TRACKING DEVICE TILT CALIBRATION USING A VISION SYSTEM

1 . A method comprising the steps of:

connecting a vision system to a computer, the vision system adapted to monitor a visual space;

detecting, by the vision system, a tracking object in the visual space, the tracking object having an at-rest tilt angle;

executing, by the computer, a graphics application program;

outputting, by the vision system to the computer, spatial coordinate data representative of the location of the tracking object within the visual space;

mapping a horizontal portion and a vertical portion of the spatial coordinate data to a display connected to the computer; and

calibrating the tracking object to establish the at-rest tilt angle as a default value in the graphics application program.

2 . The method according to claim 1 , wherein the tracking object further comprises an at-rest bearing angle, and the calibrating step further includes establishing the at-rest bearing angle as a default value in the graphics application program.

3 . The method according to claim 1 , wherein the calibrating step includes horizontal, vertical, and depth coordinates in the visual space.

4 . The method according to claim 1 , wherein the graphics application program includes a configurable range of drawing implement tilt angle values, and the calibrating step maps a portion of the tracking object tilt angle range to the full range of drawing implement tilt angle values.

5 . The method according to claim 4 , wherein the portion of the tracking object tilt angle range is 0° to 60°.

6 . The method according to claim 1 , wherein the calibrating step maps the at-rest position of the tracking object in a plurality of locations within the visual space, and the computer interpolates an estimated at-rest position for locations between the calibrated positions.

7 . The method according to claim 1 , wherein the calibrating step obtains position information when a user performs practice strokes in the visual space.

8 . The method according to claim 1 , wherein the calibrating step comprises a procedure that records the at-rest position of the tracking object over time, and recalibrates the original at-rest position.

9 . The method according to claim 1 , further comprising the steps of transferring the calibrated tracking object settings from a first graphic computer software system to a second graphic computer software system, computing a difference between the respective visual spaces, and scaling the settings to the second visual space.

10 . The method according to claim 1 , further comprising the step of ignoring angular changes to the tilt angle below a pre-defined threshold.

11 . The method according to claim 10 , wherein the threshold is 3°.

12 . A digital graphics computer system, comprising:

a computer, comprising:

one or more processors;

one or more computer-readable memories; and

one or more computer-readable tangible storage devices; and

program instructions stored on at least one of the one or more storage devices for execution by at least one of the one or more processors via at least one of the one or more memories;

a display connected to the computer;

a tracking object having an at-rest tilt angle; and

a vision system connected to the computer, the vision system comprising one or more image sensors adapted to capture the location of the tracking object within a visual space, the vision system adapted to output to the computer spatial coordinate data representative of the location of the tracking object within the visual space;

the computer program instructions comprising:

program instructions to execute a graphics application program and output to the display;

program instructions to map at least a horizontal and vertical portion of the spatial coordinate data of the tracking object as input to a graphics engine of the graphics application program; and

program instructions to calibrate the tracking object to establish the at-rest tilt angle as a default value in the graphics application program.

13 . The digital graphics computer system of claim 12 , further comprising program instructions to calibrate the tracking object to establish an at-rest bearing angle as a default value in the graphics application program.

14 . The digital graphics computer system of claim 12 , wherein the graphics application program includes a configurable range of drawing implement tilt angle values, and further comprising program instructions to map a portion of the tracking object tilt angle range to the full range of drawing implement tilt angle values.

15 . The digital graphics computer system of claim 12 , further comprising program instructions to calibrate the at-rest position of the tracking object in a plurality of locations within the visual space, and interpolate an estimated at-rest position for locations between the calibrated positions.

16 . The digital graphics computer system of claim 15 , further comprising program instructions to request the user perform one or more reaches to the extents of the visual space, and calibrate the at-rest position of the tracking object at each extent.

17 . The digital graphics computer system of claim 15 , further comprising program instructions to calibrate the at-rest position of the tracking object when the user is sitting and standing.

18 . The digital graphics computer system of claim 12 , further comprising program instructions to record the at-rest position of the tracking object over time, and recalibrate the original at-rest position.

19 . The digital graphics computer system of claim 12 , further comprising program instructions to transfer the calibrated tracking object settings from a first graphic computer software system to a second graphic computer software system, compute a spatial difference between the respective visual spaces, and scale the calibrated settings to the second visual space.

20 . The digital graphics computer system of claim 12 , further comprising program instructions to ignore changes to the tilt angle of the tracking object below a pre-defined threshold.