Jtekt Corporation

Toyota Jidosha Kabushiki Kaisha

Denso Corporation

Naoki Yamano

Hidenori Itamoto

Takashi Kodera

Koji Anraku

Yoshihiro Yamashita

Satoru Mikamo

Hiroshi Suzuki

Terutaka Tamaizumi

Hideki Kabune

Kenichiro Aoki

Akira Nambu

Akira Yamamoto

Yuko Onoda

The steer-by-wire steering system comprise a steering input device and a steering operation device that steers wheels which are mechanically coupleable. The steering input device includes a steering-side motor that supplies a steering shaft with a steering reaction force, the steering operation device includes a steered-side motor that supplies a rack shaft with a steering force, and a power supply control circuit that controls the steering-side motor to generate the steering reaction force and that controls the steered-side motor to generate the steering force. When the duty ratio of a duty signal that is generated to control the power supply to the steered-side motor reaches a setting value that is defined to indicate that a steered angle becomes unable to follow a steering angle, the power supply control circuit controls the power supply to the steering-side motor such that the steering-side motor increases the steering reaction force.

Steer-by-wire steering system

There is provided a steering control device that can control even when a systematic error has occurred. An update amount calculation processing circuit manipulates a control angle in accordance with an update amount in order to control steering torque, which is obtained by subjecting the magnitude of steering torque to a decrease correction by a threshold, to target torque through feedback control. The control angle is used to convert a current command value to a value in a fixed coordinate system or the like. The update amount is subjected to a guarding process in accordance with the steering torque by a torque-based guarding processing circuit, and determined as a final update amount for the control angle. The torque-based guarding processing circuit performs the guarding process on the update amount such that the update amount is in an allowable range that matches the steering torque.

Steering control device

A steering control apparatus is provided which suppresses possible vibration of a steering system resulting from differential steering processing when a steering angle or a steered angle has a large value. A differential steering processing circuit calculates a differential steering correction amount based on a difference value of a target steering angle, and increases or reduces the target steering angle using the calculated amount to obtain a target steered angle. A limiting reaction force setting processing circuit increases a limiting reaction force when a maximum value of the target steering angle and the target steered angle is equal to or larger than a common threshold. When the maximum value approaches the common threshold, an angle-sensitive gain setting processing circuit reduces an angle-sensitive gain so as to correct and reduce the differential steering correction amount.

Steering control apparatus

An update amount calculation processing circuit manipulates a control angle based on an update amount in order to perform feedback-control for causing a steering torque to be adjusted to a target torque. In this case, the update amount calculation processing circuit executes a guard process on the update amount with reference to an estimated amount of change that is a speed equivalent value based on estimation by an induced voltage observer. However, when a command current set by a command current setting processing circuit is zero, the update amount calculation processing circuit determines the estimated amount of change subjected to the guard process to be the update amount. When the command current is zero and the update amount is fixed to a guard value, an electric path between the synchronous motor and a battery is blocked.

A steering control apparatus includes a steering angle feedback processing unit and an operation signal generation processing unit that operate a reaction force actuator to adjust a steering angle to a target steering angle that is a target value for the steering angle based on feedback control, an ideal-axial-force calculation unit that calculates an ideal axial force, a road-surface-axial-force calculation unit that calculates a road surface axial force, an axial-force allocation calculation unit that calculates a base reaction force in which the ideal axial force and the road surface axial force are allocated in a predetermined ratio, and a target steering angle calculation processing unit that sets a target steering angle based on the base reaction force. The steering angle feedback processing unit feeds back the target steering angle in which road surface information is incorporated through the road surface axial force, so that the steering angle is controlled.

A sensor device, such as a torque sensor, of a motor control device or an electric power steering apparatus includes a sensor section that detects a quantity of state of a detection subject and outputs a detection signal corresponding to the detected quantity of state. When receiving a specific trigger transmitted from an external device, the sensor section outputs an abnormality diagnosis signal, which is configured by a predetermined waveform and used for determining whether there is an output abnormality of the sensor section, and then outputs the detection signal.

Sensor device, motor control device, and electric power steering apparatus

A steering control system for a vehicle includes an electric motor, a torque sensor, an angular velocity sensor, and a control unit. The electric motor applies assist force to a turning operation of a steering wheel. The torque sensor detects a torque generated in a steering system including the steering wheel and varying with the turning operation. The angular velocity sensor detects an angular velocity generated in the steering system and varying with the turning operation. The control unit computes an assist control amount for the turning operation by using the torque and the angular velocity, and, when an abnormality occurs in a torque detection operation, increases a control amount computed by using the angular velocity among control amounts that constitute the assist control amount as compared to that when torque sensor operation is normal and executes drive control over the electric motor based on the assist control amount.

Steering control system for vehicle and steering control method for vehicle

A motor control signal output unit of an electric power steering system includes a feedback gain calculation unit (), and a feedback control unit executes a feedback control with the use of a proportional gain (Kp) and an integral gain (Ki) that are calculated by the feedback gain calculation unit (). The feedback gain calculation unit () sets the feedback gains to large values (Kp=P, Ki=I) when the absolute value of an assist gradient (&#x3b1;) is equal to or smaller than a predetermined value (&#x3b1;) (|&#x3b1;|&#x2266;&#x3b1;). On the other hand, when the absolute value of the assist gradient (&#x3b1;) exceeds the predetermined value (&#x3b1;) (|&#x3b1;|&#x3e;&#x3b1;), the feedback gain calculation unit () sets the feedback gains to small values (Kp=p, Ki=I:P&#x3c;P, I&#x3c;I).

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Okazaki, Japan

Naoki Yamano