A handwheel actuator for a steer by wire system may include a feedback actuator and a column for operably coupling a handwheel to the handwheel actuator. The column includes a column shaft extending from a first end of the column to a second end of the column. The feedback actuator is operably coupled to the second end of the column and provides tactile feedback to an operator responsive to movement of the handwheel. The feedback actuator includes a torsion bar coaxial with the column shaft. The column shaft is supported relative to a housing of the column by a first column shaft bearing disposed proximate to the first end of the column and a second column shaft bearing disposed proximate to the second end of the column. The torsion bar is operably coupled to a sleeve element that is operably coupled to the column shaft proximate to the second column shaft bearing to facilitate torque transfer between the column shaft and the torsion bar.

Machine-learning-based steering torque non-uniformity compensation for vehicles is enabled. For example, a system can comprise a memory that stores computer executable components, and a processor that executes the computer executable components stored in the memory, wherein the computer executable components comprise: a machine learning component that generates a steering non-uniformity model based on machine learning applied to past steering data representative of positions and steering ratios of a steering wheel of a vehicle, and a torque compensation component that, using current position data representative of a current position of the steering wheel and the steering non-uniformity model, determines a torque to apply to the steering wheel configured to offset a steering non-uniformity at the current position.

A motor control system shorts motor windings of a motor by using enhancement metal-oxide-semiconductor field-effect transistors (MOSFETs) so that the motor generates braking torque when all or some electric control units of the motor are disabled or failed. The motor control system comprises: a motor comprising a plurality of motor phase terminals; a plurality of electric control units electrically connected to the motor and configured to control the motor, wherein the electric control units configured to output control signals, respectively; a plurality of power sources, each of the power sources electrically connected to a respective one of the electric control units; and a shorting circuit connected between the power sources and the motor, the shorting circuit configured to selectively short the motor phase terminals in response to one or more of the control signals of the electric control units.

A steering column assembly is disclosed that comprises: an elongate rotatable steering column, a displacement motor, a torque feedback motor; an engagement mechanism and a control. The steering column is configured at one end for attachment of a steering member and is displaceable along its longitudinal axis between a withdrawn, stowed position in which the steering function of the steering column is inhibited and an extended, deployed position in which the steering function of the steering column can be enabled. The displacement motor displaces the steering column between the stowed and deployed positions. The torque feedback motor is connected to the steering column and by which the steering column is rotatable. The engagement mechanism is engaged when the steering column is in the stowed position and limits the angular displacement of the steering column to a predetermined value. A control is configured to control the operation of the displacement motor and torque feedback motor and to inhibit and enable the steering function of the steering column.

A steering feedback unit detects a steering torque generated according to an operation of a steering wheel, a road-wheel steering unit connected to the steering feedback unit to allow a steering of a wheel to be performed according to a steering angle or the steering torque transmitted from the steering feedback unit, and a control unit determines the steering torque detected in the steering feedback unit as a steering angle selectively according to a preset standard vehicle speed and standard steering speed to transmit the determined steering angle to the road-wheel steering unit, and controls the steering of the wheel according to the steering angle to be performed, or transmits the steering torque detected in the steering feedback unit to the road-wheel steering unit and control the amount of motor torque for the steering of the wheel to be determined.

Described herein are steer-by-wire systems and methods of operating these systems in vehicles. A steer-by-wire system comprises a steering wheel assembly, comprising a steering wheel, sensors, and a torque generator. The system comprises a rack assembly, comprising a steering rack, sensors, and a rack actuator. The steering wheel assembly and the rack assembly are communicatively coupled by a steer-by-wire system controller, without having any direct mechanical links between the assemblies. In some examples, the controller instructs the rack assembly to control the steering rack position based on the steering input, such as changes in the steering wheel position. A steering map is used to determine the desired steering rack position based on the current steering wheel position. In some examples, a steering map is selected from a steering map set based on, e.g., the vehicle speed, vehicle direction, driver preference, and the like.

A steer-by-wire system for a land vehicle, having a steering wheel, a feedback actuator, a detection device equipped to detect a driver's intention to enter the vehicle and/or a driver's intention to exit the vehicle, and an electronic control system, which, following detection of the intention to enter the vehicle and/or the intention to exit the vehicle controls the feedback actuator to hold the steering wheel in a predetermined rotational position by generating a holding torque. When an actuating torque which exceeds the holding torque is applied manually to the steering wheel and the steering wheel is rotated out of the predetermined rotational position, the electronic control system continuously approximates a turning angle of the predetermined rotational position to a turning angle of a current rotational position of the steering wheel using a specified time-based adjustment function based on a difference between the actuating torque and the holding torque.

According to the present embodiments, it is possible to enhance the driver's steering feel with a simplified structure, reduce components, save manufacturing and processing costs, and prevent overshoot to secure the driver's safety.

A steer-by-wire system includes a steering reaction torque generation device mechanically separated from a turning device for turning wheels and configured to apply a reaction torque to a steering wheel. The steering reaction torque generation device has a duplex configuration including a first system and a second system, each system including a reaction torque motor. When both systems are normal, a control device generates the reaction torque having a normal characteristic by controlling an operation of the reaction torque motor of at least one system. In a case of single failure where one of the systems fails, the control device generates the reaction torque having a first characteristic by controlling an operation of the reaction torque motor of another of the systems. The reaction torque having the first characteristic is different from the reaction torque having the normal characteristic with respect to a same steering angle.

According to one or more embodiments, a steer by wire steering system includes a handwheel, and a handwheel actuator configured to secure a position of the handwheel. The securing includes determining a transition of the steer by wire steering system to an ingress/egress mode. The securing further includes, based on the determination that the steer by wire steering system is in the ingress/egress mode, computing a holding torque command based on a difference in a present angle of the handwheel and a target angle of the handwheel, which is caused by an input torque. Further, the securing includes generating a holding torque corresponding to the holding torque command to secure the position of the handwheel.