Image processing for laser peening

• US 6,292,584 B1
• Filed: 04/08/1998
• Issued: 09/18/2001
• Est. Priority Date: 04/08/1998
• Status: Expired due to Fees

• Current Assignee: LSP Technologies Incorporated
• Original Assignee: LSP Technologies Incorporated
• Inventors: Clauer, Allan H., Dulaney, Jeffrey L., OʼLoughlin, Mark E.
• Primary Examiner(s): Couso, Jose L.
• Assistant Examiner(s): Dang, Duy M.
• Application Number:
  US09/057,107
• Time in Patent Office: 1,259 Days
• Field of Search: 382/141, 382/145, 382/148, 382/149, 382/151, 382/152, 382/153, 219/121.84, 219/121.6, 219/121.68, 219/121.85, 219/121.73, 364/474.08, 364/552
• US Class Current: 382/151
• CPC Class Codes: B23K 26/032 using optical means
• CPC Class Codes: B23K 26/0643 comprising mirrors
• CPC Class Codes: B23K 26/0648 comprising lenses
• CPC Class Codes: B23K 26/356 by shock processing
• CPC Class Codes: C21D 10/005 by laser shock processing

Abstract

An image processing system for monitoring a laser peening process includes a laser peening system having a workpiece positioner and a system controller. A video camera is utilized for forming an electronic image of at least a portion of a workpiece. An image processing computer is connected to the video camera, and the laser peening controller includes a program to determine a position of the workpiece.

Claims

1. An image processing system for use with a laser peening system having a workpiece positioner and controller which communicate together passing information encoding a position of a workpiece, said image processing system comprising:

a video camera for forming an electronic image of the workpiece; and

a programmed image processing computer connected to said video camera and laser peening system controller, said computer programmed to determine a calculated position of the workpiece based upon said electronic image, said computer determining the difference between said calculated position and the encoded position and sending a signal to the laser peening controller system if said difference is greater than a predetermined range.

2. The image processing system of claim 1 in which the laser peening system creates a laser spot with a particular size on the workpiece, said computer programmed to calculate the size of said laser spot by operations on said electronic image, said computer sending a signal to said laser peening system if said calculated spot size is outside of a predetermined range.

3. The image processing system of claim 1 in which the laser peening system applies an opaque overlay on the workpiece, said computer determining from said electronic image whether the laser peening system actually applied the opaque overlay and sending a signal to the laser peening system in the event said computer determined that no opaque overlay was applied.

4. An image processing system for use with a laser peening system for creating a laser spot of a particular size on a workpiece, said image processing system comprising:

a video camera for forming an electronic image of at least a portion of the workpiece; and

a programmed image processing computer connected to said video camera, and laser peening system, said computer programmed to calculate the size of said laser spot by operations on said electronic image, said computer sending a signal to said laser peening system if said calculated spot size is outside of a predetermined range.

5. The imaging processing system of claim 4 in which at least two video cameras are utilized such that the workpiece is placed between said at least two video cameras.

6. An image processing system for use with a laser peening system having an opaque overlay applicator to apply opaque overlay to a workpiece, said image processing system comprising:

a video camera for forming an electronic image of the workpiece; and

a programmed image processing computer connected to said video camera and laser peening system, said computer determining from said electronic image whether the laser peening system actually applied the opaque overlay and sending a signal to the laser peening system in the event said computer determines that no opaque overlay was applied.

7. A method of controlling a laser peening system utilizing dual-sided processing, said method comprising the steps of:

applying a laser beam to opposite sides of a workpiece;

determining the size of the spots on each side of the workpiece created from the laser beams with a video camera; and

adjusting at least one of the spot sizes to then create the same sized spot on each side of the workpiece on a subsequent laser beam impact.

8. The method of claim 7 in which the determining step utilizes a video camera on opposite sides of the workpiece.

9. A method of controlling a laser peening system having a workpiece positioner and a system controller, said method comprises the steps of:

applying an opaque overlay to the workpiece over a first area to be laser peened;

applying a laser beam to a spot on said opaque overlay at said first area;

repositioning the workpiece; and

determining the integrity of said opaque overlay at a second area to be laser peened using an image processing system, said second area adjacent to said first area.

10. The method of claim 9 in which said integrity information is transferred to said system controller.

11. The method of claim 9 in which said integrity information is used to reposition said workpiece to a third area if the condition of the opaque overlay at said second area spot is out of predetermined tolerances.

12. The method of claim 9 in which said repositioning step is omitted, so that the laser beam would strike said second area if the opaque overlay is still intact.

13. The method of claim 9 in which said opaque overlay is tape.

14. The method of claim 9 in which said opaque overlay is paint.

15. The method of claim 9 in which said opaque overlay is a coating.

16. A method of controlling a laser peening system utilizing dual-sided processing, said method comprising the steps of:

applying a laser beam to opposite sides of a workpiece;

determining the size of the laser spots on each side of said workpiece via an image processing system; and

adjusting at least one of the laser spot sizes to then create an equal sized laser spot on each side of the workpiece.

17. The method of claim 16 in which said method is used as an alignment method prior to laser peening a workpiece.

18. The method of claim 16 in which said adjustment step is made by repositioning the workpiece.

19. The method of claim 16 in which said adjustment step is made by repositioning one of a lens and mirror.

20. A method of controlling laser peening system utilizing dual-sided processing, said method comprising the steps of:

applying a laser beam to opposite sides of a workpiece;

determining the position of the laser spots on each side of said workpiece via an image processing system; and

adjusting at least one of the laser spot positions to provide laser spots on opposite sides of the workpiece which are concentric with each other along a line through the workpiece.

21. The method of claim 20 in which said method is used as an alignment method prior to laser peening a workpiece.

22. The method of claim 20 in which said adjustment step is made by repositioning the workpiece.

23. The method of claim 20 in which said adjustment step is made by repositioning one of a lens and mirror.

24. A method of controlling a laser peening system utilizing dual-sided processing, said method comprising the steps of:

applying a laser beam to opposite side of a workpiece;

determining the position and size of the laser spots on each side of said workpiece via an image processing system; and

adjusting at least one of the laser beams such that the shock waves generated on opposite sides of the workpiece substantially overlap each other as they pass through the workpiece.

25. The method of claim 24 in which said method is used as an alignment method prior to laser peening a workpiece.

26. The method of claim 24 in which said adjustment step is made by repositioning the workpiece.

27. The method of claim 24 in which said adjustment step is made by repositioning one of a lens and mirror.