Enhanced inertial measurement unit/global positioning system mapping and navigation process

• US 6,622,090 B2
• Filed: 09/26/2001
• Issued: 09/16/2003
• Est. Priority Date: 09/26/2000
• Status: Expired due to Term

• Current Assignee: American GNC Corporation
• Original Assignee: American GNC Corporation
• Inventors: Lin, Ching-Fang
• Primary Examiner(s): Louis-Jacques, Jacques H.
• Application Number:
  US09/968,410
• Publication Number:
  US 20020062193A1
• Time in Patent Office: 720 Days
• Field of Search: 701/207, 701/213, 701/224, 701/215, 701/217, 701/220, 701/221, 701/214, 342/357.01, 342/357.06, 342/357.02, 342/357.12, 342/357.14, 342/358
• US Class Current: 701/213
• CPC Class Codes: G01C 21/165 combined with non-inertial navigation instruments
• CPC Class Codes: G01S 19/49 whereby the further system is an inertial position system, e.g. loosely-coupled

Abstract

The present invention relates generally to a geospatial database access and query method, and more particularly to a map and Inertial Measurement Unit/Global Positioning System (IMU/GPS) navigation process. With the location information provided by an IMU/GPS integrated system, the geospatial database operations, such as database access and query, are sped up. With the map data from a geospatial database, the navigation performance and accuracy are enhanced. The present invention also supports real time mapping by using IMU/GPS integrated system as the positioning sensor.

Claims

1. An enhanced inertial measurement unit/global positioning system and map navigation process, comprising the steps of:

(a) receiving a position from an inertial measurement unit/global positioning system device;

(b) retrieving geospatial data from a geospatial map database based on said position from said inertial measurement unit/global positioning system device through the steps of;

(b-1) defining an access area based on said position from said inertial measurement unit/global positioning system device and a geographic extent, wherein said position from said inertial measurement unit/global positioning system device is a center of said access area, and said geographic extent is input by a user;

(b-2) performing an IMU/GPS-based database matching process to derive an involved geospatial database, wherein said geographic extent of said access area is compared with a geographic extent of said geospatial database to check whether said access area is included in said geospatial database, intersects with said geospatial database, or is excluded from said geospatial database;

(b-3) performing an IMU/GPS-based involved tile finding process on said involved databases to derive involved tiles, wherein said tile is geographically subdividing a coverage solely for a purpose of enhancing data management, wherein a tile index file is used to retrieve a geographic extent of said tile, and said geographic extent of said access area is compared with said geographic extent of said tile to check whether said access area is included in said tile, intersects with said tile, or is excluded from said tile; and

(b-4) performing an IMU/GPS-based primitive access process on said involved tiles, wherein said IMU/GPS-based primitive access comprises an IMU/GPS-based node access, an IMU/GPS-based edge access, and an IMU/GPS-based area access, wherein said primitive includes a node, an edge, and an area, wherein said node, said edge, and said area in said involved tiles are retrieved;

(c) performing time-space filtering based on said position and said retrieved geospatial data from said geospatial map database to derive a displaying position for said user; and

(d) displaying a trajectory of said user on a graphic displaying unit, which tracks a motion of said user.

2. An enhanced inertial measurement unit/global positioning system and map navigation process, as recited in claim 1, wherein the step (c) further comprises the steps of:

(c-1) forming a predicted position by predicting a next position of said user based on a current position and velocity of said user from said inertial measurement unit/global positioning system device;

(c-2) calculating a true position of said user based on said predicted position of said user and a measured position from said inertial measurement unit/global positioning system device, wherein said true position of said user is an average position of said predicted position of said user and said measured position from said inertial measurement unit/global positioning system device;

(c-3) computing a distance from said true position of said user to a road neighboring said true position of said user; and

(c-4) comparing said distance from said true position of said user to said road neighboring said true position of said user with a threshold, wherein said threshold is preset based on an accuracy of said inertial measurement unit/global positioning system device, and said position mark of said user is displayed on said road when said distance from said true position of said user to said road neighboring said true position of said user is less than said threshold, wherein said position mark of said user is displayed at said calculated true position when said distance from said true position of said user to said road neighboring of said true position of said user is larger than said threshold.

3. An enhanced inertial measurement unit/global positioning system and map navigation process, as recited as claim 1 or 2, wherein said inertial measurement unit/global positioning system device comprises a micro IMU, a GPS receiver and means for blending measurements from said micro IMU and said GPS receiver, and said enhanced inertial measurement unit/global positioning system and map navigation process further comprising a step of feeding said true position from said time-space filtering process to said means for blending measurements from said micro IMU and said GPS receiver to further correct navigation error.

4. An enhanced inertial measurement unit/global positioning system and map navigation process, comprising the steps of:

(a) receiving a position from an inertial measurement unit/global positioning system device;

(b) retrieving geospatial data from a geospatial map database based on said position from said inertial measurement unit/global positioning system device through the steps of;

(b-1) defining an access area based on said position from said inertial measurement unit/global positioning system device and a geographic extent, wherein said position from said inertial measurement unit/global positioning system device is a center of said access area, and said geographic extent is input by a user;

(b-2) performing an IMU/GPS-based database matching process to derive an involved geospatial database, wherein said geographic extent of said access area is compared with a geographic extent of said geospatial database to check whether said access area is included in said geospatial database, intersects with said geospatial database, or is excluded from said geospatial database;

(b-3) performing an IMU/GPS-based involved tile finding process on said involved databases to derive involved tiles, wherein said tile is geographically subdividing a coverage solely for a purpose of enhancing data management, wherein a tile index file is used to retrieve a geographic extent of said tile, and said geographic extent of said access area is compared with said geographic extent of said tile to check whether said access area is included in said tile, intersects with said tile, or is excluded from said tile; and

(b-4) performing an IMU/GPS-based primitive access process on said involved tiles, wherein said GPS-based primitive access comprises an IMU/GPS-based node access, an IMU/GPS-based edge access, and an IMU/GPS-based area access, wherein said primitive includes a node, an edge, and an area, wherein said node, said edge, and said area in said involved tiles are retrieved;

(c) displaying said retrieved geospatial data on said graphic displaying unit as a background;

(d) performing time-space filtering based on said position and said retrieved geospatial data from said geospatial map database to derive a displaying position for said user; and

(e) displaying a trajectory of said user on a graphic displaying unit, which tracks a motion of said user.

