The invention relates to a method for predicting maintenance/replacement period for a component of a vehicle, the vehicle comprising a power-assisted steering system including a steering actuator (14) configured to assist in steering the vehicle at least as compensation for angular deviations of the road wheels (16) caused by road disturbances. The method comprises acquiring over time steering output data indicative of a magnitude and/or frequency of assisted steering as compensation for angular deviations of the road wheels (16) caused by road disturbances, comparing the acquired steering output data with stored component wear data, the stored component wear data being indicative of when maintenance/replacement of the component is due based on wear caused by road disturbances, and determining, based on the comparison of the acquired steering output data and the stored component wear data, whether or not maintenance/replacement of the component is due. The invention also relates to a system (10).

An electric power steering system includes an electric actuator, a current indication value generation unit, an actuator control unit, and a noise signal generation unit. The electric actuator is configured to apply assist force to a steering device. The steering device is configured to turn a steering wheel of a vehicle. The current indication value generation unit is configured to generate a current indication value in accordance with a target value of the assist force. The actuator control unit is configured to supply electric power to the electric actuator in accordance with the current indication value. The noise signal generation unit is configured to add a noise signal to the current indication value. The noise signal has a dominant frequency that is a frequency matching a control clock frequency of the vehicle or a harmonic component of the control clock frequency.

The present embodiments may provide a steering control method and a steering control device capable of compensating for shimmy even when the torque sensor fails and removing only shimmy components without affecting the steering feel by compensating for shimmy using the road wheel actuator-side rack force signal, rather than the steering feedback actuator-side torque signal.

A method for the gradual activation and deactivation of a steering return function in a vehicle, the vehicle including at least two wheels, a steering wheel, an assist motor applying an assist torque to a steering rack, and a drive motor applying a wheel torque to the wheels, the method including a step of calculating an application gain including a first phase of determining a first gain dependent on the wheel torque of at least one of the two wheels, a step of estimating the assist torque associated with the return function, and a step of multiplying the assist torque associated with the return function and the application gain, wherein during the application gain calculation step the method also includes a second phase of determining a second gain dependent on the angle of the steering wheel and the difference in the rotation speeds of the at least two wheels.

A motor control device controls an electric motor in a steering system including a hydraulic mechanism that applies a part of a turning force to a turning mechanism and the electric motor that applies the other part of the turning force. The motor control device includes: an actual turning angle acquiring unit configured to acquire an actual turning angle of turning wheels; a target turning angle acquiring unit configured to acquire a target turning angle which is a target value of a turning angle; a control value generating unit configured to generate a motor control value for controlling the electric motor such that the actual turning angle reaches the target turning angle; and an instruction value calculating unit configured to generate an instruction value which is obtained by filtering a natural frequency of the steering system in response to the motor control value.

A manual steering command value generation unit generates a manual steering command value using steering torque. An integrated angle command value computation unit computes an integrated angle command value by adding the manual steering command value to an automatic steering command value. A control unit performs angle control on an electric motor on the basis of the integrated angle command value. The control unit includes: a basic torque command value computation unit that computes a basic torque command value on the basis of the integrated angle command value; a disturbance torque estimation unit that estimates disturbance torque other than motor torque that is generated by the electric motor and acts on an object to be driven by the electric motor; and a disturbance torque compensation unit that corrects the basic torque command value in accordance with the disturbance 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.

A apparatus for controlling a steer-by-wire system including: a reaction torque generator configured to generate reaction torque as a calculated value of steering reaction torque applied to a steering wheel; a driver torque estimator configured to detect a driver torque estimation value as an estimated value of driver steering torque; a speed controller configured to generate a motor torque command value of a motor-driven power steering system; a torque adjuster configured to calibrate the motor torque command value and the reaction torque based on the driver torque estimation value, and output final active return torque and final reaction torque; and a target current generator configured to generate a target current for motor control by using the final active return torque and the final reaction torque, inputted from the torque adjuster, and input the generated target current to a motor.

Disclosed herein are Motor-Driven Power Steering (MDPS) and a control method thereof. The MDPS includes an information detection unit configured to detect information about the behavior of a vehicle; and a controller configured to receive the information about the behavior of the vehicle from the information detection unit, to determine whether the vehicle is accelerating and whether the vehicle pulls to one side, and to generate compensation torque and drive a driving motor based thereon.

A method for estimating a longitudinal force difference ΔFx acting on steered axle wheels of a vehicle, the method comprising obtaining data from the vehicle related to an applied steering torque M.sub.steer associated with the steered axle wheels, obtaining a scrub radius value r.sub.s associated with the steered axle wheels, and estimating the longitudinal force difference ΔFx, based on the obtained data and on the scrub radius r.sub.s, as proportional to the applied steering torque M.sub.steer and as inversely proportional to the scrub radius r.sub.s.