Power boost during degradation of a steering system

Patent metadata

Field	Value
Publication number	US-12441394-B2
Application number	US-202418612477-A
Country	US
Kind code	B2
Filing date	Mar 21, 2024
Priority date	Sep 22, 2021
Publication date	Oct 14, 2025
Grant date	Oct 14, 2025

Abstract

A method of controlling a steering system for a vehicle includes determining a state of performance degradation of the steering system, determining a vehicle situation, determining if a performance of the steering system in the determined state of performance degradation is sufficient for the determined vehicle situation, and, if the performance of the steering system is not sufficient, modifying the state of performance degradation by decreasing a degradation level for a period of time.

First claim

What is claimed is:

1. A method to control a steering system for a vehicle, the method comprising:
(a) determining a state of performance degradation of the steering system;
(b) determining a vehicle situation;
(c) determining if a performance of the steering system in the determined state of performance degradation is sufficient for the determined vehicle situation; and
(d) if the performance of the steering system is determined to be not sufficient, modifying the state of performance degradation by decreasing a degradation level for a period of time.

2. The method according to claim 1 , wherein the vehicle situation determined in step b) is an emergency situation of the vehicle.

3. The method according to claim 1 , wherein in step d), the degradation level is decreased to a level with sufficient performance of the steering system to provide full steering functionality for the determined vehicle situation.

4. The method according to claim 1 , wherein the decrease of degradation level in step d) is carried out for a period of time sufficient for the vehicle situation to change.

5. The method according to claim 1 , wherein the determination of the vehicle situation in step b) is based on one or more of a vehicle speed, a lateral acceleration, a longitudinal acceleration, a yaw rate, feedback actuator signals or road wheel actuator signals.

6. The method according to claim 1 , wherein in step d), the modifying of degradation is carried out dependent on the state of performance degradation of the steering system.

7. The method according to claim 1 , wherein in step d), the degradation is gradually decreased.

8. The method according to claim 7 , wherein a rate of degradation decrease is at least one of a tunable parameter or is vehicle speed dependent.

9. The method according to claim 7 , wherein the degradation is decreased up to a limit value, which is a tunable parameter and which depends on at least one of an original degradation level or a vehicle speed.

10. The method according to claim 1 , wherein, in step d), the period of time is a tunable parameter dependent on at least one of an original degradation level or a vehicle speed.

11. The method according to claim 1 , wherein after step d), the degradation is increased back to an original state of performance degradation determined in step a).

12. The method according to claim 11 , wherein a rate of increase during step d) is at least one of a tunable parameter or is vehicle speed dependent.

13. A steer-by-wire steering system configured to perform the method according to claim 1 .

14. An electric power assisted steering system for a vehicle with a controller configured to perform the method according to claim 1 .

Assignees

• Thyssenkrupp Presta Ag
• Honda Motor Co Ltd

Inventors

• Kakas Péter
• Arányi Miklós
• Yamaguchi Takaya
• Ojima Yosuke
• Kuribayashi Takashi

Classifications

• B62D6/008

  Control of feed-back to the steering input member, e.g. simulating road feel in steer-by-wire applications · CPC title

• B62D5/0484 Primary

  for reaction to failures, e.g. limp home · CPC title

• B62D5/001

  Mechanical components or aspects of steer-by-wire systems, not otherwise provided for in this maingroup · CPC title

• B62D5/0481 Primary

  monitoring the steering system, e.g. failures · CPC title