5. An enhanced inertial measurement unit/global positioning system and map navigation process, as recited in claim 4, wherein the step (d) further comprises the steps of:

(d-1) forming a predicted position by predicting a next position of said user based on a current position and velocity of said user from said inertial measurement unit/global positioning system device;

(d-2) calculating a true position of said user based on said predicted position of said user and a measured position from said inertial measurement unit/global positioning system device, wherein said true position of said user is an average position of said predicted position of said user and said measured position from said inertial Measurement unit/global positioning system device;

(d-3) computing a distance from said true position of said user to a road neighboring said true position of said user; and

(d-4) comparing said distance from said true position of said user to said road neighboring said true position of said user with a threshold, wherein said threshold is preset based on an accuracy of said inertial measurement unit/global positioning system device, and said position mark of said user is displayed on said road when said distance from said true position of said user to said road neighboring said true position of said user is less than said threshold, wherein said position mark of said user is displayed at said calculated true position when said distance from said true position of said user to said road neighboring of said true position of said user is larger than said threshold.

6. An enhanced inertial measurement unit/global positioning system and map navigation process, as recited as claim 4 or 5, wherein said inertial measurement unit/global positioning system device comprises a micro IMU, a GPS receiver and means for blending measurements from said micro IMU and said GPS receiver, and said enhanced inertial measurement unit/global positioning system and map navigation process further comprising a step of feeding said true position from said time-space filtering process to said means for blending measurements from said micro IMU and said GPS receiver to further correct navigation error.

7. An enhanced inertial measurement unit/global positioning system and map navigation process, comprising the steps of:

(a) receiving a position from an inertial measurement unit/global positioning system device;

(b) retrieving geospatial data from a geospatial map database based on said position from said inertial measurement unit/global positioning system device through the steps of;

(b-1) defining an access area based on said position from said inertial measurement unit/global positioning system device and a geographic extent, wherein said position from said inertial measurement unit/global positioning system device is a center of said access area, and said geographic extent is input by a user;

(b-2) performing an IMU/GPS-based database matching process to derive an involved geospatial database, wherein said geographic extent of said access area is compared with a geographic extent of said geospatial database to check whether said access area is included in said geospatial database, intersects with said geospatial database, or is excluded from said geospatial database;

(b-3) performing an IMU/GPS-based involved tile finding process on said involved databases to derive involved tiles, wherein said tile is geographically subdividing a coverage solely for a purpose of enhancing data management, wherein a tile index file is used to retrieve a geographic extent of said tile, and said geographic extent of said access area is compared with said geographic extent of said tile to check whether said access area is included in said tile, intersects with said tile, or is excluded from said tile; and

(b-4) performing an IMU/GPS-based primitive access process on said involved tiles, wherein said GPS-based primitive access comprises an IMU/GPS-based node access, an IMU/GPS-based edge access, and an IMU/GPS-based area access, wherein said primitive includes a node, an edge, and an area, wherein said node, said edge, and said area in said involved tiles are retrieved;

(c) displaying said retrieved geospatial data on said graphic displaying unit as a background;

(d) performing time-space filtering based on said position and said retrieved geospatial data from said geospatial map database to derive a displaying position for said user;

(e) displaying an accurate position of said user on said graphic displaying unit as a mark; and

(f) displaying a trajectory of said user on a graphic displaying unit, which tracks a motion of said user.

8. An enhanced inertial measurement unit/global positioning system and map navigation process, as recited in claim 7, wherein the step (d) further comprises the steps of:

(d-1) forming a predicted position by predicting a next position of said user based on a current position and velocity of said user from said inertial measurement unit/global positioning system device;

(d-2) calculating a true position of said user based on said predicted position of said user and a measured position from said inertial measurement unit/global positioning system device, wherein said true position of said user is an average position of said predicted position of said user and said measured position from said integrated inertial measurement unit/global positioning system device;

(d-3) computing a distance from said true position of said user to a road neighboring said true position of said user; and

(d-4) comparing said distance from said true position of said user to said road neighboring said true position of said user with a threshold, wherein said threshold is preset based on an accuracy of said inertial measurement unit/global positioning system device, and said position mark of said user is displayed on said road when said distance from said true position of said user to said road neighboring said true position of said user is less than said threshold, wherein said position mark of said user is displayed at said calculated true position when said distance from said true position of said user to said road neighboring of said true position of said user is larger than said threshold.

9. An enhanced inertial measurement unit/global positioning system and map navigation process, as recited as claim 7 or 8, wherein said inertial measurement unit/global positioning system device comprises a micro IMU, a GPS receiver and means for blending measurements from said micro IMU and said GPS receiver, and said enhanced inertial measurement unit/global positioning system and map navigation process further comprising a step of feeding said true position from said time-space filtering process to said means for blending measurements from said micro IMU and said GPS receiver to further correct navigation error.

10. An enhanced inertial measurement unit/global positioning system and map navigation process, comprising steps of:

(a) receiving a measured position from an integrated inertial measurement unit/global positioning system device, wherein said integrated inertial measurement unit/global positioning system device comprises a micro IMU, a GPS receiver and means for blending measurements from said micro IMU and said GPS receiver;

(b) retrieving geospatial data from a geospatial map database based on said measured position from said integrated inertial measurement unit/global positioning system device by using a tile index file, wherein said tile index file stores geographic extent information of tiles which are geographically subdividing a coverage solely for a purpose of enhancing data management;

wherein a geographic extent of an access area is compared with said geographic extent of said tiles to derive a plurality of involved tiles for said access area;

(c) performing time-space filtering based on said measured position and said retrieved geospatial data from said geospatial map database to derive a displaying position for a user;

wherein said measured position and a previous position and a previous velocity are used to derive a true position for said user;

(d) displaying a trajectory of said user on a graphic displaying unit, which tracks a motion of said user;

(e) defining said access area based on said measured position from said integrated inertial measurement unit/global positioning system device and said geographic extent, wherein said measured position from said integrated inertial measurement unit/global positioning system device is a center of said access area, and said geographic extent is input by said user; and

(f) performing an IMU/GPS-based database matching process to derive an involved geospatial database, wherein said geographic extent of said access area is compared with a geographic extent of said geospatial database to check whether said access area is included in said geospatial database, intersects with said geospatial database, or is excluded from said geospatial database.

