A steering system includes a steering shaft; a motor configured to generate a torque applied to the steering shaft; and a control unit configured to control the motor. The control unit has a function of performing steering angle feedback control for causing a steering angle that is a rotation angle of a steering wheel to reach a target steering angle that is set based on a point of view of adjusting a rotational position of the steering wheel, as an adjustment process of adjusting the rotational position of the steering wheel. The control unit is configured to set a limit value for limiting a change range of the target steering angle with respect to the steering angle at each moment in a period in which automatic rotation of the steering wheel is hindered in a case where the automatic rotation is hindered while the adjustment process is being performed.

A differential cooperative active steering system for a front-axle independent-drive vehicle with electric wheels includes a steering rack which is arranged between a first steering wheel and a second steering wheel, and is able to generate lateral displacement and pull the first and second steering wheels to steer; a planetary gear mechanism, including a first input end, a second input end and an output end; a steering angle coupling motor, connected to the first input end; and an input shaft of the steering wheel, connected to the second input end. The planetary gear mechanism can realize the coupling between an input steering angle of an input shaft of the steering wheel and an input steering angle of the steering angle coupling motor. In addition, a method for controlling the differential cooperative active steering system is provided.

Disclosed herein are an apparatus and method of controlling a motor-driven power steering system. The apparatus may include: a sensor configured to detect at least one of a steering angle, an angular speed, and a column torque in the motor-driven power steering system; and a controller configured to determine whether a reverse steering operation has been performed based on the steering angle or the angular speed, and configured to output, when non-reverse steering, a high-frequency compensation gain (a second gain) based on the column torque, as a final compensation gain, and output, when reverse steering, a value obtained by applying an additional compensation gain (a first gain) optimized corresponding to an angular acceleration to the high-frequency compensation gain (the second gain), as the final compensation gain.

A steering control device (ECU) comprises a base assist unit for generating a basic assist torque and a steering torque correction unit. The steering torque correction unit outputs a corrected steering torque, which is decreasingly corrected so that an absolute value becomes smaller than an absolute value of a steering torque when a viscous load is requested to be applied to a driver by decreasing the assist torque. The base assist unit includes a target steering torque calculation unit and a servo controller. The target steering torque calculation unit calculates the target steering torque based on a steering torque. The servo controller calculates the basic assist torque to cause the corrected steering torque to follow the target steering torque.

A method for unintended steering mitigation includes receiving at least one hand wheel measurement correspond to a hand wheel of a vehicle. The method also includes determining a hand wheel return value corresponding to the at least one hand wheel measurement. The method also includes receiving a torque value corresponding to propulsion of the vehicle. The method also includes determining whether the torque value is above a threshold. The method also includes, in response to a determination that the torque value is above the threshold adjusting the hand wheel return value based on the torque value and selectively controlling return of the hand wheel based on the adjusted hand wheel return value.

The present disclosure relates to a rear-wheel steering system and a controlling method thereof. The rear-wheel steering system includes: a rack configured to transmit a driving force generated from a rear-wheel steering motor to rear wheels; a first correction module configured to, when an engine is started, detect a position of the rack using a displacement sensor and calculate a first correction value that is a difference between the detected position and a neutral position; a second correction module configured to, when the engine is started, detect a position of the rack using a motor position sensor that detects a rotation angle of the rear-wheel steering motor and calculate a second correction value that is a difference between the detected position and the neutral position; a comparison determiner configured to compare the first correction value and the second correction value to determine whether the displacement sensor has malfunctioned; and a steering controller configured to control an operation of the rear-wheel steering motor. Accordingly, it is possible to determine whether an error occurs in the displacement sensor and to return the rack to the neutral position even when the error has occurred in the displacement sensor.

A damping control method of steering system may include determining, by a controller, a basic damping value based on a vehicle velocity, a steering angular velocity, and an output value of a steering motor when it is determined that steering for restoring a steering wheel to a steering angle neutral position is to be performed; determining, by the controller, whether a driver is in a hand-off state in which the driver takes its hands off the steering wheel according to signals reflecting a steering state and a behavior of a vehicle; compensating, by the controller, for the basic damping value so that the basic damping value is increased and determining a final damping value when it is determined that the driver is in the hand-off state; and controlling, by the controller, the steering motor with the final damping value obtained by the compensation, and restoring and steering the steering wheel.

Based on the result of determination by a friction transition state determination unit, an assist command value correction unit corrects a basic assist command value in such a way that the hysteresis width of steering torque at a time of turning steering increases; then, a current driving unit controls a motor current in such a way that the motor current coincides with a current command value obtained by correcting the basic assist command value by use of an assist command correction value.

An embodiment of the present invention allows for application of an assist torque or reaction torque which causes a driver to feel less discomfort. An ECU (600) includes a rack shaft axial force estimating section (620) configured to estimate a rack shaft axial force with reference to a roll rate of a vehicle body.

Technical solutions are described for facilitating an electric power steering (EPS) system for providing a motor torque assist command. An example EPS system includes a first module configured to generate a regulation signal or a tuning signal based on a mode of operation of the EPS system. The EPS system further includes a second module configured to generate a stability signal irrespective of the mode of operation of the EPS system. The EPS system further includes a blending module configured to combine the stability signal with either the regulation signal or the tuning signal to generate an assist motor torque signal for the EPS system.