Patent · US Expired

Road surface state estimating device

US6640623B2 · kind B2 · utility

9Cited by
2References
13Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 15, 2001
Grant dateNov 4, 2003
Priority date
Expiry dateOct 15, 2021

Classification

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

Abstract

In order to estimate a braking force gradient in a low slip region including a steady travelling region, there is provided a device comprising a wheel speed sensor for detecting a wheel speed in a predetermined sampling period and outputting time series data of the wheel speed as a wheel speed signal, a break point frequency estimating section for estimating a break point frequency in a gain diagram that represents a frequency response of a first order lag model that approximates a transmission characteristics from road surface disturbances to wheel speed, and a braking force gradient estimating section for estimating a braking force gradient with respect to the estimated break point frequency on the basis of the map showing a relationship between braking force gradient and break point frequency stored in advance.

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