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:
Sep. 05, 1989
Filed:
Dec. 08, 1987
John W Crayton, Washington, IL (US);
Charles T Kinas, Peoria, IL (US);
Scott G Sinn, Morton, IL (US);
Caterpillar Inc., Peoria, IL (US);
Abstract
A self guided vehicle employs a highly accurate velocity sensor to determine vehicle speed and position. The velocity sensor includes a resolver connected to and rotatable with a ground engaging wheel. A resolver to digital converter (R/D) provides a highly accurate 8-bit digital signal representative of the angle of wheel rotation. A second less expensive and less accurate velocity sensor also receives the modulated sine and cosine signals from the resolver and produces a series of pulses representative of vehicle speed. The pulses are produced by detecting the zero crossings of the sine, cosine, and combinations of the sine and cosine signals. The velocity information present in the second velocity sensor signal is not used to actually guide the vehicle, but merely to generally validate the information present in the R/D signal.