Method and apparatus for estimating road surface state and tire running state, ABS and vehicle control using the same
US7203579B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 20, 2002 |
| Grant date | Apr 10, 2007 |
| Priority date | — |
| Expiry date | Dec 20, 2022 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB60T2210/13
- WIPO fieldTransport
- WIPO sectorMechanical engineering
Abstract
The frequency of an information signal indicative of a-vibration of a wheel detected by an acceleration sensor mounted to a wheel; or a change in the pressure of a gas in a tire detected by a pressure sensor installed in the tire, is analyzed. The band value of the obtained vibration spectrum or pressure change spectrum is detected, and a vibration level or pressure change level at the detected frequency band is compared with: a vibration level table showing the relationship between road friction coefficient μ and vibration level; or a pressure change level table showing the relationship between road friction coefficient μ and pressure change level, to estimate a road friction coefficient μ. Therefore, it is possible to estimate the value of road friction coefficient μ accurately and improve the safety of a car.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.