Location detecting method
Patent 4999783 Issued on March 12, 1991. Estimated Expiration Date: 
December 22, 2008. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
December 22, 2008. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent ReferencesNavigation system with capability of instructing running direction System and method for navigating a vehicle Vehicle navigational system and method Vehicle location detecting system Patent #: 4807127 InventorsAssigneeApplicationNo. 295206 filed on 12/22/1988US Classes:701/217, Using dead-reckoning apparatus73/178R, NAVIGATION701/205, Determination of along-track or cross-track deviations701/208, For use in a map data base system701/300RELATIVE LOCATIONExaminersPrimary: Lall, Parshotam S.Assistant: Zanelli, Michael J. Attorney, Agent or FirmForeign Patent References
International ClassG06F 015/50Foreign Application Priority Data1987-05-11 JPAbstractA location detecting method for detecting the location of a vehicle within a predetermined area, comprising the steps of: outputting distance data at every predetermined interval, the distance data being representative of the distance that a vehicle has travelled; outputting heading angle data at every predetermined interval, the heading angle data being representative of the heading angle change of vehicle travel; storing road map data representative of roads; computing a present location data from the distance data and the heading angle data; computing a first limit error (E1) and a second limit error (E2) of the present location data which are determined on the basis of errors in the distance data, in the heading angle data and in the road map data; registering locations on the roads, which roads are located within the first limit error (E1) of the present location data, as estimate locations; computing correlation coefficients respectively corresponding to the registered estimate locations; selecting a correlation coefficient whose error is smallest with respect to the road from the computed correlation coefficients; and outputting the registered estimate location corresponding to the selected correlation coefficient as a present location. | |
