SPATIAL TRACKING SYSTEM AND METHOD

• US 20120001644A1
• Filed: 06/30/2010
• Published: 01/05/2012
• Est. Priority Date: 06/30/2010
• Status: Active Grant

• Current Assignee: Philips IP Ventures B.V. (Koninklijke Philips N.V.)
• Original Assignee: Access Business Group International LLC (Alticor Incorporated)
• Inventors: Baarman, David W., Schwannecke, Joshua K., Stoner, William T. Jr., Gauche, Scott A., Nussbaum, Ryan Joseph, VanderStel, Nicholas J., VanOss, Jeffrey Lee
• Granted Patent: US 8,866,495 B2
• Time in Patent Office: Days
• US Class Current: 324/629
• CPC Class Codes: G01D 5/2066 by movement of a single coil with respect to a single other coil
• CPC Class Codes: G01D 5/2073 by movement of a single coil with respect to two or more coils
• CPC Class Codes: G01D 5/2086 by movement of two or more coils with respect to two or more other coils

Abstract

The specification discloses a simple and effective system for tracking position and rotation of an object or portable device located within an electromagnetic field. The electromagnetic field may be produced by a primary coil, which inductively couples with one or more secondary coils located within a portable device. The relative strength of this inductive coupling may be used to determine the position, rotation, or both of the portable device relative to the primary coil.

Claims

1. A portable device for tracking spatial information, comprising:

at least one secondary placed within an external electromagnetic field that receives power from said external electromagnetic field to supply energy to device circuitry; and

a controller that senses a strength characteristic of said external electromagnetic field received by said at least one secondary to determine spatial information about said portable device.

2. The portable device of claim 1, wherein said spatial information includes at least one of rotation and a characteristic of position.

3. The portable device of claim 2, wherein said strength changes based on an angle of said secondary relative to said external magnetic field.

4. The portable device of claim 2, wherein said strength changes based on a characteristic of position of said secondary relative to said external magnetic field.

5. The portable device of claim 1, further comprising at least one sensor for providing additional spatial information about said portable device, wherein said controller uses said additional spatial information to determine said spatial information.

6. The portable device of claim 5, wherein said spatial information is correlated with said additional spatial information to improve said additional spatial information from said at least one sensor.

7. The portable device of claim 1, wherein said at least one secondary includes three secondaries orthogonally situated with respect to each other.

8. The portable device of claim 1, wherein each of the at least one secondary includes two secondary coils separated by a shield.

9. A system for tracking spatial information about a portable device, comprising:

a primary producing an electromagnetic field to said portable device;

said portable device including at least one secondary having an inductive coupling with said primary, wherein said portable device determines spatial information based on a strength characteristic of said inductive coupling between each of the at least one secondary and said primary.

10. The system of claim 9, further comprising an additional sensor capable of providing sensor information about said portable device, wherein said portable device uses said sensor information to determine said spatial information.

11. The system of claim 10, wherein said sensor information and said spatial information are compared to compensate for drift in said sensor information.

12. The system of claim 9, wherein said spatial information includes at least one of pitch, roll, yaw, and a characteristic of position relative to said primary.

13. The system of claim 9, wherein each of said at least one secondary includes two secondary coils separated by a shield.