System and method for locating, tracking, and/or monitoring the status of personnel and/or assets both indoors and outdoors

• US 9,448,072 B2
• Filed: 08/06/2008
• Issued: 09/20/2016
• Est. Priority Date: 05/31/2007
• Status: Active Grant

• Current Assignee: TRX Systems, Inc.
• Original Assignee: TRX Systems, Inc.
• Inventors: Bandyopadhyay, Amrit, Hakim, Daniel, Funk, Benjamin E., Kohn, Eric Asher, Teolis, Carole A., Blankenship, Gilmer
• Primary Examiner(s): MOYER, DALE S
• Application Number:
  US12/187,067
• Publication Number:
  US 20090043504A1
• Time in Patent Office: 2,967 Days
• Field of Search: 340/539.13, 340/573.1, 340/686.1, 342/357.12, 342/357.32, 342/357.51, 342/357.52, 342/357.54, 342/357.55, 342/357.74, 4554561-457, 701/29, 701/207, 701/213, 701/220, 701/300, 701/434, 701/467, 701/494, 701500-512, 702150-155
• US Class Current: 1/1
• CPC Class Codes: G01C 17/38 Testing, calibrating, or compensating of compasses
• CPC Class Codes: G01C 21/1652 with ranging devices, e.g. LIDAR or RADAR
• CPC Class Codes: G01C 21/1654 with electromagnetic compass
• CPC Class Codes: G01C 21/188 for accumulated errors, e.g. by coupling inertial systems with absolute positioning systems
• CPC Class Codes: G01C 21/206 specially adapted for indoor navigation
• CPC Class Codes: G01C 21/3438 Rendez-vous, i.e. searching a destination where several users can meet, and the routes to this destination for these users; Ride sharing, i.e. searching a route such that at least two users can share a vehicle for at least part of the route
• CPC Class Codes: G01C 21/3626 Details of the output of route guidance instructions traffic control systems for road vehicles involving transmission of navigation instructions to the vehicle G08G1/0968
• CPC Class Codes: G01S 19/48 by combining or switching between position solutions derived from the satellite radio beacon positioning system and position solutions derived from a further system
• CPC Class Codes: G01S 19/49 whereby the further system is an inertial position system, e.g. loosely-coupled
• CPC Class Codes: G01S 5/015 between indoor and outdoor environments
• CPC Class Codes: G01S 5/0294 Trajectory determination or predictive filtering, e.g. target tracking or Kalman filtering
• CPC Class Codes: H04W 4/021 Services related to particular areas, e.g. point of interest [POI] services, venue services or geofences
• CPC Class Codes: H04W 4/029 Location-based management or tracking services
• CPC Class Codes: H04W 4/33 for indoor environments, e.g. buildings
• CPC Class Codes: H04W 64/00 Locating users or terminals or network equipment for network management purposes, e.g. mobility management

Abstract

A system and method for locating, tracking, and/or monitoring the status of personnel and/or assets (collectively “trackees”), both indoors and outdoors, is provided. Tracking data obtained from any number of sources utilizing any number of tracking methods (e.g., inertial navigation and signal-based methods) may be provided as input to a mapping application. The mapping application may generate position estimates for trackees using a suite of mapping tools to make corrections to the tracking data. The mapping application may further use information from building data, when available, to enhance position estimates. Indoor tracking methods including, for example, sensor fusion methods, map matching methods, and map building methods may be implemented to take tracking data from one or more trackees and compute a more accurate tracking estimate for each trackee. Outdoor tracking methods may be implemented to enhance outdoor tracking data by combining tracking estimates such as inertial tracks with magnetic and/or compass data if and when available, and with GPS, if and when available.

Claims

1. A computer-implemented method of generating position estimates of a trackee at a location, the method being implemented by a computer that includes a physical processor, the method, comprising:

obtaining, as input, tracking data for the trackee obtained from inertial sensors, wherein the tracking data includes a collection of tracking points forming a tracking path of the trackee, and wherein each tracking point includes at least two-dimensional location coordinates;

causing a map of the location to be displayed, via a graphical user interface associated with the computer, the map including one or more building features;

generating position estimates for the trackee by dividing the tracking path into polygonal path segments of tracking points and correlating a polygonal path segment to a building feature to reduce tracking errors associated with the inertial sensors responsive to a determination that the polygonal path segment matches the building feature; and

causing the generated position estimates to be displayed on the map.

2. The method of claim 1, wherein the obtained tracking data comprises previously-acquired, stored tracking data.

3. The method of claim 1, wherein one or more of the polygonal path segments include rectangular segments comprising:

a group of tracking points contained within a bounding box having a threshold maximum width.

4. The method of claim 1, further comprising:

identifying polygonal path segments, having a length that exceeds a predetermined threshold, that are approximately parallel or perpendicular to one another as being on a path grid;

correcting the identified polygonal path segments to a relative grid to eliminate error accumulated by the inertial sensors; and

matching the path grid to one or more building features.

