Peter G Snider

US Patent:

55089313, Apr 16, 1996

Filed:

Jul 25, 1994

Appl. No.:

8/280031

Inventors:

Peter Snider - San Carlos CA

Assignee:

Zexel Corporation - Tokyo

International Classification:

G06F16500

US Classification:

364449

Abstract:

The invention provides a route state filter for a vehicle route guidance system for improved tracking of vehicle position with respect to a preselected route. A set of position possibilities are derived by comparing a measured vehicle position to a database containing data representing a map of roads, the possibilities corresponding to possible positions on the roads within an error region around the measured position. A route guidance module receives the position possibilities, checks their validity and applies a filter to remove less likely possibilities. A current position is then selected from the remaining possibilities. An ON/OFF ROUTE status of the vehicle is determined by comparing the selected position with the selected route information in the database. A distance-based filter is utilized to provide improved continuity in the route status determination. The route status is then used to set the system operating mode, and instructional information such as maneuvers, distances, and warnings are communicated to the driver.

US Patent:

53595297, Oct 25, 1994

Filed:

May 15, 1992

Appl. No.:

7/884749

Inventors:

Peter Snider - San Carlos CA

Assignee:

Zexel Corporation

International Classification:

G06F 1550

US Classification:

364449

Abstract:

The invention provides a route state filter for a vehicle route guidance system for improved tracking of vehicle position with respect to a preselected route. A set of position possibilities are derived by comparing a measured vehicle position to a database containing data representing a map of roads, the possibilities corresponding to possible positions on the roads within an error region around the measured position. A route guidance module receives the position possibilities, checks their validity and applies a filter to remove less likely possibilities. A current position is then selected from the remaining possibilities. An ON/OFF ROUTE status of the vehicle is determined by comparing the selected position with the selected route information in the database. A distance-based filter is utilized to provide improved continuity in the route status determination. The route status is then used to set the system operating mode, and instructional information such as maneuvers, distances, and warnings are communicated to the driver.