11. An enhanced inertial measurement unit/global positioning system and map navigation process, as recited in claim 10, wherein the step (c) further comprises the steps of:

(c-1) forming a predicted position by predicting a current position of said user based on said previous position and said previous velocity of said user from said integrated inertial measurement unit/global positioning system device; and

(c-2) calculating a true position of said user based on said predicted position of said user and said measured position from said integrated inertial measurement unit/global positioning system device, wherein said true position of said user is an average position of said predicted position of said user and said measured position from said integrated inertial measurement unit/global positioning system device.

12. An enhanced inertial measurement unit/global positioning system and map navigation process, as recited in claim 11, wherein the step (c) further comprises the steps of:

(c-3) computing a distance from said true position of said user to a road neighboring said true position of said user; and

(c-4) comparing said distance from said true position of said user to said road neighboring said true position of said user with a threshold, wherein said threshold is preset based on an accuracy of said integrated inertial measurement unit/global positioning system device, and said position mark of said user is displayed on said road when said distance from said true position of said user to said road neighboring said true position of said user is less than said threshold, wherein said position mark of said user is displayed at said calculated true position when said distance from said true position of said user to said road neighboring of said true position of said user is larger than said threshold.

13. An enhanced inertial measurement unit/global positioning system and map navigation process, as recited as claim 12, further comprising a step of:

feeding said true position from said time-space filtering process to said means for blending measurements from said micro IMU and said GPS receiver to further correct navigation error.

14. An enhanced inertial measurement unit/global positioning system and map navigation process, as recited as claim 10, further comprising a step of:

feeding said true position from said time-space filtering process to said means for blending measurements from said micro IMU and said GPS receiver to further correct navigation error.

15. An enhanced inertial measurement unit/global positioning system and map navigation process, as recited as claim 14, further comprising a step of:

feeding said true position from said time-space filtering process to said means for blending measurements from said micro IMU and said GPS receiver to further correct navigation error.

16. An enhanced inertial measurement unit/global positioning system and map navigation process, as recited as claim 10, further comprising a step of performing an IMU/GPS-based primitive access process on said involved tiles, wherein said IMU/GPS-based primitive access comprises an IMU/GPS-based node access, an IMU/GPS-based edge access and an IMU/GPS-based area access, wherein said primitive includes a node, an edge and an area, wherein said node, said edge and said area in said involved tiles are retrieved.

17. An enhanced inertial measurement unit/global positioning system and map navigation process, as recited in claim 16, wherein the step (c) further comprises the steps of:

(c-1) forming a predicted position by predicting a current position of said user based on said previous position and said previous velocity of said user from said integrated inertial measurement unit/global positioning system device;

(c-2) calculating a true position of said user based on said predicted position of said user and said measured position from said integrated inertial measurement unit/global positioning system device, wherein said true position of said user is an average position of said predicted position of said user and said measured position from said integrated inertial measurement unit/global positioning system device.

18. An enhanced inertial measurement unit/global positioning system and map navigation process, as recited in claim 17, wherein the step (c) further comprises the steps of:

(c-3) computing a distance from said true position of said user to a road neighboring said true position of said user; and

(c-4) comparing said distance from said true position of said user to said road neighboring said true position of said user with a threshold, wherein said threshold is preset based on an accuracy of said integrated inertial measurement unit/global positioning system device, and said position mark of said user is displayed on said road when said distance from said true position of said user to said road neighboring said true position of said user is less than said threshold, wherein said position mark of said user is displayed at said calculated true position when said distance from said true position of said user to said road neighboring of said true position of said user is larger than said threshold.

19. An enhanced inertial measurement unit/global positioning system and map navigation process, as recited as claim 18, further comprising a step of:

feeding said true position from said time-space filtering process to said means for blending measurements from said micro IMU and said GPS receiver to further correct navigation error.

20. An enhanced inertial measurement unit/global positioning system and map navigation process, comprising steps of:

(a) receiving a measured position from an integrated inertial measurement unit/global positioning system device, wherein said integrated inertial measurement unit/global positioning system device comprises a micro IMU, a GPS receiver and means for blending measurements from said micro IMU and said GPS receiver;

(b) retrieving geospatial data from a geospatial map database based on said measured position from said integrated inertial measurement unit/global positioning system device by using a tile index file, wherein said tile index file stores geographic extent information of tiles which are geographically subdividing a coverage solely for a purpose of enhancing data management;

wherein a geographic extent of an access area is compared with said geographic extent of said tiles to derive a plurality of involved tiles for said access area;

(c) performing time-space filtering based on said measured position and said retrieved geospatial data from said geospatial map database to derive a displaying position for a user;

wherein said measured position and a previous position and a previous velocity are used to derive a true position for said user;

(d) displaying a trajectory of said user on a graphic displaying unit, which tracks a motion of said user;

(e) displaying said retrieved geospatial data on said graphic displaying unit as a background;

(f) defining said access area based on said measured position from said integrated inertial measurement unit/global positioning system device and said geographic extent, wherein said measured position from said integrated inertial measurement unit/global positioning system device is a center of said access area and said geographic extent is input by said user; and

(g) performing an IMU/GPS-based database matching process to derive an involved geospatial database, wherein said geographic extent of said access area is compared with a geographic extent of said geospatial database to check whether said access area is included in said geospatial database, intersects with said geospatial database, or is excluded from said geospatial database.

