Abstract: In a steer-by-wire steering system for a vehicle, a control unit (16) controls an operation of a steering actuator to cause the steered angle of wheels to be in a prescribed relationship to a steering angle, and an operation of the reaction force actuator (15) including a pair of reaction force motors (14) to cause the reaction force to be a value (Tt) corresponding to a steered state of the wheels, wherein the control unit is provided with a failure detection unit (36) configured to detect failures of the reaction force motors, and upon detecting a failure of one of the reaction force motors, progressively reduce an output (Tta) of the other reaction motor to a prescribed limit value (TL).

Abstract: Provided is a steer-by-wire steering system (1) for a vehicle (2) that can appropriately bring the steered angle of the wheels to a prescribed relationship to the steering angle of a steering member (10) even when the steering angle of the steering member was changed while the vehicle was parked. When the steered angle of the wheels deviates from the prescribed relationship with the steering angle of the steering member upon startup (ST2: Yes), the control unit (15) drives at least one of the steering actuator (12) and the reaction force actuator (13) to bring the steered angle (?) of the wheels closer to the prescribed relationship with the steering angle (?) of the steering member (ST12) using a change in the transmission shift position from the park position (P) or the neutral position (N) to the travel position (D or R) as a trigger (ST8: Yes).

Abstract: A steer-by-wire steering system for a motor vehicle or a steering system for an autonomous driving motor vehicle includes a controller configured or programmed to control steering of steerable road wheels depending on a driver's input or an input of an autonomous driving unit and to include a normal mode of operation with full steering functionality and no quality problems, and at least two degraded modes with degraded operation of the steering system. The steering system includes an evaluator to evaluate a state of performance degradation of the steering system and to set the operation mode of the controller based on an evaluation result from the evaluator.

Abstract: A steer-by-wire steering system including a feedback actuator to simulate a steering feel to a steering device and including an electric motor connected to a steering shaft to transmit a torque, and a steering lock including a latch connected to the steering shaft in a torsion-resistant manner and a lock to engage with the latch at locking positions to block a rotation of the steering shaft. If an ignition is switched-off and a movement of the steering device is detected, a position of the steering shaft and a distance between the lock and a next locking position of the latch is determined. If the distance is greater than a predefined value, a counter-torque is transmitted to the steering shaft by the feedback-actuator opposite to the movement of the steering device until the locking position reaches the lock and the lock can engage with the latch.

Abstract: A method to control a steer-by-wire steering system for a road vehicle, the steer-by-wire steering system including a steering wheel, a road wheel actuator to actuate road wheels, and a feedback actuator to apply a feedback torque to the steering wheel, the method including, if an ingress situation is detected, switching on the feedback actuator and providing a resistance torque against rotation of the steering wheel in an ingress mode, and if a normal steering system shut down procedure is finished, activating an egress mode of the feedback actuator and providing a resistance torque against rotation of the steering wheel.

Abstract: A method to control a steering system of a road vehicle, the steering system including an actuator with at least two redundant power packs, the method including detecting a failure and/or degradation in or of the at least two redundant power packs of the actuator and/or switching off a malfunctioning one of the at least two redundant power packs, or detecting extreme loads or short-term performance requirements; and increasing a supply voltage for at least one functioning power pack of the actuator to a value higher than a supply voltage under normal conditions to provide a higher power output of the actuator than power output under normal conditions.

Abstract: Provided is a steering system for a vehicle that can accurately determine a degradation level of a steering actuator according to a traveling state of the vehicle. The steering system for the vehicle includes; a steering mechanism configured to steer wheels; a steering actuator configured to apply a driving force to the steering mechanism; and a controller configured to control the steering actuator. The steering mechanism includes a rack shaft that is movable in a vehicle width direction from a prescribed reference position. The controller is configured to calculate an evaluation value according to a use state of the steering actuator and to determine a degradation level of the steering actuator by comparing the evaluation value with at least one threshold that is set based on a moving amount of the rack shaft from the reference position and a vehicle speed.

Abstract: A method to control a steering system or a sub-system of a road vehicle including a controller to operate in a normal mode with full steering functionality and no quality problems and at least two degraded operation modes with degraded operation of the steering system, the controller including an evaluator including an allocation between degradation levels of the steering system or the sub-system and operation modes, and the method includes determining an overall degradation level for the steering system or the sub-system by collecting single individual degradation levels of the steering system or the sub-system in the evaluator and determining an overall degradation level as a level with a highest degradation of the single individual degradation levels which in a corresponding operation mode provides enough performance of the steering system for an expected maximum power request.

Abstract: A steer-by-wire steering system for a road vehicle includes a road wheel actuator to act on steerable wheels and electronically controlled as a function of a driver's steering request, a feedback actuator to transmit reactions of a road to a steering wheel, and a single steering wheel angle sensor to measure a steering wheel angle. The steering wheel angle sensor is an external sensor able to communicate on a second vehicle communication channel or via a private communication with the road wheel actuator. The steer-by-wire steering system also includes an external road wheel actuator position sensor to measure a position of the road wheel actuator and to communicate on the second vehicle communication channel or via the private communication with the road wheel actuator.

Abstract: A method of controlling a steering system for a vehicle includes determining a state of performance degradation of the steering system, determining a vehicle situation, determining if a performance of the steering system in the determined state of performance degradation is sufficient for the determined vehicle situation, and, if the performance of the steering system is not sufficient, modifying the state of performance degradation by decreasing a degradation level for a period of time.

