Hand-held tire scanner

1. A hand-held device for obtaining a three-dimensional topological surface profile of a tire, the hand-held device comprising:

a light source arranged in use to generate a pattern of light, and to project said pattern of light onto a surface of the tire;

a detector arranged to image the surface of the tire;

a plurality of guides linked by a linking assembly and arranged to generate a signal corresponding to movement of the hand-held device along the surface of the tire; and

at least one processor configured to generate the three-dimensional topological surface profile of the tire using data obtained from an image of the surface of the tire and the signal generated by the guides.

2. The hand-held device as claimed in claim 1 , wherein guides of the plurality of guides are arranged in a concave arc extending in a direction of said movement of the hand-held device.

3. The hand-held device as claimed in claim 1 , wherein the at least one processor is further configured to identify tire side walls by analyzing a directionality of the signal generated by the plurality of guides to determine a position of an outer edge and an inner edge of the tire.

4. The hand-held device as claimed in claim 1 wherein the plurality of guides comprises a rotary encoder for generating the signal.

5. The hand-held device as claimed in claim 4 , wherein the rotary encoder is disposed in a sealed housing in the hand-held device.

6. The hand-held device as claimed in claim 1 , wherein the projected pattern of light is oriented in a direction transverse to a direction of said movement of the hand-held device.

7. The hand-held device as claimed in claim 1 , further comprising a visual, audible and/or haptic indicator configured to provide visual, audible and/or haptic feedback to indicate that a scan is complete, a scan is incomplete, or that insufficient or poor data has been obtained from a scanned area.

8. The hand-held device as claimed in claim 1 wherein the light source is arranged to project said pattern of light through an aperture in a base of the hand-held device.

9. The hand-held device as claimed in claim 8 , wherein the base is connected to a housing of the hand-held device such that the base can be rotated away from the hand-held device to expose the aperture.

10. The hand-held device as claimed in claim 1 , wherein guides of the plurality of guides comprise guide wheels.

11. The hand-held device as claimed in claim 10 , wherein the guide wheels are provided on axles linked by the linking assembly.

12. The hand-held device as claimed in claim 1 , wherein the linking assembly comprises one or more gears.

13. The hand-held device as claimed in claim 1 , further comprising a wireless transceiver for connecting to an external device, wherein the wireless transceiver is configured to communicate to the external device to provide measurement data to the external device.

14. The hand-held device according to claim 1 wherein the hand-held device is configured to slide along a guide rail.

15. A method of obtaining data for generating a three-dimensional topological surface profile of a tire, using a hand-held device, the method comprising:

generating a pattern of light projecting said pattern of light onto a surface of the tire;

imaging a region of the surface of the tire;

moving the hand-held device over the surface of the tire on a plurality of guides, wherein guides of the plurality of guides are linked by a linking assembly;

generating, by the guides, a signal corresponding to movement of the hand-held device along the surface of the tire; and

generating the three-dimensional topological surface profile of the tire using data obtained from an image of the surface of the tire and the signal generated by the guides.

16. The method as claimed in claim 15 , further comprising identifying tire side walls by analyzing a directionality of the signal generated by the plurality of guides to determine a position of an outer edge and an inner edge of the tire.

17. The method as claimed in claim 15 , comprising projecting the pattern of light so that the pattern of light is oriented in a direction transverse to a direction of said movement of the hand-held device.

18. The method as claimed in claim 15 , wherein the hand-held device comprises a battery, the method further comprising the hand-held device entering a low power or sleep mode when no signal corresponding to said movement of the hand-held device is generated.

19. The method as claimed in claim 15 , further comprising communicating with an external device to provide measurement data to the external device;

communicating data obtained from an image of the rolling surface of the tire and the signal generated by the plurality of guides to the external device; and

using the external device to determine one or more of: a three-dimensional topological surface profile of the tire; wheel alignment information; tire inflation information; and stopping distance information.

20. The method as claimed in claim 15 , comprising using the hand-held device to determine one or more of: a three-dimensional topological surface profile of the tire; wheel alignment information; tire inflation information; and stopping distance information.

21. The method as claimed in claim 15 , further comprising:

imaging a vehicle registration plate to generate an image;

identifying the vehicle registration plate based on the image;

retrieving vehicle information and/or tire information based on the identified vehicle registration plate; and

using said retrieved vehicle information and/or tire information to determine one or more of: a three-dimensional topological surface profile of the tire; wheel alignment information; tire inflation information; and stopping distance information.

22. The method as claimed in claim 15 , further comprising:

placing a guide rail in a fixed relationship relative to the surface of the tire; and

moving the hand-held device along the guide rail as the hand-held device moves over the surface of the tire.