A turning controller controls turning of each wheel in a vehicle having three or more wheels. The wheels are not mechanically constrained to each other and are turned independently. The turning controller includes turning actuator controllers provided in correspondence with turning actuators for turning each wheel. The turning actuator controllers control a driving current applied to the turning actuators so that a turning angle output by the turning actuator becomes a desired value. A set of a turning actuator and a turning actuator controller corresponding to each of the wheels is a unit. The turning actuator controllers communicates drive limit information, which is information regarding a drive limit of the turning actuator, with each other. The turning actuator controllers also limit a drive of the turning actuator of their own unit based on the drive limit information of their own unit and the other units.

A rear wheel steering system includes a triaxial accelerometer and an electronic control circuit, wherein the triaxial accelerometer is connected to the electronic control circuit. The triaxial accelerometer is configured to detect the current acceleration of the vehicle. The electronic control circuit is configured to generate and output a steering command to control two rear wheels of the vehicle according to at least the current acceleration when the current acceleration is greater than a preset acceleration.

A vehicle with driving and steering rear wheels includes a rear suspension system having a support frame mounted on the vehicle body. For each rear wheel, a wheel support is connected to the frame by oscillating arms. An actuator is mounted on the frame, with control rods, protruding from opposite ends of the actuator body, and connected to the wheel supports by control arms. Within a space between the rear wheels, there is a rear motor or differential. The actuator body is mounted on the frame along a transverse direction spaced apart from an axis of the rear wheels to avoid interference with the motor or differential. The control arms are substantially parallel to a transverse direction perpendicular to the longitudinal direction, or form an angle therewith not exceeding 15 degrees. The control rods are connected to the control arms with the interposition of a transmission.

An actuator includes a motor, a rotation transmitting member, a reverse input preventing device, a converting device, and a rod. The motor includes a rotating shaft. The rotation transmitting member is configured to transmit rotation of the rotating shaft. The reverse input preventing device includes an input member and an output member. The reverse input preventing device is configured to prevent external force input to the output member from being transmitted to the input member. The converting device includes a nut that rotates according to the rotation of the output member. The converting device is configured to convert a rotary motion of the nut into a linear motion. The rod is configured to advance and retract according to the linear motion of the converting device. The input member and the rotation transmitting member are integrated. The output member and the nut are integrated.

A rear-wheel steering apparatus for a vehicle includes: a housing; a driver supported by the housing and configured to generate a driving force; a transmission shaft movably accommodated in the housing and configured to reciprocate by receiving the driving force from the driver; an anti-rotation member fixed to the housing and configured to restrain a rotation of the transmission shaft; and a guide member coupled to the anti-rotation member to be interposed between the transmission shaft and the anti-rotation member and configured to guide a movement of the transmission shaft.

A vehicle rear wheel steering apparatus includes: a housing supported by the rear wheels via first and second connection members; an electric motor supported by the housing; a speed reduction mechanism connected to an output shaft of the electric motor, and reducing the speed of an output of the electric motor; and a linear motion mechanism including a nut member connected to the speed reduction mechanism, and a rod screwed to the nut member and connected to at least one of the first and second connection members, and converting rotational motion of the nut member into linear motion of the rod, wherein the speed reduction mechanism includes a planetary gear mechanism, and the speed of an output of the electric motor is reduced and the reduced output is transmitted to the linear motion mechanism.

It is an object of the present invention to provide a rear wheel steering device of which the weight is not added to unsprung weight, and which can steer right and left rear wheels independently of each other. The rear wheel steering device includes a first rod connected to the left rear wheel, a first driving portion configured to axially move the first rod, a second rod connected to the right rear wheel, a second driving portion configured to axially move the second rod; and a single housing supporting the first rod, the first driving portion, the second rod, and the second driving portion.

A control system for a four-wheel independent steering system includes at least one sensor configured to detect at least one of a shift position of a joystick, mounted on the four-wheel independent steering system, or a driving speed of a vehicle, and a position controller configured to control a position of the joystick based on sensing data detected by the at least one sensor.

The present disclosure relates to a rear wheel steering apparatus and a control method thereof, which can detect stick-slip that may occur during the operation of a rear wheel steering (RWS) system, thereby controlling the performance of a motor in a variable manner, and can control the motor to operate in a limited operation mode only when the stick-slip has occurred during the operation of the RWS system, thereby reducing the noise generated by the stick-slip and the shock transmitted to a vehicle.

The disclosure relates to a method for steering a vehicle via a rear axle steering system that includes an actuator having a steering linkage at least indirectly operable by a threaded drive and longitudinally displaceable within a chassis-fixed housing. The actuator includes a rotor position sensor for detecting a rotor position of a rotor of an electric motor designed for actuating the threaded drive and a linear sensor for detecting an axial position of a target arranged on the steering linkage. The two sensors are connected to a control and analysis unit configured to carry out a comparison between the rotor position and the axial position of the target when there is a defined zero point of an axial position of the steering linkage relative to the housing and, in consideration of a thermal expansion of at least the steering linkage, operating the actuator to adjust the steering angle.