21. An enhanced inertial measurement unit/global positioning system and map navigation process, as recited in claim 20, wherein the step (c) further comprises the steps of:

(c-1) forming a predicted position by predicting a current position of said user based on said previous position and said previous velocity of said user from said integrated inertial measurement unit/global positioning system device; and

(c-2) calculating a true position of said user based on said predicted position of said user and said measured position from said integrated inertial measurement unit/global positioning system device, wherein said true position of said user is an average position of said predicted position of said user and said measured position from said integrated inertial measurement unit/global positioning system device.

22. An enhanced inertial measurement unit/global positioning system and map navigation process, as recited in claim 21, wherein the step (c) further comprises the steps of:

(c-3) computing a distance from said true position of said user to a road neighboring said true position of said user; and

(c-4) comparing said distance from said true position of said user to said road neighboring said true position of said user with a threshold, wherein said threshold is preset based on an accuracy of said integrated inertial measurement unit/global positioning system device, and said position mark of said user is displayed on said road when said distance from said true position of said user to said road neighboring said true position of said user is less than said threshold, wherein said position mark of said user is displayed at said calculated true position when said distance from said true position of said user to said road neighboring of said true position of said user is larger than said threshold.

23. An enhanced inertial measurement unit/global positioning system and map navigation process, as recited as claim 22, further comprising a step of:

feeding said true position from said time-space filtering process to said means for blending measurements from said micro IMU and said GPS receiver to further correct navigation error.

24. An enhanced inertial measurement unit/global positioning system and map navigation process, as recited as claim 20, further comprising a step of:

feeding said true position from said time-space filtering process to said means for blending measurements from said micro IMU and said GPS receiver to further correct navigation error.

25. An enhanced inertial measurement unit/global positioning system and map navigation process, as recited as claim 20, further comprising a step of performing an IMU/GPS-based primitive access process on said involved tiles, wherein said IMU/GPS-based primitive access comprises an IMU/GPS-based node access, an IMU/GPS-based edge access and an IMU/GPS-based area access, wherein said primitive includes a node, an edge and an area, wherein said node, said edge and said area in said involved tiles are retrieved.

26. An enhanced inertial measurement unit/global positioning system and map navigation process, as recited in claim 25, wherein the step (c) further comprises the steps of:

(c-1) forming a predicted position by predicting a current position of said user based on said previous position and said previous velocity of said user from said integrated inertial measurement unit/global positioning system device; and

(c-2) calculating a true position of said user based on said predicted position of said user and said measured position from said integrated inertial measurement unit/global positioning system device, wherein said true position of said user is an average position of said predicted position of said user and said measured position from said integrated inertial measurement unit/global positioning system device.

27. An enhanced inertial measurement unit/global positioning system and map navigation process, as recited in claim 26, wherein the step (c) further comprises the steps of:

(c-3) computing a distance from said true position of said user to a road neighboring said true position of said user; and

(c-4) comparing said distance from said true position of said user to said road neighboring said true position of said user with a threshold, wherein said threshold is preset based on an accuracy of said integrated inertial measurement unit/global positioning system device, and said position mark of said user is displayed on said road when said distance from said true position of said user to said road neighboring said true position of said user is less than said threshold, wherein said position mark of said user is displayed at said calculated true position when said distance from said true position of said user to said road neighboring of said true position of said user is larger than said threshold.

28. An enhanced inertial measurement unit/global positioning system and map navigation process, as recited as claim 27, further comprising a step of:

feeding said true position from said time-space filtering process to said means for blending measurements from said micro IMU and said GPS receiver to further correct navigation error.

29. An enhanced inertial measurement unit/global positioning system and map navigation process, as recited as claim 25, further comprising a step of:

feeding said true position from said time-space filtering process to said means for blending measurements from said micro IMU and said GPS receiver to further correct navigation error.

30. An enhanced inertial measurement unit/global positioning system and map navigation process, comprising steps of:

(b) receiving a measured position from an integrated inertial measurement unit/global positioning system device, wherein said integrated inertial measurement unit/global positioning system device comprises a micro IMU, a GPS receiver and means for blending measurements from said micro IMU and said GPS receiver;

(b) retrieving geospatial data from a geospatial map database based on said measured position from said integrated inertial measurement unit/global positioning system device by using a tile index file, wherein said tile index file stores geographic extent information of tiles which are geographically subdividing a coverage solely for a purpose of enhancing data management;

wherein a geographic extent of an access area is compared with said geographic extent of said tiles to derive a plurality of involved tiles for said access area;

(c) performing time-space filtering based on said measured position and said retrieved geospatial data from said geospatial map database to derive a displaying position for a user;

wherein said measured position and a previous position and a previous velocity are used to derive a true position for said user;

(d) displaying a trajectory of said user on a graphic displaying unit, which tracks a motion of said user;

(e) displaying said retrieved geospatial data on said graphic displaying unit as a background;

(g) displaying an accurate position of said user on said graphic displaying unit as a mark;

(h) defining said access area based on said measured position from said integrated inertial measurement unit/global positioning system device and said geographic extent, wherein said measured position from said integrated inertial measurement unit/global positioning system device is a center of said access area and said geographic extent is input by said user; and

(i) performing an IMU/GPS-based database matching process to derive an involved geospatial database, wherein said geographic extent of said access area is compared with a geographic extent of said geospatial database to check whether said access area is included in said geospatial database, intersects with said geospatial database, or is excluded from said geospatial database.

31. An enhanced inertial measurement unit/global positioning system and map navigation process, as recited in claim 30, wherein the step (c) further comprises the steps of:

(c-1) forming a predicted position by predicting a current position of said user based on said previous position and said previous velocity of said user from said integrated inertial measurement unit/global positioning system device; and

(c-2) calculating a true position of said user based on said predicted position of said user and said measured position from said integrated inertial measurement unit/global positioning system device, wherein said true position of said user is an average position of said predicted position of said user and said measured position from said integrated inertial measurement unit/global positioning system device.

