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:
May. 01, 2001
Filed:
Aug. 30, 1999
Denso Corporation, Kariya, JP;
Abstract
Navigation system, which can improve an accuracy of a travel distance calculation and an accuracy of present position detection even if an accuracy of a pulse data from a vehicle speed sensor is relatively low. The navigation system includes a gyroscope, a vehicle speed sensor and a navigation control portion. The navigation control portion calculates the travel direction based on outputs from the gyroscope and the vehicle speed sensor. When the vehicle decelerates, acceleration during low speed less than Vmin, in which the vehicle speed pulse is not outputted, is assumed to be equal to an acceleration just before the vehicle speed becomes less than Vmin. When the vehicle accelerates, acceleration during low speed less than Vmin, in which the vehicle speed pulse is not outputted, is assumed to be equal to an acceleration just after the vehicle speed becomes to or more than Vmin. Vehicle present position is calculated by estimating travel distances Dist,and Dist,which are estimated to travel during a pulse-missing period at deceleration and acceleration, and adding them to the travel distance Dist calculated based on the vehicle speed pulse from the vehicle speed sensor.