The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 24, 2001
Filed:
Feb. 18, 2000
Tamotsu Yamaura, Kanagawa, JP;
Unisia Jecs Corporation, Kanagawa, JP;
Abstract
A road surface condition determination system for an automotive vehicle comprises wheel-speed sensors, and a control unit being configured to be electrically connected to the wheel-speed sensors for data-processing a wheel-speed data signal. The control unit calculates a wheel-speed fluctuation of each of the road wheels on the basis of a previous value of the wheel-speed data signal and a current value of the wheel-speed data signal, and calculates an absolute value of the wheel-speed fluctuation of each of the road wheels. A integration circuit is provided to produce a first integrated value of the absolute values of the wheel-speed fluctuations of the road wheels. A smoothing circuit is provided to make a smoothing operation to the integrated value to produce a smoothed value. A road-surface condition determining section is also provided to determine a road surface condition on the basis of the smoothed value. In an automotive vehicle with an ABS system, a skid control section uses the result of discrimination between good and bad roads, executed by the road-surface condition determining section, so as to vary a pressure-reduction threshold depending on the road surface condition detected.