32. An enhanced inertial measurement unit/global positioning system and map navigation process, as recited in claim 31, wherein the step (c) further comprises the steps of:

(c-3) computing a distance from said true position of said user to a road neighboring said true position of said user; and

(c-4) comparing said distance from said true position of said user to said road neighboring said true position of said user with a threshold, wherein said threshold is preset based on an accuracy of said integrated inertial measurement unit/global positioning system device, and said position mark of said user is displayed on said road when said distance from said true position of said user to said road neighboring said true position of said user is less than said threshold, wherein said position mark of said user is displayed at said calculated true position when said distance from said true position of said user to said road neighboring of said true position of said user is larger than said threshold.

33. An enhanced inertial measurement unit/global positioning system and map navigation process, as recited as claim 32, further comprising a step of:

feeding said true position from said time-space filtering process to said means for blending measurements from said micro IMU and said GPS receiver to further correct navigation error.

34. An enhanced inertial measurement unit/global positioning system and map navigation process, as recited as claim 30, further comprising a step of:

feeding said true position from said time-space filtering process to said means for blending measurements from said micro IMU and said GPS receiver to further correct navigation error.

35. An enhanced inertial measurement unit/global positioning system and map navigation process, as recited as claim 30, further comprising a step of performing an IMU/GPS-based primitive access process on said involved tiles, wherein said IMU/GPS-based primitive access comprises an IMU/GPS-based node access, an IMU/GPS-based edge access and an IMU/GPS-based area access, wherein said primitive includes a node, an edge and an area, wherein said node, said edge and said area in said involved tiles are retrieved.

36. An enhanced inertial measurement unit/global positioning system and map navigation process, as recited in claim 35, wherein the step (c) further comprises the steps of:

(c-1) forming a predicted position by predicting a current position of said user based on said previous position and said previous velocity of said user from said integrated inertial measurement unit/global positioning system device; and

(c-2) calculating a true position of said user based on said predicted position of said user and said measured position from said integrated inertial measurement unit/global positioning system device, wherein said true position of said user is an average position of said predicted position of said user and said measured position from said integrated inertial measurement unit/global positioning system device.

37. An enhanced inertial measurement unit/global positioning system and map navigation process, as recited in claim 36, wherein the step (c) further comprises the steps of:

(c-3) computing a distance from said true position of said user to a road neighboring said true position of said user; and

(c-4) comparing said distance from said true position of said user to said road neighboring said true position of said user with a threshold, wherein said threshold is preset based on an accuracy of said integrated inertial measurement unit/global positioning system device, and said position mark of said user is displayed on said road when said distance from said true position of said user to said road neighboring said true position of said user is less than said threshold, wherein said position mark of said user is displayed at said calculated true position when said distance from said true position of said user to said road neighboring of said true position of said user is larger than said threshold.

38. An enhanced inertial measurement unit/global positioning system and map navigation process, as recited as claim 37, further comprising a step of:

feeding said true position from said time-space filtering process to said means for blending measurements from said micro IMU and said GPS receiver to further correct navigation error.

39. An enhanced inertial measurement unit/global positioning system and map navigation process, as recited as claim 35, further comprising a step of:

feeding said true position from said time-space filtering process to said means for blending measurements from said micro IMU and said GPS receiver to further correct navigation error.

40. An enhanced inertial measurement unit/global positioning system and map navigation process, comprising steps of:

(a) receiving a measured position from an integrated inertial measurement unit/global positioning system device, wherein said integrated inertial measurement unit/global positioning system device comprises a micro IMU, a GPS receiver and means for blending measurements from said micro IMU and said GPS receiver;

(b) retrieving geospatial data from a geospatial map database based on said measured position from said integrated inertial measurement unit/global positioning system device by using a tile index file, wherein said tile index file stores geographic extent information of tiles which are geographically subdividing a coverage solely for a purpose of enhancing data management;

wherein a geographic extent of an access area is compared with said geographic extent of said tiles to derive a plurality of involved tiles for said access area;

(c) performing time-space filtering based on said measured position and said retrieved geospatial data from said geospatial map database to derive a displaying position for a user;

wherein said measured position and a previous position and a previous velocity are used to derive a true position for said user; and

(d) displaying a trajectory of said user on a graphic displaying unit, which tracks a motion of said user;

wherein the step (c) further comprises the steps of;

(c-1) forming a predicted position by predicting a current position of said user based on said previous position and said previous velocity of said user from said integrated inertial measurement unit/global positioning system device; and

(c-2) calculating a true position of said user based on said predicted position of said user and said measured position from said integrated inertial measurement unit/global positioning system device, wherein said true position of said user is an average position of said predicted position of said user and said measured position from said integrated inertial measurement unit/global positioning system device.

41. An enhanced inertial measurement unit/global positioning system and map navigation process, as recited in claim 40, wherein the step (c) further comprises the steps of:

(c-3) computing a distance from said true position of said user to a road neighboring said true position of said user; and

(c-4) comparing said distance from said true position of said user to said road neighboring said true position of said user with a threshold, wherein said threshold is preset based on an accuracy of said integrated inertial measurement unit/global positioning system device, and said position mark of said user is displayed on said road when said distance from said true position of said user to said road neighboring said true position of said user is less than said threshold, wherein said position mark of said user is displayed at said calculated true position when said distance from said true position of said user to said road neighboring of said true position of said user is larger than said threshold.

42. An enhanced inertial measurement unit/global positioning system and map navigation process, as recited as claim 41, further comprising a step of:

feeding said true position from said time-space filtering process to said means for blending measurements from said micro IMU and said GPS receiver to further correct navigation error.

