Pose tracking an augmented reality device

Patent metadata

Field	Value
Publication number	US-9495801-B2
Application number	US-201414267711-A
Country	US
Kind code	B2
Filing date	May 1, 2014
Priority date	May 1, 2014
Publication date	Nov 15, 2016
Grant date	Nov 15, 2016

Abstract

An augmented reality device including a plurality of sensors configured to output pose information indicating a pose of the augmented reality device. The augmented reality device further includes a band-agnostic filter and a band-specific filter. The band-specific filter includes an error correction algorithm configured to receive pose information as filtered by the band-agnostic filter and reduce a tracking error of the pose information in a selected frequency band. The augmented reality device further includes a display engine configured to position a virtual object on a see-through display as a function of the pose information as filtered by the band-agnostic filter and the band-specific filter.

First claim

The invention claimed is:

1. An augmented reality device, comprising:
a plurality of sensors configured to output pose information indicating a pose of the augmented reality device;
a band-agnostic filter configured to receive pose information from the plurality of sensors and to reduce an all-band tracking error characterized by an entire frequency band of the pose information;
a band-specific filter configured to receive pose information as filtered by the band-agnostic filter, the band-specific filter configured to reduce a tracking error of the pose information in a selected frequency band that is less than the entire frequency band; and
a display engine configured to position a virtual object on a see-through display as a function of the pose information as filtered by the band-agnostic filter and the band-specific filter.

2. The augmented reality device of claim 1 , wherein the plurality of sensors include one or more of a gyroscope, a magnetometer, an accelerometer, and an image sensor.

3. The augmented reality device of claim 1 , wherein the band-agnostic filter uses a sensor fusion algorithm configured to:
receive the pose information from each of the plurality of sensors;
combine the pose information from each of the plurality of sensors; and
reduce the all-band tracking error of the combined pose information.

4. The sensor fusion algorithm of claim 3 , wherein the sensor fusion algorithm is configured to reduce a root-mean-square tracking error of the pose information.

5. The augmented reality device of claim 1 , wherein the band-agnostic filter uses an Extended Kalman filter.

6. The augmented reality device of claim 1 , wherein the band-specific filter uses a transfer function algorithm configured to:
receive pose information as filtered by the band-agnostic filter;
transfer the tracking error of the received pose information of the pose information from a time domain to a frequency domain; and
reduce the tracking error of the pose information within the selected frequency band.

7. The augmented reality device of claim 1 , wherein the band-specific filter uses an Extended Kalman filter.

8. The augmented reality device of claim 1 , wherein the band-specific filter uses a time constant to define the selected frequency band.

9. A method of augmented reality comprising:
receiving pose information from a plurality of sensors;
processing the pose information with a band-agnostic filter configured to reduce an all-band tracking error characterized by an entire frequency band of the pose information;
processing the pose information from the band-agnostic filter with a band-specific filter configured to reduce a tracking error of the pose information in a selected frequency band that is less than the entire frequency band; and
displaying a virtual object on a see-through display, such that the position of the virtual object on the see-through display is a function of the pose information as filtered by the band-agnostic filter and the band-specific filter.

10. The method of augmented reality of claim 9 , wherein the band-agnostic filter includes a sensor fusion algorithm configured to:
receive the pose information from each of the plurality of sensors;
combine the pose information from each of the plurality of sensors; and
reduce the all-band tracking error of the combined pose information.

11. The method of claim 10 , wherein the sensor fusion algorithm is configured to reduce a root-mean-square tracking error of the pose information.

12. The method of augmented reality of claim 9 , wherein the band-agnostic filter includes an Extended Kalman filter.

13. The method of augmented reality of claim 9 , wherein the band-specific filter includes a transfer function algorithm configured to:
receive pose information as filtered by the band-agnostic filter;
transfer the tracking error of the pose information from a time domain to a frequency domain; and
reduce the tracking error of the pose information within the selected frequency band.

14. The method of augmented reality of claim 9 , wherein the band-specific filter includes an Extended Kalman filter.

15. The method of augmented reality of claim 9 , wherein the band-specific filter includes an error correction algorithm uses a time constant to define the selected frequency band.

16. A head-mounted display device comprising:
a wearable see-through display;
a plurality of sensors configured to output pose information indicating a tracked pose of the head-mounted display device; and
a display engine configured to position a virtual object on a see-through display as a function of the tracked pose of the head-mounted display device such that a perceived positional difference between the virtual object and a real-world object viewed through the see-though display is filtered by a two stage filter including a band-agnostic filter configured to reduce an all-band tracking error characterized by an entire frequency band of the pose information and a band-specific filter configured to receive filtered pose information from the band-agnostic filter and reduce a tracking error of the filtered pose information in a specified frequency band that is less than the entire frequency band.

17. The head-mounted display device of claim 16 , wherein the display engine uses a first, band-agnostic Extended Kalman filter and a second, band-specific Extended Kalman filter.

18. The head-mounted display device of claim 16 , wherein the plurality of sensors include one or more of a gyroscope, a magnetometer, an accelerometer, and an image sensor.

Assignees

• Microsoft Technology Licensing Llc

Inventors

• Ebstyne Michael John
• Schaffalitzky Frederik
• Steedly Drew
• Chan Calvin
• Eade Ethan
• Kipman Alex
• Klein Georg

Classifications

• G06F3/012 Primary

  Head tracking input arrangements · CPC title

• G06T19/006 Primary

  Mixed reality (object pose determination, tracking or camera calibration for mixed reality G06T7/00) · CPC title

• G06F3/011

  Arrangements for interaction with the human body, e.g. for user immersion in virtual reality (blind teaching G09B21/00) · CPC title

• G06F3/038

  Control and interface arrangements therefor, e.g. drivers or device-embedded control circuitry · CPC title

• G02B2027/0178

  Eyeglass type (eyeglass details G02C) · CPC title