System and method for advanced 3D visualization for mobile navigation units

• US 20040128070A1
• Filed: 12/31/2002
• Published: 07/01/2004
• Est. Priority Date: 12/31/2002
• Status: Active Grant

• Current Assignee: Robert Bosch Corporation (Robert Bosch GmbH), Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Schmidt, Hauke, Lee, Aaron, Chen, Tuolin
• Granted Patent: US 6,885,939 B2
• Time in Patent Office: Days
• US Class Current: 701/211
• CPC Class Codes: G01C 21/3638 including 3D objects and buildings three dimensional [3D] modelling, e.g. data description of 3D objects G06T17/00; geographic models G06T17/05
• CPC Class Codes: G06F 16/29 Geographical information databases
• CPC Class Codes: G06F 16/9577 Optimising the visualization of content, e.g. distillation of HTML documents
• CPC Class Codes: G06T 17/05 Geographic models
• CPC Class Codes: G06T 2210/61 Scene description
• CPC Class Codes: G09B 29/10 Map spot or coordinate position indicators; Map reading aids optical projection apparatus per se G03B

Abstract

A system providing three-dimensional visual navigation for a mobile unit includes a location calculation unit for calculating an instantaneous position of the mobile unit, a viewpoint control unit for determining a viewing frustum from the instantaneous position, a scenegraph manager in communication with at least one geo-database to obtain geographic object data associated with the viewing frustum and generating a scenegraph organizing the geographic object data, and a scenegraph renderer which graphically renders the scenegraph in real time. To enhance depiction, a method for blending images of different resolutions in the scenegraph reduces abrupt changes as the mobile unit moves relative to the depicted geographic objects. Data structures for storage and run-time access of information regarding the geographic object data permit on-demand loading of the data based on the viewing frustum and allow the navigational system to dynamically load, on-demand, only those objects that are visible to the user.

Claims

1. A system for providing three-dimension visual navigation for a mobile unit:

a location calculation unit for calculating an instantaneous position of the mobile unit;

a viewpoint control unit for determining a viewing frustum based on the position of the mobile unit;

a scenegraph manager in communication with at least one geo-database, the scenegraph manager obtaining geographic object data associated with the viewing frustum from the at least one geo-database and generating a scenegraph that organizes the obtained geographic object data; and

a scenegraph renderer for graphically rendering the scenegraph as a three-dimensional depiction in real time.

2. The system of claim 1, wherein the location calculation unit further calculates an instantaneous orientation of the mobile unit.

3. The system of claim 2, further comprising:

a route calculation module including information associated with a selected route, the route calculation module providing route information to the viewpoint control unit such that the viewpoint control unit can, in a preview operating mode, modify the viewing frustum based upon the route information.

4. The system of claim 2, further comprising:

a position sensor; and

an orientation sensor;

wherein the location calculation unit calculates the position and orientation of the mobile unit based on signals generated at the position sensor and the orientation sensor.

5. The system of claim 4, wherein the position sensor includes a GPS receiver.

6. The system of claim 5, wherein the position sensor includes an inertial sensor device.

7. The system of claim 2, further comprising:

a user input module, the user input module providing user selections to the viewpoint control unit for altering an operation of the viewpoint control unit.

8. The system of claim 7, wherein the viewpoint control unit determines the viewing frustum according to one of the following selectable viewing modes:

(a) a helicopter view;

(b) the viewpoint location matches the position of the mobile unit; and

(c) the viewpoint location and orientation matches the position and orientation of the mobile unit.

9. The system of claim 1, wherein the scenegraph includes at least one of digital roadmaps, satellite images, and digital elevation models.

10. The system of claim 9, wherein the scenegraph includes satellite images of a plurality of resolutions.

11. The system of claim 1, wherein the scenegraph manager uses a hierarchical method for on-demand loading of geographic object data, the hierarchical method employing defined data structures to efficiently access the geographic object data pertinent to the determined viewing frustum.

12. A system for providing geographic object data to a visual navigation system of a mobile unit, the system comprising:

at least one specialized geo-database, the at least one specialized geo-database storing geographic object data for enabling real-time visual navigation of a geographical region; and

a communication module, the communication module communicating with the mobile unit and providing access to stored data within the at least one geo-database.

13. The system of claim 12, wherein the at least one specialized geo-database stores at least one of satellite images, building textures, digital elevation models, and roadmap databases.

14. A system for providing three-dimension visual navigation for a mobile unit:

a location calculation unit for calculating an instantaneous position of the mobile unit;

a viewpoint control unit for determining a viewing frustum based on the position of the mobile unit;

at least one geo-database;

a scenegraph manager in communication with the at least one geo-database, the scenegraph manager obtaining geographic object data associated with the viewing frustum from the at least one geo-database and generating a scenegraph that organizes the obtained geographic object data; and

a scenegraph renderer for graphically rendering the scenegraph as a three-dimensional depiction in real time.

15. The system of claim 14, wherein the scenegraph manager uses a hierarchical method for on-demand loading of geographic object data from the at least one geo-database, the hierarchical method employing defined data structures to efficiently access the geographic object data pertinent to the determined viewing frustum.

16. The system of claim 14, further comprising:

a route calculation module including information associated with a selected route, the route calculation module providing route information to the viewpoint control unit such that the viewpoint control unit can, in a preview operating mode, modify the viewing frustum based upon the route information.

17. A method of three-dimension visual navigation in a mobile unit comprising:

calculating an instantaneous position of the mobile unit;

determining a viewing frustum based on the position of the mobile unit;

obtaining geographic object data associated with the viewing frustum from at least one geo-database;

generating a scenegraph that organizes the obtained geographic object data; and

graphically rendering the scenegraph as a three-dimensional depiction in real time.

18. The method of claim 17, further comprising:

selecting a travel route; and

modifying the viewing frustum using route information corresponding to the travel route.

19. The method of claim 17, further comprising:

calculating an instantaneous orientation of the mobile unit.

20. The method of claim 19, further comprising:

modifying the viewing frustum based on user inputs.

21. The method of claim 19, further comprising:

defining data structures to efficiently access the geographic object data pertinent to the determined viewing frustum.

22. The method of claim 19, wherein the scenegraph includes at least one of digital roadmaps, satellite images, and digital elevation models.