43. An enhanced inertial measurement unit/global positioning system and map navigation system, comprising:

an integrated IMU/GPS device for providing a position data for a user, wherein said Integrated IMU/GPS device comprises an IMU, a GPS receiver, and means for blending measurements from said IMU and said GPS receiver;

a remote geospatial database which is stored on a remote computer system, wherein said remote computer system is connected with a computing platform via a data link;

an operational interface for providing a command input method for a user;

an integrated menu for providing a collection of functional menus for said user;

a database query and access module for providing an IMU/GPS-based efficient geospatial database access and spatial query;

a mission specific database creation module for generating a local database stored in said computing platform from said remote geospatial database;

a database updating module for adding new features using an inertial measurement unit/global positioning system device as a basic device;

a feature attribute coding catalogue for encoding for said new features added to said geospatial database and for decoding for said GPS-based efficient geospatial database access and spatial query;

a communication interface, which provides a communication link between said remote geospatial database and said computing platform;

a data uploading module for transmitting said new features added to said database to said remote geospatial database via said communication interface; and

a data downloading module for transmitting said created mission specific database from said remote geospatial database to said computing platform;

wherein said database access and query module is adapted for performing primitive access and spatial query, wherein said primitive access includes a node access, an edge access and an area access, wherein said spatial query includes a point query, a line query and an area query;

wherein said primitive access comprises the steps of;

defining an access area based on said position from said integrated inertial measurement unit/global positioning system device and an geographic extent, wherein said position from said integrated inertial measurement unit/global positioning system device is a center of said access area and said geographic extent is input by said user;

performing an IMU/GPS-based database matching process to derive an involved geospatial database, wherein said geographic extent of said access area is compared with a geographic extent of said geospatial database to check whether said access area is included in said geospatial database, intersects with said geospatial database, or excludes from said geospatial database;

performing an IMU/GPS-based involved tile finding process on said involved databases to derive involved tiles each of which is geographically subdividing a coverage solely for the purpose of enhancing data management, wherein a tile index file is used to retrieve a geographic extent of said tile, wherein said geographic extent of said access area is compared with said geographic extent of said tile to check whether said access area is included in said tile, intersects with said tile or is excluded from said tile; and

performing an IMU/GPS-based primitive access process on said involved tiles, wherein said GPS-based primitive access comprises an IMU/GPS-based node access, an IMU/GPS-based edge access, and an IMU/GPS-based area access, wherein said primitive includes a node, an edge and an area, wherein said node, said edge and said area in said involved tiles are retrieved.

44. An enhanced inertial measurement unit/global positioning system and map navigation process, as recited as claim 43, wherein said integrated IMU/GPS device comprises a micro IMU, a GPS receiver and means for blending measurements from said micro IMU and said GPS receiver, wherein a true position is obtain from a time-space filtering process is fed to said means for blending measurements from said micro IMU and said GPS receiver to further correct navigation error.

45. An enhanced inertial measurement unit/global positioning system and map navigation system, comprising:

an integrated IMU/GPS device for providing a position data for a user, wherein said Integrated IMU/GPS device comprises an IMU, a GPS receiver, and means for blending measurements from said IMU and said GPS receiver;

a remote geospatial database which is stored on a remote computer system, wherein said remote computer system is connected with a computing platform via a data link;

an operational interface for providing a command input method for a user;

an integrated menu for providing a collection of functional menus for said user;

a database query and access module for providing an IMU/GPS-based efficient geospatial database access and spatial query;

a mission specific database creation module for generating a local database stored in said computing platform from said remote geospatial database;

a database updating module for adding new features using a inertial measurement unit/global positioning system device as a basic device;

a feature attribute coding catalogue for encoding for said new features added to said geospatial database and for decoding for said GPS-based efficient geospatial database access and spatial query;

a communication interface, which provides a communication link between said remote geospatial database and said computing platform;

a data uploading module for transmitting said new features added to said database to said remote geospatial database via said communication interface; and

a data downloading module for transmitting said created mission specific database from said remote geospatial database to said computing platform;

wherein said database access and query module is adapted for performing primitive access and spatial query, wherein said primitive access includes a node access, an edge access and an area access, wherein said spatial query includes a point query, a line query and an area query;

wherein said point query comprises the steps of;

defining a query point using said operational interface on said screen;

generating a query rectangle based on said query point;

performing a geospatial database matching by comparing a geographic extent of said query rectangle with a geographic extent of said geospatial database to derive an involved geospatial database;

performing a destination tile finding by comparing said geographic extent of said query rectangle with a geographic extent of a tile of said involved geospatial database to derive an involved tile; and

performing a node spatial information retrieval on said involved tile by using a node spatial index file.

46. An enhanced inertial measurement unit/global positioning system and map navigation process, as recited as claim 45, wherein said integrated IMU/GPS device comprises a micro IMU, a GPS receiver and means for blending measurements from said micro IMU and said GPS receiver, wherein a true position is obtain from a time-space filtering process is fed to said means for blending measurements from said micro IMU and said GPS receiver to further correct navigation error.

47. An enhanced inertial measurement unit/global positioning system and map navigation system, comprising:

an integrated IMU/GPS device for providing a position data for a user, wherein said Integrated IMU/GPS device comprises an IMU, a GPS receiver, and means for blending measurements from said IMU and said GPS receiver;

a remote geospatial database which is stored on a remote computer system, wherein said remote computer system is connected with a computing platform via a data link;

an operational interface for providing a command input method for a user;

an integrated menu for providing a collection of functional menus for said user;

a database query and access module for providing an IMU/GPS-based efficient geospatial database access and spatial query;

a mission specific database creation module for generating a local database stored in said computing platform from said remote geospatial database;

a database updating module for adding new features using an inertial measurement unit/global positioning system device as a basic device;

a feature attribute coding catalogue for encoding for said new features added to said geospatial database and for decoding for said GPS-based efficient geospatial database access and spatial query;

a communication interface, which provides a communication link between said remote geospatial database and said computing platform;

a data uploading module for transmitting said new features added to said database to said remote geospatial database via said communication interface; and

a data downloading module for transmitting said created mission specific database from said remote geospatial database to said computing platform;

wherein said database access and query module is adapted for performing primitive access and spatial query, wherein said primitive access includes a node access, an edge access and an area access, wherein said spatial query includes a point query, a line query and an area query;

wherein said line query comprises the steps of;

defining a query point by pointing a line of interest using said operational interface on said screen;

generating a query rectangle based on said query point;

performing a geospatial database matching by comparing a geographic extent of said query rectangle with a geographic extent of said geospatial database to derive an involved geospatial database;

performing a destination tile finding by comparing said geographic extent of said query rectangle with a geographic extent of a tile of said involved geospatial database to derive an involved tile; and

performing an edge spatial information retrieval on said involved tile by using an edge spatial index file.

