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:
Feb. 20, 2001
Filed:
Jun. 27, 1997
James R. Geschke, Holland, MI (US);
Thomas R. Olson, Holland, MI (US);
Mark Michmerhuizen, Holland, MI (US);
Gregory B. Colon, Grand Rapids, MI (US);
Prince Corporation, Holland, MI (US);
Abstract
An electronic compass system of the present invention includes a sensor for detecting the earth's magnetic field and for providing electrical signals representing the direction of the vehicle, a heading indicator for indicating vehicle headings in response to received vehicle heading signals, and a processor coupled to the sensor for receiving the electrical signals and coupled to the heading indicator for supplying the vehicle heading signals to the heading indicator. The processor preferably includes a first compass controller for calculating vehicle headings in response to the received electrical signals using precalibration data to compensate for expected vehicular magnetism, a second compass controller for calculating vehicle headings in response to the received electrical signals using an automatic calibration routine to compensate for actual vehicular magnetism, and a control transferring mechanism for initially selecting the vehicle headings calculated by the first compass controller to be represented by the vehicle heading signal supplied to the heading indicator, and for selecting the vehicle headings calculated by the second compass controller after the automatic calibration routine has acquired sufficient data from the magnetic field sensor to calibrate the compass system. The heading indicator may include a display and/or an audio messaging device for generating audible vehicle heading messages. If such an audible messaging device is employed, the device may also be used to record and playback dictated memos.