Optical Velocity Tracking for Paint Spray Gun

• US 20110216188A1
• Filed: 03/08/2010
• Published: 09/08/2011
• Est. Priority Date: 03/08/2010
• Status: Active Grant

• Current Assignee: Southwest Research Institute
• Original Assignee: Southwest Research Institute
• Inventors: Thwing, Clinton J., Laiche, Erika C., Bartlett, Jonathan D., Jones, David L.
• Granted Patent: US 9,245,163 B2
• Time in Patent Office: Days
• US Class Current: 348/135
• CPC Class Codes: B05B 12/004 comprising sensors for monitoring the delivery, e.g. by displaying the sensed value or generating an alarm B05B12/08 takes precedence; registering or indicating the condition or the working of machines or other apparatus in general G07C3/00
• CPC Class Codes: B05B 12/084 responsive to condition of liquid or other fluent material already sprayed on the target, e.g. coating thickness, weight or pattern
• CPC Class Codes: B05B 12/126 responsive to target velocity, e.g. to relative velocity between spray apparatus and target B05B9/06 takes precedence
• CPC Class Codes: B05B 7/02 Spray pistols; Apparatus for discharge for spraying particulate material B05B7/14; with means for heating the material to be sprayed B05B7/16; with means for supplying fluent material to a discharge device B05B7/24
• CPC Class Codes: G06F 18/00 Pattern recognition
• CPC Class Codes: H04N 7/18 Closed-circuit television [CCTV] systems, i.e. systems in which the video signal is not broadcast

Abstract

A method of tracking and reporting the velocity of a hand-held paint spray gun. The object to be painted is placed in a room having one or more fiducial walls. A camera is installed on the spray gun, with its field of view toward the one or more fiducial walls. As the object is painted, the camera detects fiducials, calculates their current position, and compares current positions to previous locations to determine movement and velocity. The current velocity is compared to a stored target velocity, and audible or visible feedback is provided to the spray gun operator.

Claims

1. A method of tracking velocity of a hand-held paint spray gun, comprising:

Placing an object to be painted in an area having at least one wall covered with a constellation of fiducials;

Storing the three-dimensional location and diameter of each fiducial in memory of a computer;

Placing a camera on the spray gun, the camera having a field of view of the at least one wall when the object is being painted;

Painting the object using the spray gun;

During painting, using the camera to acquire location and diameter data representing the location and diameter of one or more fiducials within the camera'"'"'s field of view;

using the location or diameter data to determine the current velocity of the spray gun;

comparing current velocity values to the stored target velocity value; and

Providing feedback, audio or visual, to the operator representing the relationship of the current velocity to the target velocity.

2. The method of claim 1, wherein the camera is an all optical camera, and the location and diameter data are derived from optical image data.

3. The method of claim 1, wherein the camera is an inertially assisted camera and the location and diameter data are derived in part from inertial measurement data.

4. The method of claim 1, wherein the field of view of the camera is in a direction perpendicular to the direction of spray of the spray gun.

5. The method of claim 1, wherein the step of providing feedback is performed by providing an audio signal whose frequency represents speed.

6. The method of claim 1, wherein the step of providing feedback is performed by activating one or more LEDs.

7. The method of claim 6, wherein the LEDs are located so as to illuminate the paint spray.

8. The method of claim 1, wherein the step of providing feedback is performed by a display of a gauge and needle.

9. A camera-processor velocity tracking device for mounting on a hand-held paint spray gun, for use in painting an object in an area having at least one wall covered with a constellation of fiducials, comprising:

A memory for storing the three-dimensional location and diameter of each fiducial;

A camera having a field of view of the at least one wall when the object is being painted;

A processor programmed to acquire location and diameter data representing the location and diameter of one or more fiducials within the camera'"'"'s field of view during painting of the object;

to use the location or diameter data to determine the current velocity of the spray gun;

to compare current velocity values to the stored target velocity value; and

An audio or visual feedback unit for providing feedback, audio or visual, to the operator representing the relationship of the current velocity to the target velocity.

10. The device of claim 9, wherein the camera is an all optical camera, and the location and diameter data are derived from optical image data.

11. The device of claim 9, wherein the camera is an inertially assisted camera and the location and diameter data are derived in part from inertial measurement data.

12. The device of claim 9, wherein the field of view of the camera is in a direction perpendicular to the direction of spray of the spray gun.

13. The device of claim 9, wherein the feedback unit provides an audio signal whose frequency represents speed.

14. The device of claim 9, wherein the feedback unit is one or more LEDs.

15. The device of claim 14, wherein the LEDs are mounted such that they illuminate the paint spray.

16. The device of claim 9, wherein the feedback unit is a display of a gauge and needle.