Jtekt Corporation

Toyota Jidosha Kabushiki Kaisha

Robert Fuchs

Tsutomu Tamura

Naoki Shoji

Maxime Moreillon

Tomohiro Nakade

Mitsuko Yoshida

Frederic Wilhelm

Yasuhiko Hasuda

Takahiro Kojo

Yoji Kunihiro

Hisaya Akatsuka

Masayasu Higashi

Takahiko Kuwabara

Aris Maroonian

Yuta Sakai

Daisuke Miki

Philippe Mullhaupt

A motor control unit includes: an assist torque command value generation unit that generates an assist torque command value using steering torque; a manual steering command value generation unit that generates a manual steering command value using the steering torque and the assist torque command value; an integrated angle command value calculation unit that calculates an integrated angle command value by adding the manual steering command value to an automatic steering command value; and a switching unit that switches between a first control for controlling an electric motor based on the assist torque command value and a second control for controlling the electric motor based on the integrated angle command value, based on a switching signal.

Motor control device

A steering system includes a control unit. The control unit includes a manual steering angle command value setting unit, a first weighting unit, a reaction combined angle command value calculating unit, a turning combined angle command value calculating unit, a reaction force control unit configured to cause a rotation angle of a reaction motor to conform to a reaction combined angle command value, and a turning angle control unit configured to cause a rotation angle of a turning motor to conform to a turning combined angle command value.

Steering system

A vehicle steering device includes a first setting portionthat sets a target assist torque in accordance with a steering torque, a second setting portionthat sets an angle controlling target torque for bringing an angular deviation between a target steering angle and an actual steering angle close to zero, an estimator that estimates a compensation objectload with respect to the angle controlling target torque, a first calculating portionthat calculates a target automatic steering torque based on the angle controlling target torque set by the second setting portion and the compensation object load estimated by the estimator, and a second calculating portionthat performs weighted addition of the target automatic steering torque and the target assist torque in accordance with a value that changes in accordance with a driver input to calculate a target motor torque that is a target value of a motor torque of the electric motor.

Vehicle steering device

A steering device includes a steering member, a steering operation mechanism, a reactive force motor, a steering motor that drives the steering operation mechanism, a steering torque sensor, and an electronic control unit. The electronic control unit sets a manual steering angle command value. The electronic control unit computes a reactive-force-related composite angle command value. The electronic control unit computes a steering-related composite angle command value based on a steering-related automatic steering angle command value and the manual steering angle command value. The electronic control unit causes a rotational angle of the reactive force motor to follow the reactive-force-related composite angle command value. The electronic control unit causes a rotational angle of the steering motor to follow the steering-related composite angle command value. The electronic control unit estimates a first disturbance torque.

Steering device

A vehicle steering device includes an electric motor applying a steering force to a vehicle turning mechanism, a first setting portion setting a target assist torque in accordance with a steering torque, a second setting portion setting an angle controlling target torque for bringing an angular deviation between a target steering angle and an actual steering angle close to zero, a restriction processing portion restricting the angle controlling target torque set by the second setting portion, a first calculating portion calculating a target automatic steering torque using the angle controlling target torque after the restriction process by the restriction processing portion, and second calculating portions performing weighted addition of the target automatic steering torque and the target assist torque in accordance with a value that changes in accordance with a driver input to calculate a target motor torque that is a electric motor target motor torque value.

A motor controlling ECUincludes an automatic steering controllerthat sets an automatic steering control amount, an assist controllerthat sets an assist control amount, an integrated control amount calculating portionthat calculates an integrated control amount by adding the automatic steering control amount and the assist control amount, and an actual automatic steering angle calculating portionthat calculates, based on at least one of either of a steering torque and the assist control amount, an actual automatic steering angle that is a steering angle due to automatic steering control and included in an actual steering angle. The automatic steering controlleruses a target automatic steering angle and the actual automatic steering angle to set the automatic steering control amount.

A steering determination device determines a steering state in which a driver of a vehicle is steering a steering wheel of the vehicle. The device includes a torque recognition unit configured to recognize a steering torque based on a measurement result of a torque sensor provided on a steering shaft, an acceleration recognition unit configured to recognize longitudinal acceleration or lateral acceleration, a threshold value setting unit configured to set a threshold value for the determination of the steering state, based on the longitudinal acceleration or the lateral acceleration, and a steering determination unit configured to determine that the driver is in the steering state if the steering torque is equal to or greater than the threshold value. The threshold value setting unit is configured to set the threshold value such that the threshold value decreases as an absolute value of the longitudinal acceleration or the lateral acceleration decreases.

