Current position calculating system for a vehicle having a function for correcting a vehicle direction
US5839087A · kind A · utility
Inventor
Key dates
| Filing date | Jun 3, 1996 |
| Grant date | Nov 17, 1998 |
| Priority date | — |
| Expiry date | Jun 3, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01C21/30
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A current position calculation system is provided for preventing accuracy in map matching from being degraded due to errors in an angular difference between road and vehicle directions. According to a previously determined vehicle current position and a relative displacement obtained on the basis of the vehicle direction and travelled distance, the vehicle current position is estimated as a virtual current position. A most probable latest current position on a road is determined on the basis of distances from the virtual current position to line segments representing part of roads, respectively, and an angular difference between each of the line segment directions and the vehicle direction. In addition, there are held a plurality of angular differences between road and vehicle directions which are differences between the vehicle directions of predetermined plural number of previously obtained positions, and the line segment directions at each of the previously obtained positions respectively. An averaged value of the plural number of angular differences between road and vehicle directions is obtained. A latest vehicle direction detected by a direction detecting means is modified on…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.