An independent corner module includes an axle fastened to and positioned on a wheel, a steering frame fastened to the axle and rotated integrally with the axle to apply a steering angle to the wheel, a vehicle body guide rail positioned on a vehicle body and fastened to a rotation center axis of the steering frame, a steering driving portion positioned between the steering frame and the vehicle body guide rail to apply a driving force, and a leaf spring unit positioned between the axle and the steering frame, in which the steering driving portion is rotated along the vehicle body guide rail in response to the driving force of the steering driving portion, and at a same time, the steering frame is configured to be rated around the steering driving portion.

A method for power saving in a steering system of a motor vehicle including a road wheel actuator acting on a rack to turn steerable road wheels and a controller configured or programmed to generate an operation signal for the road wheel actuator, wherein the controller includes a position controller to generate a motor torque request based on an actual and/or a measured position of the rack and a requested rack position, includes detecting a passive mode of the steering system by a passive mode detector of the controller if the motor vehicle is stopped and no steering input is provided, and if a passive mode is detected by the passive mode detector, setting the motor torque request to zero in order to save power.

A method to control a steer-by-wire steering system for a road vehicle including a steering device, a road wheel actuator to actuate road wheels, and a controller configured or programmed to generate a motor torque request for the road wheel actuator based on an actual or an estimated position and a position request, which is based on the position of the steering device, includes detecting a road wheel actuator power limit situation, modifying the position request so that it can be followed by the road wheel actuator within power limits, and using the modified position request to generate the motor torque request for the road wheel actuator.

A method to control a steer-by-wire steering system of a road vehicle including a steering wheel coupled to a steering shaft, a road wheel actuator to turn steerable road wheels, a shaft sensor to detect a rotation of the steering shaft and a controller configured or programmed to generate an operation signal for the road wheel actuator from a signal detected by the shaft sensor, includes determining a real steering wheel angle by the shaft sensor, modifying the real steering wheel angle by applying an artificial hysteresis to create an offset between the real steering wheel angle and a modified steering wheel angle to mimic a behavior of an electromechanical power steering mechanism, and generating the motor torque request for the road wheel actuator based on the modified steering wheel angle.

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.

A steer by wire type steering apparatus according to the embodiments of the present disclosure may comprise a screw shaft having an outer screw portion formed on an outer circumferential surface and rotating in association with a steering shaft, a moving member having an inner screw portion corresponding to the outer screw portion formed on the inner circumferential surface, coupled to the outer circumferential surface of the screw shaft, moving in the axial direction when the screw shaft is rotated, and provided with a radially protruding guide portion on the outer circumferential surface, and a housing provided with a guide groove in which the guide portion is inserted and supported on an inner circumferential surface.

A steer by wire type steering apparatus according to the embodiments of the present disclosure may comprise a rotating member having a spiral guide hole penetrating through one side and the other side in the axial direction and rotating in conjunction with a steering shaft, a housing in which the rotating member is built, a housing cover coupled to one end of the housing, and a guide pin inserted in the axial direction into the guide hole, one end supported by the housing and the other end supported by the housing cover.

A turning device includes a turning shaft having a first ball screw groove as one of a left screw and a right screw and a second ball screw groove as the other of the left screw and the right screw and turning wheels to be turned by moving in an axial direction, a first electric motor generating a first driving force, a second electric motor operating independently of the first electric motor and generating a second driving force, a first ball screw nut transmitting the first driving force generated by the first electric motor to the first ball screw groove, a second ball screw nut transmitting the second driving force generated by the second electric motor to the second ball screw groove, and a rotation regulating part regulating relative rotation of the turning shaft around an axis with respect to a housing.

A steering control device controls an assist torque to be outputted by a motor connected to a steering system mechanism generating a steering torque. A response compensation filter performs a filter process compensating for a response in a specific frequency band with respect to a target steering torque generated by a target generation unit, and outputs a response-compensated target steering torque (Ts**). A servo controller calculates an assist torque command value (Ta*) in order for a torque deviation (ΔTs), which is a difference between the steering torque (Ts) and the response-compensated target steering torque (Ts**), to become zero. A transfer characteristic of the response compensation filter is set to suppress a mechanical resonance frequency band where a gain due to resonance of the steering system mechanism becomes large.

According to embodiments of the present invention, the maximum rotation angle of a steering wheel can be easily changed, the steering feel provided to a driver can be enhanced by improved noise performance, and the durability of components can be improved.