Vehicle traction control with rough road correction
US6591178B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 2, 2001 |
| Grant date | Jul 8, 2003 |
| Priority date | — |
| Expiry date | Oct 6, 2021 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB60W2552/35
- WIPO fieldTransport
- WIPO sectorMechanical engineering
Abstract
A traction control for a motor vehicle responds to detection of a rough road surface so as to shift control away from propulsion power reduction and toward brake control to an over-spinning driven wheel when the rough road surface is detected. This better adapts the traction control to a road surface that may have a high coefficient of friction but produces intermittent loss of traction due to wheel hop or normal force fluctuations due to the rough road surface. The lower power reduction is obtained by increasing a target brake pressure used to derive a brake pressure error signal from which from which a power reduction command is derived. A delta target brake pressure may also be increased to provide a higher target velocity for the driven wheel propulsion. For even higher levels of road roughness, the traction control reduces the gain of time derivative of a difference between a rotational wheel acceleration of the driven wheel and an undriven wheel rotational acceleration that contributes to the brake modulation, since wheel accelerations are of less use in controlling traction on such a road surface.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.