Jtekt Corporation

Koyo Seiko Company, Ltd.

Other

Ryouhei Hayama

Tomoyasu Kada

Shingo Maeda

Shiro Nakano

Masaya Segawa

Katsutoshi Nishizaki

Shirou Nakano

Kenji Higashi

Shuuji Kimura

Naotake Kanda

Masayasu Higashi

Takanobu Takamatsu

Kazuhiro Kato

Takeo Iino

Masaharu Tagami

Sadahiro Kawahara

Aris Maroonian

Kou Shiba

Masayuki Ueno

Takeshi Watanabe

Kazushi Numazaki

Masami Naka

Masanori Arima

Hiroshi Yoshimoto

Akihiro Takazato

Hideyuki Mukae

Shoji Koyama

Sachio Yoshida

A steering system is provided which more appropriately alleviates driver's discomfort in the wrists. A steering ECU has an estimated grip angle calculating circuit, a deviation calculating circuit, an automatic steering torque command value calculating circuit, and a grip angle command value calculating circuit. The estimated grip angle calculating circuit calculates an estimated grip angle based on a steering angle. The deviation calculating circuit calculates a deviation based on the steering angle, a steering angle deviation, and the estimated grip angle. The grip angle command value calculating circuit calculates a grip angle command value that is a sum of a grip angle and the deviation.

Steering system

A test system includes an actual machine including a test piece that is a mechanical element of a vehicle, the actual machine being installed in a first location; a control device that is installed in the first location, and controls the actual machine; a model installed in a second location away from the first location; and a data processor that is installed in the second location, and is connected to the actual machine or the control device via a communication line so that data communication is performed, the data processor acquiring data from the actual machine via the communication line so that an operation test is performed. The data processor calculates a target value for controlling the actual machine based on an output acquired by inputting the acquired data to the model, and the control device controls the actual machine based on the target value.

Test system

A vehicle test apparatus includes: a test article installation vehicle body to which four axles corresponding to four wheels that are a left front wheel, a right front wheel, a left rear wheel and a right rear wheel are attached, and on which a test article is installed; a first motion base that supports the test article installation vehicle body, and that allows the test article installation vehicle body to make motions of six degrees of freedom; and four second motion bases each of which supports a corresponding one of the axles, and each of which allows a corresponding one of the axles to make motions of six degrees of freedom.

Vehicle test apparatus and vehicle test system

In a vehicle steering system configured to reduce the burden placed on an operator when steered wheels are returned to a neutral position, a knob for operating a steering wheel is turnably attached to the steering wheel. A switch is attached to the knob. A steered system ECU includes a target steered angle setting unit. The target steered angle setting unit changes a target steered angle to a steered angle corresponding to a position closer to the neutral position of the steered wheels when the switch is turned on in a state where the turning amount of the steering wheel from a turning angle of the steering wheel corresponding to the neutral position of the steered wheels is within a prescribed range.

Vehicle steering system

A vehicle steering system, in which a steering member and steered wheels are not mechanically coupled to each other, includes a rotation angle restriction mechanism that restricts a rotation angle of the steering member within a restricted angular range. In a failure mode, that is, in a case where a malfunction occurs in a steering angle sensor, a steering direction is detected on the basis of a strain of the rotation angle restriction mechanism, which is detected by one of strain gauges at a corresponding one of a pair of terminal ends of a restricted angular range. Drive control is executed on a steered system actuator on the basis of the detected steering direction.

A motor vehicle steering system includes a knob for rotationally manipulating a steering member and a knob reaction force actuator for giving a reaction force in response to the rotation of the knob. The knob has a knob center and is supported by the steering member in a manner rotatable about the knob center. Holding the knob and manipulating the steering member causes the knob to rotate (spin) about the knob center as the steering member rotates. The knob reaction force actuator then gives an appropriate reaction force in response to the rotation (spinning) of the knob.

Motor vehicle steering system

When a partial malfunction is detected, a sensor malfunction determination unit changes a control mode from a first control mode to a second control mode. When the control mode is changed from the first control mode to the second control mode, a steered system motor is rotated in a direction corresponding to a rotation direction of a steering wheel immediately before the partial malfunction occurs in the angle sensor. When the absolute value of a steering angular velocity of the steering wheel exceeds a threshold, it is determined that a driver has operated the steering wheel in a direction opposite to a current steered direction, and the rotation direction of the steered system motor is reversed.

