System and method for tracking a body

Patent metadata

Field	Value
Publication number	US-11826139-B2
Application number	US-201816769741-A
Country	US
Kind code	B2
Filing date	Dec 7, 2018
Priority date	Dec 8, 2017
Publication date	Nov 28, 2023
Grant date	Nov 28, 2023

Abstract

Provided is a system, method, and apparatus for tracking a body. The method includes communicating at least one activation signal to each RF transponder of a first array and a second array, receiving a plurality of response signals from the first array and the second array, the plurality of response signals comprising a response signal for each RF transponder of the first array and the second array, determining a difference in distances between the antenna and each RF transponder of the first array and each transponder of the second array based at least partially on at least one corresponding response signal of the plurality of response signals, and determining a relative location of the first portion of the body and the second portion of the body.

First claim

The invention claimed is:

1. A method for tracking a body comprising a plurality of arrays of radio frequency (RF) transponders arranged thereon, the plurality of arrays comprising a first array of RF transponders arranged on a first portion of the body and a second array of RF transponders arranged on a second portion of the body, the first portion of the body and the second portion of the body connecting at a first joint of the body such that the first array and the second array are separated by the first joint, the method comprising:
communicating, with an antenna of a reader device, at least one activation signal to each RF transponder of the first array and the second array;
receiving, with the antenna, a plurality of response signals from the first array and the second array, the plurality of response signals comprising a response signal for each RF transponder of the first array and the second array;
determining, with at least one processor, a distance between the antenna and each of at least two RF transponders of the first array on the first portion of the body based on at least a first portion of the plurality of response signals;
determining, with at least one processor, a distance between the antenna and each of at least two RF transponders of the second array on the second portion of the body based on at least a second portion of the plurality of response signals;
determining, with at least one processor, a first difference between: the distance between the antenna and a first transponder of the at least two RF transponders of the first array and the distance between the antenna and a second transponder of the at least two RF transponders of the first array;
determining, with at least one processor, a second difference between: the distance between the antenna and a first transponder of the at least two RF transponders of the second array and the distance between the antenna and a second transponder of the at least two RF transponders of the second array; and
determining, with at least one processor, a relative location of the first portion of the body and the second portion of the body based at least partially on the first difference in distances, a distance between the at least two RF transponders of the first array, the second difference in distances, and a distance between the at least two RF transponders of the second array.

2. The method of claim 1 , wherein the first difference and the second difference are determined based on phases of the at least a portion of the plurality of response signals.

3. The method of claim 1 , wherein the plurality of arrays of RF transponders further comprise a third array of RF transponders arranged on a third portion of the body and a fourth array of RF transponders arranged on a fourth portion of the body, wherein the third portion of the body and the fourth portion of the body connect at a second joint of the body.

4. The method of claim 1 , wherein the plurality of arrays of RF transponders are integrated into a fabric material adapted to be worn on the body.

5. The method of claim 1 , wherein the reader device is arranged on the body and comprises the at least one processor.

6. The method of claim 1 , further comprising determining an angle of the first joint based on the relative location of the first portion of the body with respect to the second portion of the body.

7. The method of claim 1 , wherein the at least two RF transponders of the first array are spaced apart by a distance equal to or less than λ/4, where λ is a wavelength of the response signal for each of the at least two RF transponders of the first array.

8. The method of claim 7 , wherein each of the at least two RF transponders of the first array are arranged in-line with the first joint.

9. The method of claim 7 , wherein the at least two RF transponders of the second array are spaced apart by a distance equal to or less than λ/4, where λ is a wavelength of the response signal for the at least two RF transponders of the second array, and wherein each of the at least two RF transponders of the second array are arranged in-line with the first joint.

10. A system for tracking a body, comprising:
a plurality of arrays of radio frequency (RF) transponders arranged on a body, the plurality of arrays comprising a first array of RF transponders arranged on a first portion of the body and a second array of RF transponders arranged on a second portion of the body, the first portion of the body and the second portion of the body connecting at a first joint of the body such that the first array and the second array are separated by the first joint;
at least one processor programmed and/or configured to:
communicate, with an antenna, at least one activation signal to each RF transponder of the first array and the second array;
receive, with the antenna, a plurality of response signals from the first array and the second array, the plurality of response signals comprising at least one response signal for each RF transponder of the first array and the second array;
determine a distance between the antenna and each of at least two RF transponders of the first array on the first portion of the body based on at least a first portion of the plurality of response signals;
determine a distance between the antenna and each of at least two RF transponders of the second array on the second portion of the body based on at least a second portion of the plurality of response signals;
determine a first difference between: the distance between the antenna and a first transponder of the at least two RF transponders of the first array and the distance between the antenna and a second transponder of the at least two RF transponders of the first array;
determine a second difference between: the distance between the antenna and a first transponder of the at least two RF transponders of the second array and the distance between the antenna and a second transponder of the at least two RF transponders of the second array; and
determine a relative location of the first portion of the body and the second portion of the body based at least partially on the first difference in distances, a distance between the at least two RF transponders of the first array, the second difference in distances, and a distance between the at least two RF transponders of the second array.

11. The system of claim 10 , wherein the at least one processor comprises at least one first processor and at least one second processor, the system further comprising a reader device, the reader device including the at least one first processor and the antenna.

12. The system of claim 10 , wherein the first difference and the second difference are determined based on phases of response signals received from the at least two RF transponders of the first array.

13. The system of claim 10 , wherein the plurality of arrays of RF transponders further comprise a third array of RF transponders arranged on a third portion of the body and a fourth array of RF transponders arranged on a fourth portion of the body, wherein the third portion of the body and the fourth portion of the body connect at a second joint of the body.

14. The system of claim 10 , further comprising a fabric material adapted to be worn on the body, wherein the plurality of arrays of RF transponders are integrated into the fabric material.

15. The system of claim 10 , wherein the antenna is arranged on the body.

16. The system of claim 10 , wherein the at least one processor is further programmed or configured to determine an angle of the first joint based on the relative location

Assignees

• Univ Carnegie Mellon

Inventors

• Jin Haojian
• Yang Zhijian
• Kumar Swarun Kumar Suresh
• Hong Jason I

Classifications

• A61B5/1071 Primary

  measuring angles, e.g. using goniometers (A61B5/1123 takes precedence) · CPC title

• A61B5/1114 Primary

  Tracking parts of the body · CPC title

• A61B5/1126

  using a particular sensing technique · CPC title

• A61B5/6804

  Garments; Clothes · CPC title

• G01S13/72

  for two-dimensional [2D] tracking, e.g. combination of angle and range tracking, track-while-scan radar · CPC title