JP-2026074561-A - Steering system

JP2026074561AJP 2026074561 AJP2026074561 AJP 2026074561AJP-2026074561-A

Abstract

[Problem] To ensure that the reaction force is controlled effectively. [Solution] This steering system is a steer-by-wire type equipped with a reaction force device and a steering device. In this steering system, the reaction force is controlled based on the steering angle deviation, which is the difference between the target steering angle and the actual steering angle. Furthermore, the steering angle deviation is a value that has undergone phase adjustment. As a result, the delay in the effect of changes in the steering angle deviation on the reaction force can be suppressed, and the driver can be properly informed of the steering state of the wheels through the reaction force applied to the steering control member. This allows for effective control of the reaction force. [Selection Diagram] Figure 2

Inventors

飯田友幸
三宅純也
松田哲

Assignees

トヨタ自動車株式会社
株式会社ジェイテクト

Dates

Publication Date: 20260507
Application Date: 20241021

Claims (4)

A steer-by-wire steering system installed in a vehicle, A steering device for steering the wheels of the aforementioned vehicle, A reaction force device that applies a reaction force to a steering control member that can be operated by the driver, Includes a control device for controlling the reaction force, A steering system in which the control device controls the reaction force based on a phase-adjusted deviation, which is the difference between the actual steering angle of the wheel and the target steering angle, which is the target value of the steering angle for the wheel, with the phase adjusted.
The steering system according to claim 1, wherein the control device performs a phase adjustment with respect to the target steering angle and acquires the phase-adjusted deviation in accordance with the phase of operation of the steering control member.
The control device includes a steering angle control unit that controls the steering device to control the steering angle of the wheels, and a reaction force control unit that controls the reaction force device to control the reaction force, The steering angle control unit and the reaction force control unit are connected via a connection unit so as to be able to communicate with each other. The steering system according to claim 1 or 2, wherein the control device acquires the phase-adjusted deviation, which has undergone phase lead processing based on the communication delay via the connection part.
The steering system according to claim 1 or 2, wherein the control device obtains a target steering angle, which is the target steering angle, by performing at least one process on the amount of operation of the steering control member, and obtains a phase-adjusted target steering angle by performing phase adjustment on the target steering angle based on the delay occurring in one or more of the at least one processes, thereby obtaining the phase-adjusted deviation.

Description

This invention relates to a steering system installed in a vehicle. Patent Document 1 describes a steer-by-wire steering system equipped with a reaction force device and a steering device. In the reaction force device of this steering system, the reaction force motor is controlled so that a target value of the operating torque, which is the reaction force torque, is achieved. Furthermore, the operating torque is obtained based on the steering angle deviation, which is the difference between the target steering angle and the actual steering angle. The target value of the operating torque is determined by performing a phase lead process on the obtained operating torque. Japanese Patent Publication No. 2023-048612 This diagram conceptually illustrates a steering system according to one embodiment of the present invention.This diagram conceptually shows the steering angle control unit and its surrounding area, which are key components of the steering system described above.This diagram conceptually shows the reaction force control unit and its surrounding area, which are part of the steering system described above.This diagram conceptually shows the steering drive circuit for the steering system described above. The following describes a steering system, which is one embodiment of the present invention, with reference to the drawings. This steering system includes a reaction force device 10 and a steering device 12. The reaction force device 10 and the steering device 12 are mechanically independent of each other; in other words, they are mechanically isolated from each other. This steering system is a steer-by-wire type. The reaction force device 10 includes a steering control member 20, a reaction force transmission mechanism 22, a reaction force actuator 26, etc. The reaction force device 10 transmits the reaction force to the driver via the steering control member 20. The steering control member 20 is operable by the driver and can be a rotatable steering wheel, a joystick capable of reciprocating linearly or curvilinearly, etc. In this embodiment, a rotatable steering wheel is used as the steering control member 20. An input shaft 24 is connected to the steering wheel 20, and a reaction force transmission mechanism 22 is provided on the input shaft 24. The reaction force transmission mechanism 22 can, for example, have multiple gears. A reaction force actuator 26 is connected to the reaction force transmission mechanism 22. The reaction force actuator 26 includes a reaction force motor, but may also include a reduction gear in addition to the reaction force motor. The reaction force torque, which is the output torque of the reaction force actuator 26, is transmitted to the input shaft 24 via multiple gears and then to the steering wheel 20. An operating angle sensor 28, which acts as an operating amount sensor, is attached to the input shaft 24. The operating angle sensor 28 detects the amount of operation of the steering operating member, i.e., the amount of operation from the neutral position. In this embodiment, it detects the operating angle, which is the rotation angle of the steering wheel 20 from the neutral position. The steering device 12 steers the left and right steering wheels. The left and right steering wheels can be, for example, the left and right front wheels FW1 and FW2. In this embodiment, the steering device 12 is a rack and pinion type and includes a steering actuator 30, a steering force transmission mechanism 32, an output shaft 33 (which is the steering output shaft), a pinion gear 34, a rack bar 35, etc. The steering actuator 30 includes a steering motor, but may also include a reduction gear in addition to the steering motor. The rack bar 35 is provided extending in the width direction of the vehicle as its axial direction. The pinion gear 34 is screwed onto the rack bar 35. The steering force transmission mechanism 32 transmits the driving force of the steering actuator 30 to the output shaft 33, causing the output shaft 33 to rotate in accordance with the rotation of the steering actuator 30. The steering force transmission mechanism 32 can, for example, have various gears (e.g., a planetary gear mechanism). The driving force of the steering actuator 30 is transmitted to the steering wheels FW1 and FW2 via the steering force transmission mechanism 32, the output shaft 33, the pinion gear 34, and the rack bar 35. The rotation of the pinion gear 34 displaces the rack bar 35 in the axial direction, and the steering wheels FW1 and FW2 steer left and right in accordance with the axial displacement of the rack bar 35. A steering angle sensor 38 is attached to the output shaft 33. The steering angle sensor 38 detects the rotation angle of the output shaft 33 from the neutral position. Based on the rotation angle of the output shaft 33, the actual steering angle δm of the left and right steering wheels FW1 and FW2 can be obtained. Furthermore, the steering angle sensor can be configured