Steering control apparatus

• US 9,988,076 B2
• Filed: 03/09/2017
• Issued: 06/05/2018
• Est. Priority Date: 03/15/2016
• Status: Active Grant

• Current Assignee: Jtekt Corporation (Toyota Motor Corporation)
• Original Assignee: Jtekt Corporation (Toyota Motor Corporation)
• Inventors: Kodera, Takashi, Yamano, Naoki, Itamoto, Hidenori, Yamashita, Yoshihiro, Anraku, Koji
• Primary Examiner(s): Black, Thomas G
• Assistant Examiner(s): Li, Ce Li
• Application Number:
  US15/454,438
• Publication Number:
  US 20170267276A1
• Time in Patent Office: 453 Days
• CPC Class Codes: B62D 5/0412 the axes of motor and steering column being parallel
• CPC Class Codes: B62D 5/0463 calculating assisting torque from the motor based on driver input
• CPC Class Codes: B62D 6/002 computing target steering angles for front or rear wheels B62D7/159 takes precedence
• CPC Class Codes: B62D 6/008 Control of feed-back to the steering input member, e.g. simulating road feel in steer-by-wire applications
• CPC Class Codes: B62D 6/04 responsive only to forces disturbing the intended course of the vehicle, e.g. forces acting transversely to the direction of vehicle travel
• CPC Class Codes: B62D 6/08 responsive only to driver input torque

Abstract

A steering control apparatus includes a steering angle feedback processing unit and an operation signal generation processing unit that operate a reaction force actuator to adjust a steering angle to a target steering angle that is a target value for the steering angle based on feedback control, an ideal-axial-force calculation unit that calculates an ideal axial force, a road-surface-axial-force calculation unit that calculates a road surface axial force, an axial-force allocation calculation unit that calculates a base reaction force in which the ideal axial force and the road surface axial force are allocated in a predetermined ratio, and a target steering angle calculation processing unit that sets a target steering angle based on the base reaction force. The steering angle feedback processing unit feeds back the target steering angle in which road surface information is incorporated through the road surface axial force, so that the steering angle is controlled.

Claims

1. A steering control apparatus that outputs an operation signal to a steering system, the steering control apparatus comprising:

a control apparatus including a processor and a memory, the memory storing instructions that, when executed by the processor, cause the processor to function as a reaction force processing unit that outputs the operation signal to the steering system to control a reaction force acting against an operation of a steering wheel performed on the steering wheel, wherein

the steering system includes;

a reaction force actuator that applies a reaction force and a steering operation actuator that applies a force for steering the steered wheels at least while power is not transmitted between steered wheels and the steering wheel, and

the reaction force processing unit has;

a steering angle control processing unit that operates the reaction force actuator so as to adjust a detection value of a steering angle to a target steering angle that is a target value for the steering angle based on feedback control;

an ideal-component calculation unit that calculates an ideal component in which road surface information transmitted from a road surface to steered wheels is not incorporated;

a road surface component calculation unit that calculates a road surface component in which the road surface information is incorporated;

an allocated component calculation unit that calculates an allocated component in which the ideal component and the road surface component are allocated in a ratio, wherein the allocated component calculation unit varies the ratio in which the ideal component and the road surface component are allocated according to a state of a vehicle; and

a target steering angle calculation processing unit that sets the target steering angle based on the allocated component.

2. The steering control apparatus according to claim 1, further comprising:

a steered angle control processing unit that operates the steering operation actuator so as to adjust a detection value of a rotation angle of a rotating shaft convertible into a steered angle of the steered wheels to a target steered angle that is a target value for the rotation angle based on feedback control;

wherein

the ideal-component calculation unit calculates, as the ideal component, an ideal transmission force that is an ideal value for a transmission force acting on the steered wheels based on at least one of the target steering angle and the target steered angle, and

the road surface component calculation unit calculates the transmission force acting on the steered wheels as the road surface component based on an actual current value of the steering operation actuator.

3. The steering control apparatus according to claim 1, wherein

the allocated component calculation unit is configured to enable allocation of a rate of the ideal component allocated in the allocated component when the ideal component is assumed to be 1 and a rate of the road surface component allocated in the allocated component when the road surface component is assumed to be 1 such that a sum of the rates is larger than 1.

4. A steering control apparatus that outputs an operation signal to a steering system, the steering control apparatus comprising:

a control apparatus including a processor and a memory, the memory storing instructions that, when executed by the processor, cause the processor to function as an assist force processing unit that outputs the operation signal to the steering system to assist an operation of a steering wheel to steer the steered wheels, wherein

the steering system includes an assist force actuator that applies an assist force that assists the operation of the steering wheel, and

the assist force processing unit has;

a steered angle control processing unit that operates the assist force actuator so as to adjust a detection value of a rotation angle of a rotating shaft that is convertible into a steered angle of the steered wheels to a target steered angle that is a target value for the rotation angle based on feedback control;

an ideal-component calculation unit that calculates an ideal component in which road surface information transmitted from a road surface to the steered wheels is not incorporated;

a road surface component calculation unit that calculates a road surface component in which the road surface information is incorporated;

an allocated component calculation unit that calculates an allocated component in which the ideal component and the road surface component are allocated in a ratio, wherein the allocated component calculation unit varies the ratio in which the ideal component and the road surface component are allocated according to a state of a vehicle; and

a target steered angle calculation processing unit that sets the target steered angle based on the allocated component.

5. The steering control apparatus according to claim 4, wherein

the ideal-component calculation unit calculates an ideal transmission force that is an ideal value for a transmission force acting on the steered wheels, as the ideal component, based on the target steered angle, and

the road surface component calculation unit calculates the transmission force acting on the steered wheels as the road surface component based on an actual current value of the assist force actuator.