such as an automobile by judging if the stroke of the brake pedal depression detected by a stroke sensor and the master cylinder pressure detected by a pressure sensor are correlated with one another within a range determined for a judgment of a normal operation of the brake system, the device detects speed of change of at least one of the stroke and the pressure, and refrains from executing the judgment when at least one of the stroke change speed and the pressure change speed is not smaller than a threshold value determined therefor.

Growing community of inventors

Nishikamo-gun, Japan

Yutaka Onuma