5. The method of claim 1, wherein the tracking data includes tracking data obtained from a gyroscope and a compass, the method further comprising:

selecting a polygonal path segment comprising a series of tracking points;

determining a compass prediction for a heading of the selected polygonal path segment, using each tracking point in the series of tracking points, by rotating a compass angle obtained from the compass at each tracking point by the difference between the polygonal path segment heading and a gyroscope angle for the tracking point;

clustering compass-gyroscope correlated heading estimates for the polygonal path segment heading; and

determining a highest probability compass heading for the polygonal path segment heading using the clustered compass-gyroscope correlated heading estimates.

6. The method of claim 1, wherein the tracking data includes tracking data obtained from a compass, the method further comprising:

determining building grid angles from the one or more building features; and

clustering compass angles of tracking points forming at least one polygonal path segment around grid angle headings to determine the highest probability grid heading for the at least one polygonal path segment, wherein the compass angles are obtained from the compass.

7. The method of claim 1, further comprising:

determining grid angles and partitions for a building from the one or more building features;

identifying, for a selected polygonal path segment, a building partition that the polygonal path segment crosses or lies within; and

implementing a correction by rotating the polygonal path segment to a probable heading based on a grid angle associated with the identified building partition responsive to a determination that the correction is within determined correction bounds.

8. The method of claim 1, further comprising:

determining grid angles and partitions for a building from the one or more building features;

detecting path grids;

associating the polygonal path segments and the path grids with compass angles and grid angles by clustering and building partition testing; and

aligning the polygonal path segments and path grids to the building grid angles.

9. The method of claim 1, wherein the map of the location comprises a building floor plan.

10. A system for generating position estimates of a trackee at a location, the system comprising:

a computer processor configured to;

obtain, as input, tracking data for the trackee obtained from inertial sensors, wherein the tracking data includes a collection of tracking points forming a tracking path of the trackee, and wherein each tracking point includes at least two-dimensional location coordinates;

cause a map of the location to be displayed, via a graphical user interface, the map including one or more building features;

generate position estimates for the trackee by dividing the tracking path into polygonal path segments of tracking points and correlating a polygonal path segment to a building feature to reduce tracking errors associated with the inertial sensors responsive to a determination that the polygonal path segment matches the building feature; and

cause the generated position estimates to be displayed on the map.

11. The system of claim 10, wherein the obtained tracking data comprises previously-acquired, stored tracking data.

12. The system of claim 10, wherein one or more of the polygonal path segments include rectangular segments comprising a group of tracking points contained within a bounding box having a threshold maximum width.

13. The system of claim 10, wherein the computer processor is further configured to:

identify polygonal path segments, having a length that exceeds a predetermined threshold, that are approximately parallel or perpendicular to one another as being on a path grid;

correct the identified polygonal path segments to a relative grid to eliminate error accumulated by the inertial sensors; and

match the path grid to one or more building features.

14. The system of claim 10, wherein the tracking data includes tracking data obtained from a gyroscope and a compass, and wherein the computer processor is further configured to:

select a polygonal path segment comprising a series of tracking points;

determine a compass prediction for a heading of the selected polygonal path segment, using each tracking point in the series of tracking points, by rotating a compass angle obtained from the compass at each tracking point by the difference between the polygonal path segment heading and a gyroscope angle obtained from the gyroscope for the tracking point;

cluster compass-gyroscope correlated heading estimates for the polygonal path segment heading; and

determine a highest probability compass heading for the polygonal path segment heading using the clustered compass-gyroscope correlated heading estimates.

15. The system of claim 10, wherein the tracking data includes tracking data obtained from a compass, and wherein the computer processor is further configured to:

determine building grid angles from the one or more building features; and

cluster compass angles of tracking points forming at least one polygonal path segment around grid angle headings to determine the highest probability grid heading for the at least one polygonal path segment, wherein the compass angles are obtained from the compass.

16. The system of claim 10, wherein the computer processor is further configured to:

determine grid angles and partitions for a building from the one or more building features;

identify, for a selected polygonal path segment, a building partition that the polygonal path segment crosses or lies within; and

implement a correction by rotating the polygonal path segment to a probable heading based on a grid angle associated with the identified building partition responsive to a determination that the correction is within determined correction bounds.

17. The system of claim 10, wherein the computer processor is further configured to:

determine grid angles and partitions for a building from the one or more building features;

detect path grids;

associate the polygonal path segments and the path grids with compass angles and grid angles by clustering and building partition testing; and

align the polygonal path segments and path grids to the building grid angles.

18. The system of claim 10, wherein the map of the location comprises a building floor plan.

19. A non-transitory computer readable storage medium comprising executable code for generating position estimates of a trackee at a location, the computer executable code, when executed by a processor, causing the processor to:

obtain, as input, tracking data for the trackee obtained from inertial sensors, wherein the tracking data includes a collection of tracking points forming a tracking path of the trackee, and wherein each tracking point includes at least two-dimensional location coordinates;

cause a map of the location to be displayed, via a graphical user interface, the map including one or more building features;

generate position estimates for the trackee by dividing the tracking path into polygonal path segments of tracking points and correlating a polygonal path segment to a building feature to reduce tracking errors associated with the inertial sensors responsive to a determination that the polygonal path segment matches the building feature; and

cause the generated position estimates to be displayed on the map.