Patent · US Expired

Road friction coefficients estimating apparatus for vehicle

US6650987B2 · kind B2 · utility

12Cited by
8References
17Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 14, 2001
Grant dateNov 18, 2003
Priority date
Expiry dateNov 14, 2021

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB60T2210/12
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A road friction coefficient estimating apparatus primarily includes an adaptive control road friction coefficient estimating section and an actual value comparison road friction coefficient estimating section. The adaptive control road friction coefficient estimating section inputs signals indicative of a road surface condition with low friction coefficient from a wiper switch, low outside air temperature judging section and the like and estimates an accurate road friction coefficient even under the low friction coefficient road surface condition. When the vehicle travels at high speeds, the actual value comparison road friction coefficient estimating section renders a road friction coefficient estimating value by a yaw rate comparison method gradually close to a road friction coefficient of an asphalted road surface. When a signal IMAGE HALT indicative of a road surface totally covered with snow is inputted, the actual value comparison road friction coefficient estimating section renders the road friction coefficient estimating value gradually close to a low side road friction coefficient produced by the adaptive control road friction coefficient estimating section. Further, when …

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.