A multifunctional electric recirculating ball steering system for commercial vehicles and its control method are described. The system comprises three modules: an electric power module, a mechanical transmission module, and a control module. The system introduces a dual-rotor motor and a common power motor, working together to act on the input end of a recirculating ball steering gear. The dual-rotor motor offers high redundancy, increased output torque, and improved reliability for control-by-wire operations. A fork assembly enables synchronous and asynchronous rotation of the dual rotors, achieving both steer-by-wire and electric power steering functions. Leveraging the high reduction ratio capability of the recirculating ball steering gear maximizes power torque and simplifies the system architecture while ensuring reliability in both traditional control and control-by-wire functionalities.

Techniques are described for managing redundant steering system for a vehicle. A method includes sending a first control command that instructs a first motor coupled to a steering wheel in a steering system to steer a vehicle, receiving, after sending the first control command, a speed of the vehicle, a yaw rate of the vehicle, and a steering position of the steering wheel, determining, based at least on the speed and the yaw rate, an expected range of steering angles that describes values within which the first motor is expected to steer the vehicle based on the first control command, and upon determining that the steering position of a steering wheel is outside the expected range of steering angles, sending a second control command that instructs a second motor coupled to the steering wheel in the steering system to steer the vehicle.

A vehicle steering intervention system and method prevents a loss of vehicle control condition or a vehicle rollover condition. The system includes a driver input torque sensor for sensing torque applied by a driver to a steering wheel, a steering angle sensor for sensing a steering angle, and a speed determination device for determining a vehicle speed. An electronic power steering unit includes an electronic processor and a memory. The electronic power steering unit determines a vehicle steering intervention threshold based on the torque sensed, the steering angle, and the vehicle speed. The electronic power steering unit predicts whether the vehicle steering intervention threshold will be exceeded within a predetermined time based on a torque gradient and/or a steering angle gradient. When the vehicle steering intervention threshold is predicted to be exceeded, the electronic power steering unit reduces a power steering assist and/or provides a counter steer force.

A vehicle steering device includes a first setting portion 41 that sets a target assist torque in accordance with a steering torque, a second setting portion 42 that sets an angle controlling target torque for bringing an angular deviation between a target steering angle and an actual steering angle close to zero, an estimator that estimates a compensation object 43 load with respect to the angle controlling target torque, a first calculating portion 44 that calculates a target automatic steering torque based on the angle controlling target torque set by the second setting portion and the compensation object load estimated by the estimator, and a second calculating portion 44 that performs weighted addition of the target automatic steering torque and the target assist torque in accordance with a value that changes in accordance with a driver input to calculate a target motor torque that is a target value of a motor torque of the electric motor.

A steer by wire type steering apparatus comprises an input shaft having one end coupled to a reducer and having an input gear formed on an outer circumferential surface of another end to transmit driving force of a motor, an output shaft having an output gear coupled to the input gear formed on one side of an outer circumferential surface, a first gear coupled to one end, and a pitman arm coupled to another end, a sensor shaft having one end coupled to a second gear coupled to the first gear, and an angle sensor coupled to an outer circumferential surface of the sensor shaft to detect a rotational angle of the sensor shaft and transmit the rotational angle of the sensor shaft to an electronic control device.

A vehicle steering assist device in which the steering assist ECU calculates a target steering angle for driving a vehicle along a traveling path, and is vehicle steering assist device that a calculates a target steering guide torque for facilitating the steering angle to become a target steering angle by reducing a return torque for urging the steering wheel to a neutral position in an area where the steering angle is smaller than the target steering angle, wherein when the steering angular velocity is higher than the target steering angular velocity, the steering support ECU calculates a target steering angular velocity control torque acting in a direction opposite to a direction in which the steering angle changes, and controls the control steering torque generating device so as to generate a control steering torque including a sum of the target steering guide torque and the target steering angular velocity control torque.

An electromechanically assisted steering system is proposed, having a worm drive which comprises a worm shaft and a worm gear, an electric motor which has a drive shaft, and a spring element. At an end assigned to the electric motor, the worm shaft has a first bearing portion which is connected to the drive shaft in a torque-transmitting manner. The worm shaft has a second bearing portion which is arranged at an end of the worm shaft remote from the first bearing portion. The spring element is connected to the first bearing portion or to the second bearing portion so as to transmit axial force in the axial direction, such that the spring element axially pretensions the worm shaft relative to the worm gear. A tolerance compensation of the worm drive in the axial direction of the worm shaft is carried out exclusively via the spring element.

A steering wheel structure for an omnidirectional mobile robot chassis is provided. The steering wheel structure can realize two degrees of freedom: the rudder rotation of the steering wheel rotation and the full free movement realized in the horizontal plane, it has the characteristics of a small size and a lower height. The wheel assembly realizes the movement of the steering wheel when it moves forward; the rudder assembly realizes the movement of the steering wheel when the steering wheel rotates, initializes the steering direction, and calibrates the rotation through the zero position sensor; the suspension assembly realizes the damping and buffering of the longitudinal motion of the steering wheel; the wiring assembly constrains the movement of various wires when the rudder rotates; the support plate is used for the connection and support of the wheel assembly and the wiring assembly with the rudder assembly.

To improve steering feeling felt by a driver, a motor control device includes a processor and a memory which stores a program for controlling an operation of the processor. According to the program, the processor executes: switching from n-phase (n is an integer of three or more) energization control to n−1 phase energization control in response to a switching signal; acquiring a torque command value, an electrical angle of a motor, and an actual current value of the motor; generating a pre-current command value on the basis of the torque command value, the electrical angle of the motor, and the actual current value of the motor which are acquired; generating a current command value by applying dither control to the pre-current command value in a dead point range of an electrical angle range from 0 to 2π; and performing the n−1 phase energization control on the basis of the current command value.

A steering control device in a seer-by-wire system calculates a current limit presentation command value so as to convey an output-limited state of a turning device to a driver, calculates a steering torque command value on a basis of a physical quantity corresponding to an output torque of the turning device, and calculates a basic reaction force torque command value being a basic value of a reaction force torque command value so that a detection value of a torque sensor follows a target value that is based on the steering torque command value. The control device controls a current flowing to a reaction-force-use rotary electric machine on a basis of the basic reaction force torque command value and the end presentation command value, and increases an absolute value of the current limit presentation command value when the turning device is in the output-limited state.