48. An enhanced inertial measurement unit/global positioning system and map navigation process, as recited as claim 47, wherein said integrated IMU/GPS device comprises a micro IMU, a GPS receiver and means for blending measurements from said micro IMU and said GPS receiver, wherein a true position is obtain from a time-space filtering process is fed to said means for blending measurements from said micro IMU and said GPS receiver to further correct navigation error.

49. An enhanced inertial measurement unit/global positioning system and map navigation system, comprising:

an integrated IMU/GPS device for providing a position data for a user, wherein said Integrated IMU/GPS device comprises an IMU, a GPS receiver, and means for blending measurements from said IMU and said GPS receiver;

a remote geospatial database which is stored on a remote computer system, wherein said remote computer system is connected with a computing platform via a data link;

an operational interface for providing a command input method for a user;

an integrated menu for providing a collection of functional menus for said user;

a database query and access module for providing an IMU/GPS-based efficient geospatial database access and spatial query;

a mission specific database creation module for generating a local database stored in said computing platform from said remote geospatial database;

a database updating module for adding new features using an inertial measurement unit/global positioning system device as a basic device;

a feature attribute coding catalogue for encoding for said new features added to said geospatial database and for decoding for said GPS-based efficient geospatial database access and spatial query;

a communication interface, which provides a communication link between said remote geospatial database and said computing platform;

a data uploading module for transmitting said new features added to said database to said remote geospatial database via said communication interface; and

a data downloading module for transmitting said created mission specific database from said remote geospatial database to said computing platform;

wherein said database access and query module is adapted for performing primitive access and spatial query, wherein said primitive access includes a node access, an edge access and an area access, wherein said spatial query includes a point query, a line query and an area query;

wherein said area query comprises the steps of;

defining a query point by pointing an area of interest using said operational interface on said screen;

generating a query rectangle based on said query point;

performing a geospatial database matching by comparing a geographic extent of said query rectangle with a geographic extent of said geospatial database to derive an involved geospatial database;

performing a destination tile finding by comparing said geographic extent of said query rectangle with a geographic extent of a tile of said involved geospatial database to derive an involved tile; and

performing an area spatial information retrieval on said involved tile by using an area spatial index file.

50. An enhanced inertial measurement unit/global positioning system and map navigation process, as recited as claim 49, wherein said integrated IMU/GPS device comprises a micro IMU, a GPS receiver and means for blending measurements from said micro IMU and said GPS receiver, wherein a true position is obtain from a time-space filtering process is fed to said means for blending measurements from said micro IMU and said GPS receiver to further correct navigation error.

51. An enhanced inertial measurement unit/global positioning system and map navigation system, comprising:

an integrated IMU/GPS device for providing a position data for a user, wherein said Integrated IMU/GPS device comprises an IMU, a GPS receiver, and a means for blending measurements from said IMU and said GPS receiver;

a geospatial database which is stored on a computing platform and provides a spatial information for a user;

an operational interface for providing a command input method for said user;

an integrated menu for providing a collection of functional menus for said user;

a database query and access module, which provides an IMU/GPS-based efficient geospatial database access and spatial query;

a database updating module for adding new features using a inertial measurement unit/global positioning system device as a basic device;

a feature attribute coding catalogue for encoding for new features added to said geospatial database and for decoding for said efficient database access and query;

a map viewer for displaying a map and a user mark on a screen, for displaying a trajectory of a motion of said user, and for zooming in and zooming out display of said geospatial data, wherein said map is generated from retrieved geospatial data in said database access and query module and displayed as background and said user mark is displayed on said screen to show a position of said user; and

a time-space filtering module for fully fusing an IMU/GPS position from said integrated inertial measurement unit/global positioning system device and said retrieved geospatial data in said database query and access module to derive an accurate position of said user;

wherein said database access and query module is adapted for performing primitive access and spatial query, wherein said primitive access includes a node access, an edge access and an area access, wherein said spatial query includes a point query, a line query and an area query;

wherein said primitive access comprises the steps of;

defining an access area based on said position from said integrated inertial measurement unit/global positioning system device and an geographic extent, wherein said position from said integrated inertial measurement unit/global positioning system device is a center of said access area and said geographic extent is input by said user;

performing an IMU/GPS-based database matching process to derive an involved geospatial database, wherein said geographic extent of said access area is compared with a geographic extent of said geospatial database to check whether said access area is included in said geospatial database, intersects with said geospatial database or is excluded from said geospatial database;

performing an IMU/GPS-based involved tile finding process on said involved databases to derive involved tiles each of which is geographically subdividing a coverage solely for the purpose of enhancing data management, wherein a tile index file is used to retrieve a geographic extent of said tile, wherein said geographic extent of said access area is compared with said geographic extent of said tile to check whether said access area is included in said tile, intersects with said tile or is excluded from said tile; and

performing an IMU/GPS-based primitive access process on said involved tiles, wherein said GPS-based primitive access comprises an IMU/GPS-based node access, an IMU/GPS-based edge access and an IMU/GPS-based area access, wherein said primitive includes a node, an edge and an area, wherein said node, said edge and said area in said involved tiles are retrieved.

52. An enhanced inertial measurement unit/global positioning system and map navigation process, as recited as claim 51, wherein said integrated IMU/GPS device comprises a micro IMU, a GPS receiver and means for blending measurements from said micro IMU and said GPS receiver, wherein a true position is obtain from a time-space filtering process is fed to said means for blending measurements from said micro IMU and said GPS receiver to further correct navigation error.

