Method and system for route calculation that avoids railroad crossings

• US 7,400,972 B2
• Filed: 06/14/2004
• Issued: 07/15/2008
• Est. Priority Date: 01/17/2002
• Status: Active Grant

• Current Assignee: HERE Global B.V. (HERE Holding Corporation)
• Original Assignee: Navteq North America LLC (HERE Holding Corporation)
• Inventors: Kozak, Frank J.
• Primary Examiner(s): Beaulieu; Yonel
• Application Number:
  US10/867,545
• Publication Number:
  US 20040243305A1
• Time in Patent Office: 1,492 Days
• Field of Search: 701/200, 701/204, 701208-209, 701/19, 701/20, 246/473.1, 340/995.24
• US Class Current: 701/209
• CPC Class Codes: B61L 29/246 Signals or brake- or lighting devices mounted on the road vehicle and controlled from the vehicle or train
• CPC Class Codes: G01C 21/3461 Preferred or disfavoured areas, e.g. dangerous zones, toll or emission zones, intersections, manoeuvre types, segments such as motorways, toll roads, ferries

Abstract

A navigation system provides information about railroad crossing locations. A geographic database used by the navigation system includes data that indicate whether an at-grade railroad crossing is located along a road segment. Using this information, a route calculation function in the navigation system calculates a route to a destination that avoids road segments that have at-grade railroad crossings. In this way, the delays associated with waiting for a train to cross a road are avoided.

Claims

1. A geographic database that represents road segments, the geographic database comprising:

data entities that represent road segments;

wherein each data entity that represents a road segment that has an at-grade railroad crossing located thereon includes data indicating the at-grade railroad crossing and the location thereof along the road segment.

2. The geographic database of claim 1 wherein each data entity that represents a road segment that has an at-grade railroad crossing located thereon is associated with data that indicates a relative amount of train traffic activity at the at-grade railroad crossing on the represented road segment.

3. The geographic database of claim 1 wherein each data entity that represents a road segment that has an at-grade railroad crossing located thereon is associated with data that indicates times of day associated with levels of train traffic.

4. The geographic database of claim 1 wherein each data entity that represents a road segment that has an at-grade railroad crossing located thereon is associated with data that indicates days of week associated with levels of train traffic.

5. The geographic database of claim 1 further comprising:

train schedule information, wherein each data entity that represents a road segment that has an at-grade railroad crossing located thereon refers to the train schedule information for an indication of train traffic at the at-grade railroad crossing on the represented road segment.

6. The geographic database of claim 1 further comprising:

a table of train traffic activity combinations, wherein each data entity that represents a road segment that has an at-grade railroad crossing located thereon refers to the table of train traffic activity combinations for an indication of train traffic at the at-grade railroad crossing on the represented road segment.