Disclosed is a steer by wire system that includes a controller operable to operate a roadwheel actuator such that a position command to the roadwheel actuator based on a handwheel orientation is a magnitude corresponding to a handwheel orientation offset value in an opposite direction to reduce a difference between the handwheel orientation offset value and a predetermined handwheel zero value.

The present invention relates to a method and a system for vehicle steering control comprising controlling a feedback torque actuator (130) in series with an angle overlay actuator (140) in a vehicle steering system (100), where said feedback torque actuator (130) is controlled in such a way that a target feedback torque is achieved and said angle overlay actuator (140) is controlled in such a way that a target overlay angle is achieved. The feedback torque actuator (130) is arranged above said angle overlay actuator (140), i.e. towards the steering wheel side, and the method comprises the steps of: controlling said angle overlay actuator (140) so that a variable steering ratio as well as an additional overlay angle are provided, and controlling said torque feedback actuator (130) using a reference generator so that the torque is controlled in such a way that a target steering feel is achieved, resulting in the angle overlay being controlled at the same time as the steering-wheel torque being controlled whereby a target overlay angle and a good steering feel are achieved.

An electric steering column device includes a column housing, and a first shaft, a connection shaft and a second shaft provided in the column housing. The connection shaft is movable in an axial direction of the first shaft and the second shaft and is connected to the first shaft and the second shaft so as to rotate together with the first shaft and the second shaft. The first and second shaft are connected to the connection shaft so that the first shaft always rotates at the same rotation speed and that a rotation speed of the second shaft is varied depending on whether or not the connection shaft moves in the axial direction. The device is capable of securing an optimized steering performance by adjusting steering responsibility of a steering wheel depending on a driving state of the vehicle.

A steering assist apparatus on a vehicle is provided, including a steering drive unit that drives a steering apparatus; a steering control unit that executes an automatic steering mode in which the steering drive unit is controlled such that a turning angle is determined based on at least either a running state of the vehicle or road information to accomplish the determined turning angle; and a transmission ratio determining unit that determines, based on at least either a running state of the vehicle or the road information, a first transmission ratio in the automatic steering mode to be a value different from a second transmission ratio in a manual steering mode in which the steering apparatus operates in accordance with the steering angle inputted via a steering input apparatus.

To provide a method of manufacturing a shaft for a steering device, the shaft including a spline shaft part to be coupled with an input shaft, a stopper part to be coupled with an output shaft, and an intermediate shaft part that couples the spline shaft part with the stopper part. The method includes: a step of forming a hole part recessed in an axial direction from one end of a pillar-shaped material by forging; and a step of pressing the material in which the hole part has been formed into a die to perform drawing in a radial direction on a portion of the material at which the stopper part is formed and prolonging a length along the axial direction of the hole part at the same time by forging.

A steering/turning controller: inputs a target turning angle command created based on travel environment information; determines whether the target turning angle command is a corrective turning region, in which an angle is equal to or less than an angle threshold value and an angular velocity is equal to or greater than an angular velocity threshold value, or a non-corrective turning region other than the corrective turning region; when generating a steering command angle and a turning command angle based on the target turning angle command, sets a distribution of the steering command angle to zero and generates only the turning command angle in the case of the corrective turning region; and generates the steering command angle and the turning command angle in the case of the non-corrective turning region.

In a vehicle, an amount of change of a turning angle of a turning mechanism to an amount of change of a steering angle of a steering input device is defined as a transfer ratio, the turning mechanism is rotationally driven by a turning drive unit, and a driver's body posture parameter is detected by a body posture parameter detector. An apparatus for steering the vehicle includes a controller that executes an automatic steering mode that determines a target value for the turning angle of the turning mechanism based on a travelling condition of the vehicle and/or information about a road on which the vehicle is travelling, and controls the turning mechanism to adjust the turning angle of the turning mechanism to the target value. A transfer ratio adjuster adjusts the transfer ratio in accordance with the body posture parameter during execution of the automatic steering mode.

The present invention provides a vehicle control device and method capable of ensuring steering accuracy. In a vehicle provided with a left-right pair of steered wheels for which the braking/driving forces can each be controlled, and a steering force generation device that generates steering force for the steered wheels and controls the steering angle of the steered wheels, this vehicle control device and method control the steering force and the steering reaction force from the steering force generation device by controlling the braking/driving force of each of the steered wheels on the basis of the lateral force acting on the steered wheels.

A steering/turning controller: inputs a target turning angle command created based on travel environment information; determines whether the target turning angle command is a corrective turning region, in which an angle is equal to or less than an angle threshold value and an angular velocity is equal to or greater than an angular velocity threshold value, or a non-corrective turning region other than the corrective turning region; when generating a steering command angle and a turning command angle based on the target turning angle command, sets a distribution of the steering command angle to zero and generates only the turning command angle in the case of the corrective turning region; and generates the steering command angle and the turning command angle in the case of the non-corrective turning region.

A microcomputer includes a current command value setting unit configured to set a two-phase current command value in a two-phase rotating coordinate system for each of PWM cycles in a current control cycle, and an open-loop control unit configured to calculate a two-phase voltage command value for each of the PWM cycles, according to a motor voltage equation, based on the two-phase current command value for each of the PWM cycles that is set by the current command value setting unit and a rotation speed of an electric motor. The two-phase voltage command value is a command value of voltage that is to be applied to the electric motor.