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:
Dec. 24, 1996
Filed:
Sep. 09, 1994
Dan Negrin, Wiesbaden, DE;
Kelsey-Hayes Company, Livonia, MI (US);
Abstract
A method and system for detecting an incorrect indication of front-rear locked four-wheel drive operation of a vehicle capable of both front-rear locked four-wheel drive and unlocked two-wheel drive. The relative speed difference, defined as the absolute value of the difference between the rear wheel velocity and the arithmetic average of the front wheel velocities divided by the vehicle reference speed, is measured repeatedly. A count of measured relative speed differences greater than a relative speed threshold is calculated. The incorrect indication is detected when the count exceeds a rejection threshold. The relative speed threshold is predetermined based on histograms of relative speed data for two-wheel drive and four-wheel drive modes of operation. Once an incorrect indication is detected, modifications are made to the antilock brake system control algorithm.