Patent · US Expired

Vehicle speed estimation for antilock braking using a chassis accelerometer

US5579230A · kind A · utility

19Cited by
16References
3Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 10, 1991
Grant dateNov 26, 1996
Priority date
Expiry dateJun 10, 2011

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB60T2250/04
  • WIPO fieldTransport
  • WIPO sectorMechanical engineering

Abstract

Before braking occurs the speed of non-driven wheels is monitored and averaged to determine vehicle speed and an integrator is initialized with that speed. Acceleration is periodically calculated from the vehicle speed, stored in a ring buffer and averaged. The output of a chassis accelerometer is also sampled during the same periods and stored in a similar ring buffer and averaged. Accelerometer bias due to slope or drift is determined as the difference of the two averaged accelerations. The noise level of the accelerometer bias is determined by filtering and rectification. After braking occurs, the accelerometer output is corrected by subtracting the bias and the noise and is then used to continuously update the integrator output to provide an estimate of vehicle speed during braking.

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