Patent · US Expired

Road surface detecting device

US4809197A · kind A · utility

47Cited by
10References
14Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 24, 1986
Grant dateFeb 28, 1989
Priority date
Expiry dateDec 24, 2006

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB60G2600/16
  • WIPO fieldTransport
  • WIPO sectorMechanical engineering

Abstract

A road surface detecting device has a circular plate connected with an axle of a vehicle so as to be rotated with said axle, and has a large number of teeth at regular intervals in its outer periphery. A rotary sensor detecting the passage of the teeth of the circular plate, and generates a pulse signal, and a microcomputer receive the pulse signal. The microcomputer calculates instantaneous speeds of a wheel from the period of the pulse signal and calculates an average value of a plurality of instantaneous speeds obtained in the predetermined rotations of a wheel another average value of a plurality of instantaneous speeds obtained in the next predetermined rotations of a wheel is also calculated as a presumed speed of a vehicle based on one and another average values. The microcomputer then calculates an absolute value of a difference between the instantaneous speeds in the predetermined rotations after next of a wheel and the presumed speed of vehicle, cancels an absolute value of an oldest difference every time when an absolute value of a newest difference is obtained, and calculates a successive integrated value by adding absolute values of a predetermined number of difference…

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