Navigation system and method using map data
US5311173A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 28, 1991 |
| Grant date | May 10, 1994 |
| Priority date | — |
| Expiry date | Aug 28, 2011 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01C21/30
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
In a navigation system which has sensors for detecting a running distance, an azimuth, etc. of a vehicle, and a memory for storing map data; a probability density of a position of the vehicle is calculated on the basis of the sensor outputs and the map data for each of quantization units with which a probability computation determined by detection accuracies of the sensors and quantization of the map data can be executed. In addition, a final stage calculation of DP matching between trajectory data obtained from the on-board sensor data from a start point of the vehicle until a current time and a candidate route estimated from the road map data is iteratively executed, whereby a plurality of estimative vehicular positions and uncertainties (costs) corresponding to the respective estimative positions are iteratively evaluated, and a correct vehicular position is estimated by selecting at least one estimative vehicular position of low uncertainty (cost).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.