Deduced reckoning navigation without a constraint relationship between orientation of a sensor platform and a direction of travel of an object

• US 8,594,971 B2
• Filed: 09/22/2010
• Issued: 11/26/2013
• Est. Priority Date: 09/22/2010
• Status: Active Grant

• Current Assignee: Invensense Incorporated (TDK Corporation)
• Original Assignee: Invensense Incorporated (TDK Corporation)
• Inventors: Keal, William Kerry, Sachs, David, Lin, Shang-Hung, Anderson, Erik
• Primary Examiner(s): Kundu, Sujoy
• Assistant Examiner(s): Desta, Elias
• Application Number:
  US12/887,900
• Publication Number:
  US 20120072166A1
• Time in Patent Office: 1,161 Days
• Field of Search: 702/141, 702/142, 702/150, 700/302, 324/162, 324/163
• US Class Current: 702/150
• CPC Class Codes: G01C 21/1654 with electromagnetic compass
• CPC Class Codes: G01C 22/006 Pedometers

Abstract

Systems, methods, and apparatus for performing deduced reckoning navigation without a constraint relationship between orientation of a sensor platform and a direction of travel of an object are described herein. A sensor fusion component can be configured to receive data from sensors of a sensor platform coupled to a pedestrian; and generate world coordinate information based on the data. Further, a gait recognition component can be configured to record one or more walking patterns of the pedestrian in a training database; and determine whether the world coordinate information is associated with a walking pattern of the one or more walking patterns. Furthermore, a position estimation component can be configured to estimate a position of the pedestrian based on the world coordinate information if the world coordinate information is associated with the walking pattern, regardless of an orientation of the sensor platform with respect to the position of the pedestrian.

Claims

1. A method, comprising:

receiving signals from a sensor platform physically coupled to an object;

generating world-frame coordinate information based on the signals;

generating p-frame coordinate information based on the world-frame coordinate information;

correlating the p-frame coordinate information with profiles of the object moving with the sensor platform to obtain correlated p-frame coordinate information; and

estimating, by a system comprising a processor based on the correlated p-frame coordinate information, a direction of travel of the object irrespective of the orientation of the sensor platform relative to the object.

2. The method of claim 1, wherein the correlating comprises:

correlating the p-frame coordinate information with step profiles of a pedestrian stepping with the sensor platform in a particular location.

3. The method of claim 2, further comprising:

detecting false steps of the pedestrian in response to the correlating the p-frame coordinate information with the step profiles; and

estimating a direction of travel of the pedestrian by rejecting the false steps.

4. The method of claim 2, further comprising:

recording, over a period of time, one or more gait patterns of the pedestrian in a training database; and

generating the step profiles based on the one or more gait patterns.

5. The method of claim 2, further comprising:

utilizing a learning algorithm to generate the step profiles.

6. The method of claim 2, wherein the correlating the p-frame coordinate information with the step profiles comprises:

filtering the p-frame information to obtain filtered p-frame information; and

correlating the filtered p-frame information with the step profiles.

7. The method of claim 1, wherein the estimating comprises:

estimating the direction of travel of the object using map information.

8. The method of claim 1, further comprising:

reducing power consumption of the sensor platform in response to the estimating the direction of travel of the object.

9. The method of claim 1, further comprising:

determining a wheel revolution rate of a vehicle based on the signals.

25. The method of claim 2, further comprising:

estimating the direction of travel of the pedestrian based on the correlated p-frame coordinate information.

10. A system, comprising:

a sensor fusion component configured to;

receive data from sensors of a sensor platform coupled to a pedestrian; and

generate world coordinate information based on the data;

a gait recognition component configured to;

record one or more walking patterns of the pedestrian in a training database; and

determine whether the world coordinate information is associated with a walking pattern of the one or more walking patterns; and

a position estimation component configured to;

estimate a position of the pedestrian based on the world coordinate information in response to a determination that the world coordinate information is associated with the walking pattern, regardless of an orientation of the sensor platform with respect to the position of the pedestrian.

11. The system of claim 10, wherein the sensors comprise at least one of an inertial sensing device, a magnetic sensor, an altimeter, or a global positioning system (GPS) sensor.

12. The system of claim 10, wherein the sensor fusion component is further configured to generate, based on the data, an orientation, a linear acceleration, and an angular velocity of the sensor platform in a world coordinate system.

13. The system of claim 10, wherein the sensor fusion component combines information received from a 3-axis gyroscope and a 3-axis accelerometer to generate the world coordinate information in quaternion form.

14. The system of claim 10, wherein the position estimation component estimates, via Bayesian inference, the position of the pedestrian utilizing map information.

15. The system of claim 11, further comprising a GPS power management component configured to regulate a duty cycle of the GPS sensor based on a tracking state, a stationary state, and a learning state.

16. The system of claim 10, wherein the sensor fusion component, the gait recognition component, and the position estimation component are included in an integrated circuit.

17. The system of claim 10, wherein the sensor platform, the sensor fusion component, the gait recognition component, and the position estimation component are included in an integrated circuit.

18. The system of claim 17, wherein the integrated circuit is included in at least one of an earphone, an earring, a pen, or eye glasses.

19. The system of claim 10, wherein the position of the pedestrian is transmitted to a display device via a wireless protocol.

20. An apparatus, comprising:

means for combining information received from different sensors of a sensor platform physically coupled to an entity;

means for converting world-frame data of the combined information into p-frame data;

means for correlating the p-frame data with profiles of the entity moving with the sensor platform; and

means for estimating a direction of travel of the entity based on an output of the means for correlating the p-frame data with the profiles, irrespective of an orientation of the sensor platform with respect to the entity.

21. The apparatus of claim 20, wherein the means for correlating comprises:

means for correlating the p-frame data with step profiles of a pedestrian stepping with the sensor platform.

22. The apparatus of claim 21, wherein the means for estimating comprises:

means for estimating a direction of travel of the pedestrian based on an output of the means for correlating the p-frame data with the step profiles.

23. The apparatus of claim 20, further comprising:

means for reducing power consumption of the sensor platform based on an output of the means for estimating the direction of travel of the entity.

24. The apparatus of claim 20, further comprising:

means for determining a wheel revolution rate of a vehicle based an output of the means for combining the information.