METHOD AND APPARATUS FOR ESTIMATING 3D POSITION AND ORIENTATION THROUGH SENSOR FUSION

• US 20120330594A1
• Filed: 05/07/2012
• Published: 12/27/2012
• Est. Priority Date: 06/22/2011
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: LEE, Hyong Euk, Bang, Won Chul, CHOI, Chang Kyu, KIM, Sang Hyun
• Granted Patent: US 9,759,804 B2
• Time in Patent Office: Days
• US Class Current: 702/94
• CPC Class Codes: G01S 5/16 using electromagnetic waves other than radio waves
• CPC Class Codes: G01S 5/163 Determination of attitude using inertial means G01C9/00; control of attitude G05D1/49

Abstract

An apparatus and method for estimating a three-dimensional (3D) position and orientation based on a sensor fusion process is provided. The method of estimating the 3D position and orientation may include estimating a strength-based position and a strength-based orientation of a remote apparatus when a plurality of strength information is received, based on an attenuation characteristic of a strength that varies based on a distance and orientation, estimating an inertia-based position and an inertia-based orientation of the remote apparatus by receiving a plurality of inertial information, and estimating a fused position based on a weighted-sum of the strength-based position and the inertia-based position, and to estimate a fused orientation based on a weighted-sum of the strength-based orientation and the inertia-based orientation. The strength-based position and the strength-based orientation may be estimated based on a plurality of adjusted strength information from which noise is removed using a plurality of previous strength information.

Claims

1. An apparatus for estimating a position and an orientation, the apparatus comprising:

a strength-based estimating unit to estimate a strength-based position and a strength-based orientation of a remote apparatus when a plurality of strength information is received, based on an attenuation characteristic of a strength that varies based on a distance and an orientation;

an inertia-based estimating unit to estimate an inertia-based position and an inertia-based orientation of the remote apparatus by receiving a plurality of inertial information; and

a fusion estimating unit to estimate a fused position based on a weighted-sum of the strength-based position and the inertia-based position, and to estimate a fused orientation based on a weighted-sum of the strength-based orientation and the inertia-based orientation.

2. The apparatus of claim 1, further comprising

a raw data estimating unit to estimate a plurality of strength information based on the fused position and the fused orientation;

a noise estimating unit to estimate noise by comparing the plurality of estimated strength information and the plurality of received strength information; and

a strength adjusting unit to adjust a plurality of subsequent strength information by removing the noise, and to provide the plurality of adjusted strength information to the strength-based estimating unit,

wherein the strength-based estimating unit estimates, based on a plurality of adjusted strength information, the strength-based position and the strength-based orientation when the plurality of adjusted strength information are received.

3. The apparatus of claim 1, wherein, when the weighted-sum is calculated, the fusion estimating unit assigns a relatively higher weight to the inertia-based position and the inertia-based orientation than to the strength-based position and the strength-based orientation, as a movement speed of the remote apparatus decreases.

4. The apparatus of claim 1, wherein, when the weighted-sum is calculated, the fusion estimating unit assigns a relatively higher weight to the inertia-based position and the inertia-based orientation than to the strength-based position and the strength-based orientation, as a distance of the remote apparatus increases.

5. The apparatus of claim 1, wherein, when the movement speed of the remote apparatus is lower than a predetermined speed while the weighted-sum is calculated, the fusion estimating unit estimates the inertia-based position as the fused position, and estimates the inertia-based orientation as the fused orientation.

6. The apparatus of claim 1, wherein the inertia-based estimating unit estimates the inertia-based position and the inertia-based orientation using a variance in the plurality of inertial information based on a latest estimated fused position or a latest estimated strength-based position.

7. The apparatus of claim 6, wherein the fusion estimating unit comprises performing one of:

estimating the strength-based position and the strength-based orientation as the fused position and the fused orientation, respectively, at a point in time in which the strength-based position and the strength-based orientation exist; and

estimating the inertia-based position and the inertia-based orientation as the fused position and the fused orientation, respectively, at a point in time in which the strength-based position and the strength-based orientation are absent.

8. The apparatus of claim 1, wherein at least one of the strength-based estimating unit, the inertia-based estimating unit, and the fusion estimating unit is configured as a Kalman Filter.

9. The apparatus of claim 1, wherein the plurality of strength information corresponds to a strength of an optical signal emitted based on a predetermined wavelength or a strength of an electromagnetic field.

10. The apparatus of claim 1, wherein the plurality of inertial information includes at least one of a tri-axial acceleration, a tri-axial gravity acceleration, and a tri-axial angular velocity measured through an inertial sensor.

