MULTIPLE DATA SOURCES PEDESTRIAN NAVIGATION SYSTEM

• US 20130238237A1
• Filed: 10/09/2011
• Published: 09/12/2013
• Est. Priority Date: 10/13/2010
• Status: Abandoned Application

• Current Assignee: Elbit Systems Limited
• Original Assignee: Elbit Systems Limited
• Inventors: Efrat, Ilan, Abramson Liani, Ari, Leizerson, Ilya
• Application Number:
  US13/878,756
• Publication Number:
  US 20130238237A1
• Time in Patent Office: Days
• US Class Current: 701/445
• CPC Class Codes: G01C 21/12 executed aboard the object being navigated; Dead reckoning
• CPC Class Codes: G01C 21/1654 with electromagnetic compass
• CPC Class Codes: G01C 25/005 initial alignment, calibration or starting-up of inertial devices
• CPC Class Codes: G01S 19/49 whereby the further system is an inertial position system, e.g. loosely-coupled

Abstract

A method of pedestrian navigation, based on an external positioning system and a Dead Reckoning (DR) system is provided herein. The method may employ the following steps: obtaining external positioning readings from an external positioning source and DR position readings from a pedestrian-carried platform; estimating an external positioning error, based at least partially on the external positioning and the DR position readings; and applying an estimation function to the external position readings, the DR position readings, and the external positioning errors, to yield a corrected estimated position.

Claims

1. A method of pedestrian navigation based on an external positioning system and a Dead Reckoning (DR) system, the method comprising:

obtaining external position readings from a remote external source, and DR position readings from a pedestrian-carried platform;

estimating an external positioning source error, based at least partially on the external position readings and the DR position readings; and

applying an estimation function to the external position readings, the DR position readings, and the external positioning source error, to yield a corrected estimated position.

2. The method according to claim 1, wherein the external positioning system comprises at least one of:

Global Positioning System (GPS), manual position fix, and position fix associated with a source independent of the pedestrian-carried platform.

3. The method according to claim 1, further comprising:

deriving pedestrian-eligible positions from a terrain/floor plan database and estimating external positioning source error or DR error based on the pedestrian-eligible positions, wherein the estimation function is further applied to the estimated external positioning source error or the estimated DR error to yield an improved corrected estimated position.

4. The method according to claim 1, further comprising:

deriving pedestrian-eligible positions from a terrain/floor plan database, wherein the estimation function is further applied to the pedestrian-eligible positions to yield an improved corrected estimated position.

5. The method according to claim 1, further comprising:

recording a sequence of bodily movements; and

analyzing the recorded sequence to yield calibration data associated with magnetic characteristics of the bodily environment, useable for the DR system.

6. The method according to claim 1, further comprising:

recording a sequence of bodily movements; and

analyzing the recorded sequence to yield alignment or orientation data associated with orientation or alignment respectively of the DR system on the body, useable for determining direction of advancement of the pedestrian.

7. A method for calibrating a pedestrian-carried Dead Reckoning (DR) system comprising:

recording a sequence of bodily movements; and

analyzing the sequence to yield at least one of;

calibration data associated with magnetic characteristics of the bodily environment and alignment or orientation data associated with alignment or orientation respectively of the DR system on the body, wherein the calibration data is useable for calibration of the DR system and wherein the alignment or orientation data is useable for determining direction of advancement of the pedestrian.

8. A system for pedestrian navigation comprising:

an external positioning system;

a Dead Reckoning (DR) system;

an external positioning error estimation module; and

a corrected position estimation module,

wherein the external positioning error estimation module is configured to;

obtain external positioning and DR position readings from the external positioning and the DR systems located on a pedestrian-carried platform, wherein the external positioning reading is provided remotely; and

estimate an external positioning error, based at least partially on the external positioning and the DR position readings, and

wherein the corrected position estimation module applies an estimation function to the external positioning readings, the DR position readings, and the external positioning error, to yield a corrected estimated position.

9. The system according to claim 8, further comprising a terrain/floor plan database and a DR error estimation module, wherein the external positioning error estimation module and the DR error estimation module are configured to derive pedestrian-eligible positions from the terrain/floor plan database and estimate external positioning errors or DR errors respectively, based on the pedestrian-eligible positions, wherein the estimation function is further applied by the corrected position estimated module to the estimated external positioning errors or the estimated DR errors respectively, to yield an improved corrected estimated position.

10. The system according to claim 8 or 9, wherein the external positioning system comprises at least one of:

Global Positioning System (GPS), manual position fix, and position fix associated with a source independent of the pedestrian-carried platform.

11. The system according to claim 8, further comprising a terrain/floor plan database containing pedestrian-eligible positions, wherein the estimation function is further applied to the pedestrian-eligible positions, by the corrected position estimated module, to yield an improved corrected estimated position.

12. The system according to claim 8, further comprising a calibration module, wherein the calibration module is configured to recorde a sequence of bodily movements and analyze the recorded sequence of bodily movements, to yield calibration data associated with magnetic characteristics of the bodily environment, useable for the DR system.

13. The system according to claim 8, further comprising an alignment module, wherein the alignment module is configured to record a sequence of bodily movements and analyze the compared sequence, to yield alignment or orientation data associated with alignment or orientation of the DR system respectively on the body, useable for determining direction of advancement of the pedestrian.

14. A pedestrian navigation system comprising:

A Dead reckoning (DR) system;

a terrain/floor plan database;

a DR error estimation module; and

a corrected position estimation module,

wherein the DR system is configured to generate DR position readings,

wherein the DR error estimation module is configured to derive pedestrian-eligible positions from the terrain/floor plan database and estimate external DR errors based on the pedestrian-eligible positions and the DR position readings,

wherein the corrected position estimation module is configured to apply an estimation function to the DR position readings and the estimated DR errors respectively, to yield an improved corrected estimated position.

15. A system for calibrating a pedestrian-carried Dead Reckoning (DR) system comprising:

a DR module configured to generate DR position readings;

sensors configured to record a sequence of bodily movements;

analyzing module configured to analyze the recorded sequence to yield at least one of;

calibration data associated with magnetic characteristics of the bodily environment and alignment or orientation data associated with alignment or orientation respectively of the DR system on the body, wherein the calibration data is useable for calibration of the DR system and wherein the alignment or orientation data is useable for determining direction of advancement of the pedestrian.

16. The system according to claim 15, wherein the analyzing module is further configured to yield an updated calibration data associated with the magnetic characteristics of the bodily environment based on repeated momentary readings of at least one of:

magnetic field strength and magnetic field directions.