Electronic device comprising magnetometers

1. An electronic interactive device comprising:

an interaction surface for use with a user borne device, wherein the interaction surface comprises a contact detection surface configured to detect a contact event of a user borne device with the interaction surface;

a plurality of magnetometers defining a reference coordinate system of the interaction surface, wherein each magnetometer of the plurality of magnetometers has a rigid spatial relationship to the other magnetometers, and the plurality of magnetometers defines a sensing volume proximate to the interaction surface;

processing circuitry communicably coupled to at least the contact detection surface and the plurality of magnetometers; and

a magnet coupled to the user borne device proximate to the interaction surface, wherein at least one position and/orientation of the magnet relative to a longitudinal axis of the user borne device corresponds to at least one mode of the user borne device,

wherein the plurality of magnetometers is configured to perform magnetic field measurements of the magnet, and to provide magnetic field measurement data characterizing the magnetic field measurements to the processing circuitry;

wherein the processing circuitry is configured to determine the at least one position and/or orientation of the magnet relative to a longitudinal axis of the user borne device; and

wherein the processing circuitry is configured to determine a distance separating the magnet from the interaction surface and/or an orientation of the magnet relative to a longitudinal axis of the user borne device from the interaction surface when the contact event occurs.

2. The electronic interactive device according to claim 1 ,

wherein the processing circuitry is configured to determine the distance separating the magnet from the interaction surface when the contact event occurs by:

detecting a position of the magnet on the longitudinal axis of the user borne device, relative to the interaction surface;

computing an intersection of a virtual projection of a magnetic moment vector of the magnet with the interaction surface;

defining a proximal reference point of the longitudinal axis of the user borne device when the contact event occurs; and

computing the distance between the proximal reference point and the position of the magnet on the longitudinal axis of the user borne device.

3. The electronic interactive device according to claim 1 ,

wherein the processing circuitry further comprises non-volatile memory comprising a library of position and/or orientation characteristics of the magnet relative to a plurality of magnet placement distances in the user borne device defining a plurality of modes of the user borne device; and

wherein the processing circuitry is further configured to identify, using the respective position and/or orientation characteristics of the magnet stored in the library, and the contact event detected by the contact detection surface, that the user borne device is in a specified mode based on the position and/or orientation of the magnet of the user borne device.

4. The electronic interactive device according to claim 1 , further comprising:

a communication device,

wherein the processing circuitry is configured to communicate the at least one mode, the position and/or orientation characteristic of the magnet of the user borne device, and/or the coordinates of a contact point of a user borne device on the interaction surface to a host device.

5. The electronic interactive device according to claim 1 ,

wherein the contact detection surface comprises a capacitive sensing arrangement.

6. The electronic interactive device according to claim 1 ,

wherein the contact detection surface comprises a force sense resistor sensing arrangement, and the contact detection surface is configured to output a contact pressure measurement characterising the pressure exerted on the interaction surface during the contact event.

7. The electronic interactive device according to claim 1 ,

wherein the processing circuitry is configured to detect that the magnet is located at one of a plurality of distances from a proximal nib of the user borne device, and to define the at least one mode based on the determined distance.

8. The electronic interactive device according to claim 6 ,

wherein the processing circuitry is configured to detect that the magnet has been rotated by a predefined angle relative to a non-axial rotation vector, wherein the non-axial rotation vector and the longitudinal axis are characterised by a non-zero included angle, and the at least one mode is set based on the detected predefined non-axial rotation angle.

9. The electronic interactive device according to claim 1 , further comprising:

a display;

wherein the processing circuitry is configured to adjust a drawing mode of a software drawing program executed by the processing circuitry based on the at least one position and/or orientation of the magnet of the user borne device.

10. The electronic interactive device according to claim 9 ,

wherein the processing circuitry is further configured to change a drawing mode of the software drawing program from a first type of drawing mode to a second type of drawing mode in response to detecting a predetermined distance separating the magnet from the interaction surface and/or an orientation of the magnet relative to a longitudinal axis of the user borne device from the interaction surface when the contact event occurs and/or

where the drawing mode comprises a thickness, colour, opacity, or line texture.

11. The electronic interactive device according to claim 1 , wherein the interactive device comprises a rigid back panel and a frame, the plurality of magnetometers being fixedly arranged in an enclosure of the electronic interactive device that is joined to the frame.

12. A computer implemented method comprising:

performing magnetic field measurements of a magnet coupled to a user borne device proximate to an interaction surface of an electronic interactive device;

detecting a contact event of a user borne device with the interaction surface, using a contact detection surface comprised in the interaction surface;

determining at least one position and/or orientation of the magnet relative to a longitudinal axis of the user borne device;

determining a distance separating the magnet from the interaction surface when the contact event occurs; and

determining, by the electronic interaction device, a mode of the user borne device based on the at least one position and/or orientation of the magnet relative to the longitudinal axis of the user borne device.

13. The computer implemented method according to claim 12 , further comprising:

determining the distance separating the magnet from the interaction surface when the contact event occurs by:

detecting a position of the magnet on the longitudinal axis of the user borne device, relative to the interaction surface;

computing an intersection of a virtual projection of a magnetic moment vector of the magnet with the interaction surface;

defining a proximal reference point of the longitudinal axis of the user borne device when the contact event occurs; and

computing the distance between the proximal reference point and the position of the magnet on the longitudinal axis of the user borne device.

14. A system comprising:

an electronic interactive device according to claim 1 ; and

a user borne device comprising a magnet configured to be linearly translatable along, or rotatably around, a longitudinal axis of the user borne device.

15. The system according to claim 14 , further comprising:

a host device configured to receive the distance separating the magnet from the interaction surface and/or an orientation determined by the processing circuitry of the electronic interactive device,

a communications network configured to communicably couple the electronic interactive device with the host device.

16. The system according to claim 14 , wherein the magnet is linearly translatable between different fixed locations inside the user borne device via a slider mechanism.

17. A non-transitory computer-readable medium storing computer-executable instructions which, when performed by processing circuitry of a system, cause the system to perform operations comprising:

performing magnetic field measurements of a magnet coupled to a user borne device proximate to an interaction surface of an electronic interactive device;

detecting a contact event of a user borne device with the interaction surface, using a contact detection surface comprised in the interaction surface;

determining at least one position and/or orientation of the magnet relative to a longitudinal axis of the user borne device;

determining a distance separating the magnet from the interaction surface when the contact event occurs; and

determining, by the electronic interaction device, a mode of the user borne device based on the at least one position and/or orientation of the magnet relative to the longitudinal axis of the user borne device.

18. The electronic interactive device of claim 1 , wherein a mode of the user borne device corresponds to a type of virtual writing instrument or a characteristic of the virtual writing instrument.

19. The electronic interactive device of claim 1 , wherein a one mode of the user borne device corresponds to a type of virtual writing instrument or a characteristic of the virtual writing instrument,

wherein the type of virtual writing instrument is chosen from a writing instrument, a drawing instrument, or an erasing instrument, and

wherein the characteristic of the virtual writing instrument is chosen from thickness, color, opacity, or line texture.

20. The computer implemented method of claim 12 , wherein the mode of the user borne device identifies a type of virtual writing instrument or adjusts a characteristic of the virtual writing instrument.