11. A method of estimating a position and an orientation, the method comprising:

estimating a strength-based position and a strength-based orientation of a remote apparatus when a plurality of strength information is received, using an attenuation characteristic of a strength that varies based on a distance and an orientation;

estimating an inertia-based position and an inertia-based orientation of the remote apparatus by receiving a plurality of inertial information; and

estimating a fused position by calculating a weighted-sum of the strength-based position and the inertia-based position, and estimating a fused orientation by calculating a weighted-sum of the strength-based orientation and the inertia-based orientation.

12. The method of claim 11, further comprising:

reversely estimating a plurality of strength information based on the fused position and the fused orientation;

estimating noise by comparing the plurality of estimated strength information and the plurality of received strength information; and

adjusting a plurality of subsequent strength information by removing the noise, and outputting the plurality of adjusted strength information,

wherein the estimating of the strength-based position and the strength-based orientation comprises;

estimating the strength-based position and the strength-based orientation based on a plurality of adjusted strength information.

13. The method of claim 11, wherein, when the weighted-sum is calculated, the estimating of the fused position and the fused orientation comprises assigning a relatively higher weight to the inertia-based position and the inertia-based orientation than to the strength-based position and the strength-based orientation, as a movement speed of the remote apparatus decreases.

14. The method of claim 11, wherein, when the weighted-sum is calculated, the estimating of the fused position and the fused orientation comprises assigning a relatively higher weight to the inertia-based position and the inertia-based orientation than to the strength-based position and the strength-based orientation, as a distance of the remote apparatus increases.

15. The method of claim 11, wherein, when the movement speed of the remote apparatus is lower than a predetermined speed while the weighted-sum is calculated, the estimating of the fused position and the fused orientation comprises estimating the inertia-based position as the fused position, and estimates the inertia-based orientation as the fused orientation.

16. The method of claim 11, wherein the plurality of strength information correspond to a strength of an optical signal emitted based on a predetermined wavelength or a strength of an electromagnetic field.

17. The method of claim 11, wherein the plurality of inertial information include at least one of a tri-axial acceleration, a tri-axial gravity acceleration, and a tri-axial angular velocity measured through an inertial sensor.

18. A system of estimating a position and an orientation, the system comprising:

a transmitting apparatus comprising at least two transmitting units to transmit a signal for measuring a strength;

a receiving apparatus comprising at least two receiving units to receive the signal, and to measure the strength of the signal, and outputting a plurality of strength information;

a remote apparatus comprising an inertia sensor unit to measure a plurality of inertial information, and one of the transmitting apparatus and the receiving apparatus; and

an estimating apparatus estimating a fused position and a fused orientation of the remote apparatus by fusing the plurality of strength information and the plurality of inertial information.

19. The system of claim 18, wherein the estimating apparatus comprises:

a strength-based estimating unit to estimate a strength-based position and a strength-based orientation of the remote apparatus when the plurality of strength information is received, based on an attenuation characteristic of a strength that varies based on a distance and orientation;

an inertia-based estimating unit to estimate an inertia-based position and an inertia-based orientation of the remote apparatus by receiving the plurality of inertial information; and

a fusion estimating unit to estimate the fused position based on a weighted-sum of the strength-based position and the inertia-based position, and to estimate the fused orientation based on a weighted-sum of the strength-based orientation and the inertia-based orientation.

20. The system of claim 19, wherein:

the estimating apparatus further comprises;

a raw data estimating unit to estimate a plurality of strength information based on the fused position and the fused orientation;

a noise estimating unit to estimate noise by comparing the plurality of estimated strength information and the plurality of received strength information; and

a strength adjusting unit to adjust a plurality of subsequent strength information by removing the noise, and to provide the plurality of adjusted strength information to the strength-based estimating unit,

wherein the strength-based estimating unit estimates, based on a plurality of adjusted strength information, the strength-based position and the strength-based orientation when the plurality of adjusted strength are received.

21. The system of claim 18, wherein:

at least three receiving units are included in the receiving apparatus when two transmitting units are used, and

at least two receiving units are included in the receiving apparatus when three transmitting units are used.

22. The system of claim 18, wherein the at least two transmitting units have different directionalities from each other, and a predetermined angle between the directionalities is determined in advance.

23. The system of claim 18, wherein positions and directionalities of the at least two receiving units are determined in advance.

24. The system of claim 18, wherein:

the at least two transmitting units transmit the signal based on a predetermined frequency that is robust against noise, and

the at least two receiving units receive the signal using a filter through which the predetermined frequency is able to pass.