Variable steering ratio control system and method
US6799105B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 1, 2002 |
| Grant date | Sep 28, 2004 |
| Priority date | — |
| Expiry date | Oct 23, 2022 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S706/913
- WIPO fieldTransport
- WIPO sectorMechanical engineering
Abstract
The present invention involves a system and method of controlling a variable steering ratio of a vehicle steer-by-wire system. The variable steering ratio control varies the steering ratio continuously according to steering angle and vehicle speed. The method comprises sensing an actual steering wheel angle and an actual speed of the vehicle and converting the actual steering wheel angle and vehicle speed into values in fuzzy sets based on a steering wheel angle and vehicle speed membership functions with linguistic term labels. The method further includes determining a corresponding degree of membership of the steering wheel angle and vehicle speed. The method further includes inferring a fuzzy road wheel reference angle output value by determining the degree of membership function for the road wheel reference angle using fuzzy rules based on the degrees of steering angle and the vehicle speed. The method further includes converting a fuzzy road wheel angle into an actual road wheel angle. The variable steering ratio can be adjusted according to the vehicle operator's desire with a progressive ratio setup.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.