Force detecting sensor

1. A sensor for detecting input force, comprising:

a housing defining a cavity therein and a top surface; and

a contact element enclosed within said cavity, said contact element comprising an external surface;

said cavity comprising at least one wall having an inner surface, said at least one wall having a sensing device attached thereto and aligned against said inner surface of said at least one wall;

said contact element being configured to provide physical contact between said contact element and said sensing device on application of a mechanical interaction to said external surface; wherein

said external surface and said top surface provides a substantially flush profile extending from said external surface to said top surface; and

said sensing device comprises a pressure sensitive layer of variably resistive material sandwiched between a first conductive layer and a second conductive layer, said sensing device being configured to detect a magnitude of force and position of the mechanical interaction when applied.

2. A sensor according to claim 1 , wherein said sensing device is configured to detect magnitude and position in three dimensional Cartesian axes.

3. A sensor according to claim 1 , wherein said sensing device is a single point pressure sensor.

4. A sensor according to claim 3 , wherein said single point pressure sensor comprises a quantum tunneling composite material.

5. A sensor according to claim 1 , wherein said cavity comprises four side walls and a bottom wall, each said wall having one said sensing device attached thereto.

6. A sensor according to claim 1 , wherein said cavity comprises an elongate channel having two longitudinal side walls and a bottom wall, each said longitudinal side wall and said bottom wall comprising one said sensing device.

7. A sensor according to claim 1 , wherein said contact element and said cavity each comprise mutually co-operating profiles.

8. A sensor according to claim 1 , wherein said contact element comprises a v-shaped cross-sectional profile.

9. A sensor according to claim 1 , wherein said contact element comprises an elastomeric material.

10. A sensor according to claim 1 , wherein said external surface comprises a molded portion which comprises a finger-shaped profile.

11. A sensor according to claim 1 , wherein said sensor is configured to detect an external object.

12. A method of detecting an input force, comprising the steps of:

providing a sensor having a housing defining a cavity therein and a contact element enclosed by said cavity;

applying a mechanical interaction to an external surface of said contact element, said external surface and a top surface of said housing providing a substantially flush profile extending from said external surface to said top surface;

providing a physical contact between said contact element and a sensing device attached and aligned with an inner surface of a side wall of said cavity, wherein said sensing device comprises a pressure sensitive layer of variably resistive material sandwiched between a first conductive layer and a second conductive layer; and

detecting a force magnitude and position of force along three axes of said mechanical interaction in response to said physical contact.

13. A method of detecting an input force according to claim 12 , further comprising the step of: detecting an external object in contact with said sensor so as to provide a protective bumper.

14. A method of detecting an input force according to claim 12 , wherein said step of applying a mechanical interaction involves providing a sliding force along said external surface.

15. A method of detecting an input force according to claim 12 , wherein said step of applying a mechanical interaction involves providing a toggle function along said external surface.

16. A method of manufacturing a sensor for detecting input force, comprising the steps of:

producing a housing having a top surface;

providing said housing with a cavity comprising at least one wall;

aligning a sensing device against an inner surface of said at least one wall, said sensing device being configured to detect a magnitude of force and position of a mechanical interaction when the mechanical interaction is applied;

attaching said sensing device to said inner surface of said at least one wall; and

positioning a contact element into said cavity such that said contact element is enclosed by said cavity and such that an external surface of said contact element and said top surface provides a substantially flush profile extending from said external surface to said top surface;

said contact element being able to provide physical contact between said contact element and said sensing device on application of a mechanical interaction to said external surface; and

said sensing device comprises a pressure sensitive layer of variably resistive material sandwiched between a first conductive layer and a second conductive layer.

17. A method of manufacturing according to claim 16 , wherein in said step of positioning said contact element into the cavity, said contact element is positioned so as to mutually co-operate with said cavity.

18. A method of manufacturing according to claim 17 , wherein said contact element is produced to have a v-shaped cross-sectional profile.