{
  "$type": "site.standard.document",
  "description": "A vehicle navigation apparatus is capable of detecting a current vehicle position with improved accuracy. The reliability factor of a distance coefficient is reduced when a vehicle runs in an area having a large altitude gradient or when a position detection error is detected between a current…",
  "path": "/patents/1077763",
  "publishedAt": "2005-05-18T00:00:00.000Z",
  "site": "at://did:plc:oql6ds5vnff4ugar6rruliwd/site.standard.publication/3mn3ohu7oxx5w",
  "tags": [
    "G01C21/28",
    "AISIN AW CO [JP]"
  ],
  "textContent": "A vehicle navigation apparatus is capable of detecting a current vehicle position with improved accuracy. The reliability factor of a distance coefficient is reduced when a vehicle runs in an area having a large altitude gradient or when a position detection error is detected between a current vehicle position calculated using the distance coefficient and a current vehicle position calculated based on GPS position data. When the vehicle runs at a high speed, the distance coefficient is modified depending on the running speed. After the distance coefficient is determined via learning, if a position detection error is detected for a road which the vehicle has previously traveled, a position detection cost is assigned to the road. Factors that can cause a position detection error are minimized, thereby making it possible to detect a current vehicle position with high accuracy.",
  "title": "Vehicle navigation apparatus"
}