53. An enhanced inertial measurement unit/global positioning system and map navigation system, comprising:

an integrated IMU/GPS device for providing a position data for a user, wherein said Integrated IMU/GPS device comprises an IMU, a GPS receiver, and a means for blending measurements from said IMU and said GPS receiver;

a geospatial database which is stored on a computing platform and provides a spatial information for a user;

an operational interface for providing a command input method for said user;

an integrated menu for providing a collection of functional menus for said user;

a database query and access module, which provides an IMU/GPS-based efficient geospatial database access and spatial query;

a database updating module for adding new features using a inertial measurement unit/global positioning system device as a basic device;

a feature attribute coding catalogue for encoding for new features added to said geospatial database and for decoding for said efficient database access and query;

a map viewer for displaying a map and a user mark on a screen, for displaying a trajectory of a motion of said user, and for zooming in and zooming out display of said geospatial data, wherein said map is generated from retrieved geospatial data in said database access and query module and displayed as background and said user mark is displayed on said screen to show a position of said user; and

a time-space filtering module for fully fusing an IMU/GPS position from said integrated inertial measurement unit/global positioning system device and said retrieved geospatial data in said database query and access module to derive an accurate position of said user;

wherein said database access and query module is adapted for performing primitive access and spatial query, wherein said primitive access includes a node access, an edge access and an area access, wherein said spatial query includes a point query, a line query and an area query;

wherein said point query comprises the steps of;

defining a query point using said operational interface on said screen;

generating a query rectangle based on said query point;

performing a geospatial database matching by comparing a geographic extent of said query rectangle with a geographic extent of said geospatial database to derive an involved geospatial database;

performing a destination tile finding by comparing said geographic extent of said query rectangle with a geographic extent of a tile of said involved geospatial database to derive an involved tile; and

performing a node spatial information retrieval on said involved tile by using a node spatial index file.

54. An enhanced inertial measurement unit/global positioning system and map navigation process, as recited as claim 53, wherein said integrated IMU/GPS device comprises a micro IMU, a GPS receiver and means for blending measurements from said micro IMU and said GPS receiver, wherein a true position is obtain from a time-space filtering process is fed to said means for blending measurements from said micro IMU and said GPS receiver to further correct navigation error.

55. An enhanced inertial measurement unit/global positioning system and map navigation system, comprising:

an integrated IMU/GPS device for providing a position data for a user, wherein said Integrated IMU/GPS device comprises an IMU, a GPS receiver, and a means for blending measurements from said IMU and said GPS receiver;

a geospatial database which is stored on a computing platform and provides a spatial information for a user;

an operational interface for providing a command input method for said user;

an integrated menu for providing a collection of functional menus for said user;

a database query and access module, which provides an IMU/GPS-based efficient geospatial database access and spatial query;

a database updating module for adding new features using a inertial measurement unit/global positioning system device as a basic device;

a feature attribute coding catalogue for encoding for new features added to said geospatial database and for decoding for said efficient database access and query;

a map viewer for displaying a map and a user mark on a screen, for displaying a trajectory of a motion of said user, and for zooming in and zooming out display of said geospatial data, wherein said map is generated from retrieved geospatial data in said database access and query module and displayed as background and said user mark is displayed on said screen to show a position of said user; and

a time-space filtering module for fully fusing an IMU/GPS position from said integrated inertial measurement unit/global positioning system device and said retrieved geospatial data in said database query and access module to derive an accurate position of said user;

wherein said database access and query module is adapted for performing primitive access and spatial query, wherein said primitive access includes a node access, an edge access and an area access, wherein said spatial query includes a point query, a line query and an area query;

wherein said line query comprises the steps of;

defining a query point by pointing a line of interest using said operational interface on said screen;

generating a query rectangle based on said query point;

performing a geospatial database matching by comparing a geographic extent of said query rectangle with a geographic extent of said geospatial database to derive an involved geospatial database;

performing a destination tile finding by comparing said geographic extent of said query rectangle with a geographic extent of a tile of said involved geospatial database to derive an involved tile; and

performing an edge spatial information retrieval on said involved tile by using an edge spatial index file.

56. An enhanced inertial measurement unit/global positioning system and map navigation process, as recited as claim 55, wherein said integrated IMU/GPS device comprises a micro IMU, a GPS receiver and means for blending measurements from said micro IMU and said GPS receiver, wherein a true position is obtain from a time-space filtering process is fed to said means for blending measurements from said micro IMU and said GPS receiver to further correct navigation error.

57. An enhanced inertial measurement unit/global positioning system and map navigation system, comprising:

an integrated IMU/GPS device for providing a position data for a user, wherein said Integrated IMU/GPS device comprises an IMU, a GPS receiver, and a means for blending measurements from said IMU and said GPS receiver;

a geospatial database which is stored on a computing platform and provides a spatial information for a user;

an operational interface for providing a command input method for said user;

an integrated menu for providing a collection of functional menus for said user;

a database query and access module, which provides an IMU/GPS-based efficient geospatial database access and spatial query;

a database updating module for adding new features using a inertial measurement unit/global positioning system device as a basic device;

a feature attribute coding catalogue for encoding for new features added to said geospatial database and for decoding for said efficient database access and query;

a map viewer for displaying a map and a user mark on a screen, for displaying a trajectory of a motion of said user, and for zooming in and zooming out display of said geospatial data, wherein said map is generated from retrieved geospatial data in said database access and query module and displayed as background and said user mark is displayed on said screen to show a position of said user; and

a time-space filtering module for fully fusing an IMU/GPS position from said integrated inertial measurement unit/global positioning system device and said retrieved geospatial data in said database query and access module to derive an accurate position of said user;

wherein said database access and query module is adapted for performing primitive access and spatial query, wherein said primitive access includes a node access, an edge access and an area access, wherein said spatial query includes a point query, a line query and an area query;

wherein said area query comprises the steps of;

defining a query point by pointing an area of interest using said operational interface on said screen;

generating a query rectangle based on said query point;

performing a geospatial database matching by comparing a geographic extent of said query rectangle with a geographic extent of said geospatial database to derive an involved geospatial database;

performing a destination tile finding by comparing said geographic extent of said query rectangle with a geographic extent of a tile of said involved geospatial database to derive an involved tile; and

performing an area spatial information retrieval on said involved tile by using an area spatial index file.

58. An enhanced inertial measurement unit/global positioning system and map navigation process, as recited as claim 57, wherein said integrated IMU/GPS device comprises a micro IMU, a GPS receiver and means for blending measurements from said micro IMU and said GPS receiver, wherein a true position is obtain from a time-space filtering process is fed to said means for blending measurements from said micro IMU and said GPS receiver to further correct navigation error.