Apparatus for visually indicating the current location of an automotive vehicle
US4521777A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 16, 1982 |
| Grant date | Jun 4, 1985 |
| Priority date | — |
| Expiry date | Aug 16, 2002 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01C21/28
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A current location indicating apparatus for use in an automotive vehicle wherein a current location of the automotive vehicle is arithmetically obtained in terms of two-dimensional coordinates by a signal processing unit on the basis of the outputs from a travel distance detecting unit and a bearing detecting unit, and the current location of the vehicle is visually indicated on the screen of a display from the thus-obtained data in connection with the current location thereof. The apparatus comprises, in operative combination, a first bearing detecting unit employing an earth magnetism sensor as a primary component, a second auxiliary detecting unit employing a rate type gyroscope or the like, and a signal processing unit adapted to monitor the output from the first bearing detecting unit in comparison with the operating state of the second auxiliary bearing detecting unit to determine whether or not the earth magnetism sensor of the first bearing detecting unit is under the influence of any external disturbances for a short period so that the output of the first bearing detecting means can be corrected accordingly.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.