A steering system includes a steering mechanism, a motor that is a source of an assist force, and a battery that supplies a voltage to the motor. The system includes a voltage sensor that detects a power supply voltage, a steering sensor that detects a steering angle, and a motor control signal generation circuit that calculates a q-axis voltage command value to allow the motor to generate the assist force and that generates a motor control signal based on the q-axis voltage command value. The system includes a steering-angular-velocity limiting circuit that calculates a compensation amount for compensation for the q-axis voltage command value and that derives the compensation amount by calculating a power supply compensation component based on the power supply voltage when the absolute value of the steering angle is equal to or larger than a predetermined steering angle close to a maximum steering angle.

A parking assist system parks a vehicle at a target parking position by automatically steering an EPS. The parking assist system includes a acquiring unit configured to acquire the position of the vehicle, a position determining unit configured to determine the target parking position, a generating unit configured to generate a path from the position of the vehicle to the target parking position, a detecting unit configured to detect the temperature of the EPS, and a assist unit configured to automatically steer the vehicle so as to move along the path generated by the generating unit. The generating unit generates a path in which a degree of stationary steering by which the vehicle is steered in a state where the vehicle stops is small when the temperature of the EPS is high, compared with when the temperature of the EPS is low.

An end determination unit determines that a steering apparatus is in an end touching state when an angle deviation, which is a difference between an actual turning angle and a target turning angle, exceeds a threshold. This angle deviation exceeds the threshold before a large axial force is generated in a steering shaft. Accordingly, is it possible to determine that the steering apparatus is in the end touching state more quickly.

A steering system includes a rack housing in which a rack shaft is housed, rack ends fitted to respective end portions of the rack shaft and coupled to respective steered wheels, and shock-absorbing members provided between the rack housing and the respective rack ends. When the rack shaft moves in a direction in which an end face of the rack end approaches a restricting surface of the rack housing and thus the rack shaft reaches a position after the shock-absorbing member is compressed by a compression amount, a control unit creates a normal input end through electronic stopper control of reducing an assisting force to be generated by a motor. This restricts movement of the rack shaft in a direction in which the end face approaches the restricting surface.

In a steering system including a steering operation mechanism, a second actuator, a steering angle sensor, a steering torque sensor, and a steering operation control device and a control method for the steering system, only a drive assist target steered angle (first target steered angle) is reflected in a final target steered angle when a torque sensor value (actual steering torque) detected by the steering torque sensor is equal to or less than an intervention threshold. When the magnitude of the torque sensor value is more than the intervention threshold, the rate of reflection (distribution ratio) of a driver target steered angle (second target steered angle) in the final target steered angle is raised as the torque sensor value is increased, and the rate of reflection of the driver target steered angle in the final target steered angle is lowered as the magnitude of the torque sensor value is decreased.

The present embodiments relate to a steer-by-wire-type steering apparatus, and may provide a steer-by-wire-type steering apparatus comprising: an outer member which is rotated by a driving motor and has oblique grooves formed in the inner circumferential surface thereof; an inner member which is formed in a cylindrical shape and spaced inward from the inner circumferential surface of the outer member, fixed to a steering column, and provided with a guide part open in a radial direction; a sliding member, of which the outer surface is supported by the oblique grooves when the outer member rotates, and which moves along the guide part in an inward radial direction; and a support member which moves in the radial direction in association with the sliding member, and which supports the outer circumferential surface of the steering shaft and thereby prevents the steering shaft from rotating.

A turning control device includes: a steering angular displacement calculation unit configured to, when a third steering angle that is either a first steering angle of a turning mechanism or a second steering angle of a steering mechanism, is in an angular range from a maximum angle to a threshold steering angle, calculate a steering angular displacement of the third steering angle with the threshold steering angle used as a reference; a steering angle correction value calculation unit configured to calculate a steering angle correction value according to at least the steering angular displacement; a steering angle correction value limiting unit configured to limit the steering angle correction value according to at least a steering state, the third steering angle, and angular velocity thereof; a corrected target steering angle calculation unit configured to correct the target steering angle of the turning mechanism with a limited steering angle correction value.

A haptic feedback mechanism for steering by wire system includes a motor. Electronic circuitry includes a node and switches for controlling the motor. A voltage sensor at the node and a motion sensor for the DC motor feed a motor control logic module that is operative to: determine if the voltage at the node is above a predetermined threshold; determine if the input motion is above a predetermined speed; and change the switches into an overcurrent protection mode if the voltage is above the predetermined threshold or the input motion is above the predetermined speed. In overcurrent protection mode, electrical power, generated by the input motion, passes through resistance and/or the motor to dissipate while maintaining haptic feedback. An endstop mechanism includes a position sensor coupled to the haptic feedback mechanism for detecting an angular position of the motor to increase feedback torque near an endstop of the motor.

A steering-angle-limiting device of a steer-by-wire system selectively restricts turning of a steering wheel in a forward direction or in a reverse direction and permits turning of the steering wheel in order to inhibit locking of the steering wheel when the steering-angle-limiting device operates abnormally. Rotation of a stopping gear, which is coupled to a steering shaft, is selectively restricted depending on a change in a rotation angle of a cam, whereby the direction in which the steering wheel turns is selectively limited. In addition, when a stopper operates abnormally, the stopper is moved to a position apart from an end of the radius of rotation of the stopping gear, thereby enabling turning of the steering wheel.

A method for operating a steering mechanism (12) of a motor vehicle, wherein a steering rod (27) can be held or displaced along its longitudinal axis (a) by an electric motor (22) so that the wheel steering angle (8, 9) of at least one wheel (5, 6) on at least one vehicle axle (1) can be maintained or changed. When a force (F.sub.ext) acts essentially axially on the steering rod (27), displacement of the steering rod (27) is at least inhibited by a detent torque (RM) of the electric motor (22) and/or by a self-induced torque (M.sub.sip) of the electric motor. The invention also relates to a device for carrying out the method and to a steering mechanism, which is preferably in the form of a steer-by-wire steering system. A control unit is provided for carrying out the method.