In a vehicle steering system, when a sensor malfunction determination unit detects a malfunction of a rotation angle sensor, the sensor malfunction determination unit changes a control mode from a first control mode to a second control mode. In the second control mode, an actual rotor angle (mechanical angle) (&#x3b8;) of a steered system motor is computed on the basis of a second rotor angle (electric angle) (&#x3b8;) estimated by a rotation angle estimation unit. Then, feedback control is executed such that the actual rotor angle (&#x3b8;) converges to a target rotor angle (&#x3b8;*) that is obtained by superimposing a rotation maintaining command signal on a target rotor angle (&#x3b8;*) computed by a target rotor angle computation unit.

In a material handling vehicle such as an electric forklift, a depression amount of an accelerator pedal that provides an instruction on a control amount of a drive motor for driving a drive wheel is detected. When the depression amount of the accelerator pedal is equal to or larger than a predetermined value and a forward-backward switching signal that indicates that a shift lever is operated is received, a drive current for a steered system motor is set to a value smaller than a normal drive current within a predetermined time period that starts upon reception of the forward-backward switching signal.

Control apparatus for steering mechanism

A steering angle detecting unit, a reaction force actuator that applies steering reaction force to a steering member, a yaw angle detecting unit that detects a yaw angle of a vehicle body, and a reaction force actuator control unit that sets the steering reaction force as a function of a steering angle and that controls the reaction force actuator such that the reaction force actuator generates the set steering reaction force, are provided. The reaction force actuator control unit computes a turning angle of the vehicle body on the basis of a change in the yaw angle of the vehicle body, detected by the yaw angle detecting unit. When the computed turning angle is larger than or equal to a reference angle, the steering reaction force applied to the steering member is increased.

Vehicle steering system and material handling vehicle

A vehicle steering apparatus in which a mechanical coupling between a steering member and steered wheels is uncoupled, includes a steering actuator for driving a steered mechanism and a control unit for drive-controlling the steering actuator. The control unit reduces steering-stiffness using a PID control portion for drive-controlling the steering actuator according to a deviation between a target steered angle and a steered-angle detected by the steered angle sensor. A gain setting portion sets gains of the PID control portion to be relatively low when a predetermined condition is satisfied.

Vehicle steering apparatus

A motor vehicle steering system steers vehicle wheels in response to the operation of an operation member for steering a vehicle. The system includes a rutted road judging unit which judges whether the vehicle is driving on a rutted road or not, and a steering enhancement control unit which enhances steering of vehicle wheels in response to operation of the operation member when the rutted road judging unit judges that the vehicle is driving on a rutted road than when the rutted road judging unit judges that the vehicle is not driving on a rutted road.

A motor vehicle steering system includes a knob that is for rotating a wheel of a steering member, has a knob center, and is supported rotatably around the knob center by the wheel. A control unit sets a predetermined period after detection of gripping on the knob by a grip detection device as a transfer period for transfer from reaction force application only by a wheel reaction force actuator to reaction force application only by a knob reaction force actuator. In the transfer period, the knob reaction force is increased with time and the wheel reaction force is reduced with time.

A steered shaft of a steered mechanism is rigidly fixed to a vehicle body. Steering-stiffness is reduced by a lowpass filter for filtering a steered angle detected by a steered angle sensor. A deviation between a target steered angle and the filtered steered angle detected by the steered angle sensor is input to a PID control unit. A gain setting unit sets each of gains for PID control at a low value to thereby reduce steering-stiffness. The PID control unit outputs a target current. A drive circuit performs, e.g., PID control of the steering actuator.

A vehicle steering device () has a steering actuator () for steerable wheels () to be steered according to operation of a steering member (), a transmission mechanism () including cables (), a connection mechanism () for allowing and interrupting mechanical connection between the steering member () and the wheels (), and control unit (). When the steering actuator () is normal, the control unit () causes the connection mechanism () to release mechanical connection between the steering member () and the wheels () and drives and controls the steering actuator () according to operation of the steering member (). The control unit () includes a fail detecting section () for detecting, when the steering actuator () is normal, a fail of the transmission mechanism () based on a load on the steering actuator ().

Growing community of inventors

Nabari, Japan

Ryouhei Hayama