Steering determination device and autonomous driving system

An electric power steering system includes an electric motor, a rotational angle detection unit, a current detection circuit, a steering torque detection unit, a target torque setting unit, a current command value setting unit, and a current control unit. The target torque setting unit includes a basic target torque setting unit, a first compensation value computation unit, a second compensation value computation unit, and a correction unit. The basic target torque setting unit sets basic target torque for the electric motor. The first compensation value computation unit sets a first compensation value based on steering torque. The second compensation value computation unit computes a second compensation value which is an estimated value of disturbance torque other than the steering torque. The correction unit corrects the basic target torque.

Electric power steering system

Provided is a steering system including a controller that controls an electric motor. The controller has a combined friction torque estimation unit that estimates a combined friction torque combining friction torques occurring in respective transmission devices including a first transmission device. The combined friction torque estimation unit has a slipping speed calculation part that calculates a slipping speed of the first transmission device based on an angular speed of the electric motor, a friction coefficient calculation part that calculates a friction coefficient of the first transmission device based on the slipping speed, a tooth flank normal force calculation part that calculates a normal force acting on a tooth flank of the first transmission device, and a friction torque calculation part that calculates the combined friction torque using the friction coefficient, the tooth flank normal force, and one or more preset correction factors.

A steering system includes: a steering member; a steering operation mechanism; a reaction force motor; a steering motor; a steering torque sensor; a command value setting circuit; a reaction force command value calculation circuit configured to calculate a reaction force command value; a steering operation command value calculation circuit configured to calculate a steering operation command value based on a steering operation steering angle command value and a manual steering angle command value; a reaction force control circuit configured to cause a rotation angle of the reaction force motor to follow the reaction force command value; and a steered angle control circuit configured to cause a rotation angle of the steering motor to follow the steering operation command value.

A steering system includes an electric motor, a detector, and a controller of a vehicle. The controller is configured to control the electric motor by switching an autonomous steering mode, a manual steering mode, and a cooperative steering mode. The controller is configured to control the electric motor in the cooperative steering mode unconditionally or when a predetermined condition is satisfied in a case where a situation to switch a steering mode to the manual steering mode during control in the autonomous steering mode is predicted and a manual steering request is transmitted at a time point that is prior, by a first predetermined time, to occurrence of the situation, or is transmitted when the vehicle arrives at a point that is located a first predetermined distance before a point where the situation is to occur.

An electric power steering system includes a second shaft coupled to a first shaft via a torsion bar, a basic driver torque estimation unit (extended state observer) configured to estimate a basic driver torque by using a disturbance observer based on a torsion bar torque and a rotation angle of the second shaft, a gravity torque calculation unit configured to calculate, by using a rotation angle of a steering wheel, a gravity torque applied to the first shaft by gravity acting on the center of gravity of the steering wheel, and a driver torque estimation unit configured to estimate a driver torque by using the basic driver torque estimated by the basic driver torque estimation unit and the gravity torque calculated by the gravity torque calculation unit.

Driver torque estimation apparatus and steering system including the same

A manual steering command value generation unit generates a manual steering command value using steering torque. An integrated angle command value computation unit computes an integrated angle command value by adding the manual steering command value to an automatic steering command value. A control unit performs angle control on an electric motor on the basis of the integrated angle command value. The control unit includes: a basic torque command value computation unit that computes a basic torque command value on the basis of the integrated angle command value; a disturbance torque estimation unit that estimates disturbance torque other than motor torque that is generated by the electric motor and acts on an object to be driven by the electric motor; and a disturbance torque compensation unit that corrects the basic torque command value in accordance with the disturbance torque.

A steering device includes a steering wheel, a torsion bar, a spiral cable, a torque sensor, and an electronic control unit. The electronic control unit is configured to compute a rotational angle of the steering wheel. The electronic control unit is configured to compute, as driver torque, a value that includes a sum obtained by adding torsion bar torque, a steering wheel inertial torque compensation value and a spiral cable torque compensation value. The steering wheel inertial torque compensation value is the product of a steering wheel inertial moment and a second-order differential value of the rotational angle of the steering wheel. The spiral cable torque is torque that acts on the steering wheel because of the spiral cable.

A steering apparatus includes: a first shaft which is coupled to a steering wheel; a torsion bar; a second shaft which is coupled to the first shaft through the torsion bar; a torsion bar torque detection unit detecting a torsion bar torque which is applied to the torsion bar; and an electronic control unit configured to estimate a driver torque which is applied to the steering wheel by a driver. The electronic control unit is configured to: i) compute a steering wheel rotation angle which is a rotation angle of the steering wheel; and ii) compute a value including an added value, as the driver torque, the added value being a value resulting from adding the torsion bar torque, a steering wheel inertia torque compensation value, and a gravity torque compensation value.

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Nara, Japan

Robert Fuchs