Abstract: A method to control a steer-by-wire steering system of a road vehicle, the steer-by-wire steering system including a feedback actuator to apply a feedback torque to a steering wheel and a road wheel actuator to turn steerable road wheels with two redundant power packs each, the method including, if a failure in the road wheel actuator is detected, increasing the feedback torque provided by the feedback actuator to a value higher than a calculated feedback torque, and if a failure in one power pack of the feedback actuator is detected, increasing the feedback torque provided by a functioning power pack of the feedback actuator to a value higher than the calculated feedback torque.

Abstract: A method to control a steering system of a motor vehicle, the steering system including at least one actuator with two redundant power packs each, the method including detecting a failure in or of one of the two redundant power packs of the at least one actuator and switching off a malfunctioning power pack, increasing a maximum output power of a functioning power pack of the at least one actuator to a value higher than a rated power for a defined period of time, and after the defined period of time, reducing the maximum output power of the functioning power pack of the at least one actuator back to the rated power or below.

Abstract: When the driving mode of a vehicle is switched from an automatic driving mode to a manual driving mode in response to steering of the steering wheel by a driver while the vehicle is traveling in the automatic driving mode, a control device determines whether a recognized steering angle which is the steering angle of the steering wheel recognized by the driver is near a neutral position or near a one turn position according to the grip positions on the steering wheel, and when the determined recognized steering angle differs from an actual steering angle, the control device changes a ratio between the steering angle of the steering wheel and a steered angle of a wheel such that the steered angle approaches a recognized steered angle corresponding to the recognized steering angle.

Abstract: A steering device includes: a steering wheel which is rotatable over an angle range exceeding 180 degrees in each of leftward and rightward directions from a neutral position; a steering mechanism that steers a wheel according to a steering angle of the steering wheel, with a ratio of the steering angle to a steered angle being changeable; and a control device that controls the ratio of the steering mechanism. The control device sets the ratio to a first value during travel of a vehicle in the manual driving mode and sets the ratio to a second value smaller than the first value during travel of the vehicle in the automatic driving mode, wherein the second value is set such that the steering angle corresponding to a maximum steered angle of the wheel specified by the steering mechanism is less than 180 degrees.

Abstract: A control device for a vehicle equipped with a steering system including a steering wheel (13), a rack (12) for steering the wheels (4) of the vehicle, and a redundant arrangement for transmitting a displacement of the steering wheel to the rack, wherein upon detecting a failure in the redundant arrangement, the control device sets an upper limit speed to a first value in a first stage, and changes the upper limit speed from the first value to a second value smaller than the first value in a progressive manner in a second stage that follows the first stage.

Abstract: A control device for a vehicle equipped with a steering system including a steering wheel (13), a rack (12) for steering the wheels (4) of the vehicle, and a redundant arrangement for transmitting a displacement of the steering wheel to the rack, wherein upon detecting a failure in the redundant arrangement, the control device sets an upper limit speed to a first value in a first stage, and changes the upper limit speed from the first value to a second value smaller than the first value in a progressive manner in a second stage that follows the first stage.

Abstract: Provided is a steer-by-wire steering system (1) for a vehicle (2) that can appropriately bring the steered angle of the wheels to a prescribed relationship to the steering angle of a steering member (10) even when the steering angle of the steering member was changed while the vehicle was parked. When the steered angle of the wheels deviates from the prescribed relationship with the steering angle of the steering member upon startup (ST2: Yes), the control unit (15) drives at least one of the steering actuator (12) and the reaction force actuator (13) to bring the steered angle (?) of the wheels closer to the prescribed relationship with the steering angle (?) of the steering member (ST12) using a change in the transmission shift position from the park position (P) or the neutral position (N) to the travel position (D or R) as a trigger (ST8: Yes).

Abstract: Provided is a steer-by-wire steering system for a vehicle that can reduce or eliminate the impact noise generated by the rack at the rack end. A control unit of the steering system is configured to determine a target steered angle (?t) according to the steering angle and drive the steering actuator so as to cause the steered angle to coincide with the target steered angle, and to determine a target reaction force (Tt) according to a steered state of the wheels and drive the reaction force actuator so as to cause the reaction force to coincide with the target reaction force. The control unit is further configured to set a maximum limit (?mC) on the target steered angle, the maximum limit being a value smaller than a physical maximum steered angle (?mP) of the wheels imposed by the steering mechanism.

Abstract: Provided is a steer-by-wire steering system for a vehicle that can prevent the vehicle from suddenly accelerating in a direction which the drive did not anticipate even when the steering angle of the steering member was changed while the vehicle was parked. When the steered angle deviates from the prescribed relationship to the steering angle (ST2: Yes), immediately or upon satisfaction of a trigger condition, the control unit drives the steering actuator to bring the steered angle to come closer to the prescribed relationship to the steering angle (ST16, ST17, ST20, ST21), and sets an upper limit to a speed or an acceleration of the vehicle (ST7).

Abstract: In a steer-by-wire steering system for a vehicle, a control unit (16) controls an operation of a steering actuator to cause the steered angle of wheels to be in a prescribed relationship to a steering angle, and an operation of the reaction force actuator (15) including a pair of reaction force motors (14) to cause the reaction force to be a value (Tt) corresponding to a steered state of the wheels, wherein the control unit is provided with a failure detection unit (36) configured to detect failures of the reaction force motors, and upon detecting a failure of one of the reaction force motors, progressively reduce an output (Tta) of the other reaction motor to a prescribed limit value (TL).