Magnetic sensing user interface device methods and apparatus using electromagnets and associated magnetic sensors

• US 9,678,577 B1
• Filed: 08/20/2012
• Issued: 06/13/2017
• Est. Priority Date: 08/20/2011
• Status: Expired due to Fees

• Current Assignee: Seescan, Inc.
• Original Assignee: Seescan, Inc.
• Inventors: Rutledge, Austin S., Merewether, Ray, Martin, Michael J., Olsson, Mark S.
• Primary Examiner(s): Boddie, William
• Assistant Examiner(s): Shapiro, Leonid
• Application Number:
  US13/590,099
• Time in Patent Office: 1,758 Days
• Field of Search: 345156, 345157, 345160, 345161, 345163, 345167, 345179
• CPC Class Codes: G06F 3/02 Input arrangements using manually operated switches, e.g. using keyboards or dials
• CPC Class Codes: G06F 3/0338 with detection of limited linear or angular displacement of an operating part of the device from a neutral position, e.g. isotonic or isometric joysticks
• CPC Class Codes: H03K 17/9505 Constructional details
• CPC Class Codes: H03K 17/97 using a magnetic movable element

Abstract

User interface devices with electromagnetic dipole array and associated magnetic sensors, control circuits, and processing elements for determining user actuation of the device are disclosed. In one embodiment a user interface device include an electromagnetic dipole array coupled to an actuator, along with a three-axis magnetic sensor and control and processing elements for controlling driving currents to the dipole array and sensing and processing received magnetic field signals to determine movement or displacement of the actuator.

Claims

1. A magnetic sensing user interface device, comprising:

an actuator element including an electromagnetic dipole array having a plurality of dipole elements for generating magnetic fields in a plurality of orthogonal dimensions;

a control circuit for separately selectively energizing ones of the plurality of dipole elements of the dipole array to generate the magnetic fields; and

a three-axis magnetic sensor element associated with the dipole array and configured to sense the magnetic fields in three orthogonal axes at a compact point in space based on a position of the actuator element and provide magnetic sensor output data signals corresponding to the sensed magnetic fields;

a printed circuit substrate on which the magnetic sensor is disposed;

a plurality of springs mechanically coupled between the actuator and substrate to float the electromagnetic dipole array relative to the magnetic sensor; and

electronics, including a processing element, to determine, based at least in part on the three-axis magnetic sensor output data signals, a position or movement of the actuator element.

2. The device of claim 1, wherein the electromagnetic dipole array comprises a cross-shaped array having a pair of dipole elements on orthogonal prongs of the array.

3. The device of claim 2, wherein the dipole array comprises a ferrite cross-shaped substrate with windings on each of the orthogonal prongs.

4. The device of claim 1, wherein the electromagnetic dipole array comprises a three-dimensional array having three dipole elements on three orthogonal prongs of the array.

5. The device of claim 4, wherein the dipole array comprises a ferrite cross-shaped substrate with windings on each of the orthogonal prongs.

6. The device of claim 1, wherein the dipole array comprises three chip-scale inductors disposed in a pyramid configuration on a substrate.

7. The device of claim 1, wherein the control circuit comprises an electronic circuit for selectively providing currents to ones of a plurality of elements of the dipole array to generate the magnetic fields.

8. The device of claim 7, wherein the currents are sequentially applied to ones of the plurality of elements of the dipole array.

9. The device of claim 7, wherein the current are sequentially applied to offset a sensed ambient magnetic field condition.

10. The device of claim 1, wherein the magnetic sensor elements is a three dimensional magnetic field sensor.

11. The device of claim 1, wherein the magnetic sensor element is a compass sensor.

12. The device of claim 1, wherein the position of the actuator is a rest or neutral position.

13. The device of claim 1, wherein the position of the actuator is an actuated position offset from a rest or neutral position.

14. The device of claim 1, further comprising:

a memory; and

a processing element coupled to the memory, the processing element configured to;

receive the magnetic sensor output data;

generate an estimated position or deformation of the actuator based at least in part on the received output data; and

generate, based on the estimated position or deformation of the actuator element, an output signal usable by an electronic computing system coupled to the user interface device.

15. The device of claim 1, further comprising:

a substrate on which the magnetic sensor is disposed; and

three or more springs disposed around the outside of the dipole array mechanically coupled between the actuator and substrate to float the electromagnetic dipole array relative to the magnetic sensor;

wherein the magnetic sensor is a multi-axis magnetic sensor for sensing magnetic fields in three orthogonal axes at a compact point in space.

21. The device of claim 1, wherein the magnetic sensor element is a three-axis magnetic sensor element for sensing magnetic fields in three orthogonal axes at a compact point in space.

22. The device of claim 14, wherein the output signal corresponds to an estimated deformation of the actuator.

16. A user interface device, comprising:

an actuator element including an electromagnetic dipole array having a plurality of dipole elements for generating magnetic fields;

a control circuit for selectively energizing ones of a plurality of dipole elements of the dipole array to generate the magnetic fields;

a magnetic sensor element associated with the dipole array and configured to sense the magnetic fields at a position of the actuator element and provide magnetic sensor output data corresponding to the sensed magnetic fields;

a substrate on which the magnetic sensor is disposed; and

a plurality of springs mechanically coupled between the actuator and substrate to float the electromagnetic dipole array relative to the magnetic sensor;

wherein the springs are conductors for carrying driving current from the control circuit to the electromagnetic dipole array.

17. A method for electromagnetic sensing in a user interface device, comprising:

selectively driving a first current in a first dipole element of a dipole array coupled to an actuator floatably coupled to move in six degrees of freedom relative to a base;

sensing, at a multi-axis magnetic sensor, magnetic fields generated by the first dipole element;

providing magnetic sensor output data corresponding to the first sensed magnetic fields;

selectively driving a second current in a second dipole element, orthogonally oriented relative to the first dipole element, of the dipole array;

sensing, at the multi-axis magnetic sensor, magnetic fields generated by the second dipole element;

providing magnetic sensor output data corresponding to the second sensed magnetic fields;

receiving the magnetic sensor output data at a processing element; and

determining, based at least in part on the magnetic sensor output data, a location or position of the actuator.

18. The method of claim 17, wherein the first dipole element and the second dipole element are disposed on orthogonal prongs of the dipole array in a cross-configuration.

19. The method of claim 17, wherein the first and/or second driving currents are adjusted to compensate for a sensed ambient magnetic field condition.

20. The method of claim 17, wherein the magnetic sensor is a three-axis magnetic sensor and the magnetic sensor output data corresponds to three-dimensional magnetic field data.