In-process vision detection of flaw and FOD characteristics

• US 7,688,434 B2
• Filed: 03/27/2008
• Issued: 03/30/2010
• Est. Priority Date: 11/24/2004
• Status: Active Grant

• Current Assignee: The Boeing Co.
• Original Assignee: The Boeing Co.
• Inventors: Hannebaum, Reed, Engelbart, Roger W., Pollock, Tim
• Primary Examiner(s): NGUYEN, SANG H
• Application Number:
  US12/056,326
• Publication Number:
  US 20090002693A1
• Time in Patent Office: 733 Days
• Field of Search: 3562371-2373, 156/358, 156/359, 156/378, 156/379, 156/380.9, 156/361, 156/272.8, 156/189, 156/351, 382/141, 382/149, 382/192, 700/110, 700/117
• US Class Current: 356/237.1
• CPC Class Codes: B29C 70/38 Automated lay-up, e.g. using robots, laying filaments according to predetermined patterns application heads for tyres B29D30/28
• CPC Class Codes: G01N 2021/8472 Investigation of composite materials
• CPC Class Codes: G01N 21/89 in moving material, e.g. running paper or textiles G01N21/90, G01N21/91, G01N21/94 take precedence

Abstract

An inspection system (9) includes an idler wheel (61) that is coupled to a fabrication system (8) and is in contact with a backing layer (65) of an applied material (64), A rotation sensor (63) monitors the idler wheel (61) and generates a rotational signal. A controller (24) is coupled to the rotation sensor (63) and determines a characteristic of one or more flaws and FOD (19) on a composite structure (12) in response to the rotation signal.

Claims

1. A method of determining flaw and FOD characteristics comprising:

rotating an idler wheel via a backing layer of a composite material;

monitoring said idler wheel and generating a rotational signal; and

determining at least one characteristic of at least one flaw and FOD on a portion of a composite structure in response to said rotation signal using a controller, wherein the controller stores the at least one characteristic of the at least one flaw and FOD for use in correcting the at least one flaw and FOD.

2. A method as in claim 1 further comprising:

acquiring images via at least one detector,

counting images to generate an image count; and

determining a linear distance along a composite structure in response to said image count.

3. The method as in claim 2 further comprising illuminating said composite structure.

4. The method as in claim 2 further comprising storing said images.

5. The method of claim 2 further comprising synchronizing said acquiring of images with said rotating of idler wheel.

6. The method of claim 2 further comprising blocking wavelengths of visible light from entering said at least one detector via at least one filter.

7. A method as in claim 1 further comprising:

counting revolutions of said idler wheel to generate a revolution count; and

determining a linear distance along a composite structure in response to said revolution count.

8. A method as in claim 1 wherein said at least one characteristic comprises at least one of size, location, position, type, density-per-unit area, and cumulative defect width-per-unit area.

9. A method as in claim 1 further comprising:

counting revolutions of said idler wheel to generate a revolution count;

counting cessations of said idler wheel to generate a cessation count; and

determining position of said at least one flaw and FOD in response to said revolution count and said cessation count.

10. A method as in claim 9 further comprising:

counting applied layers of said composite structure to generate an applied layer count; and

determining location of said at least one flaw and FOD in response to said revolution count, said cessation count, and said applied layer count.

11. A method as in claim 1 further comprising:

determining size of said at least one flaw and FOD; and

determining flaw area density in response to said portion and said size.

12. A method as in claim 1 further comprising:

counting said at least one flaw and FOD in a current frame and course to generate a current flaw and FOD frame count;

summing said current flaw and FOD frame count with flaws and FOD of two adjacent frames of a previous course to generate a resultant sum; and

determining flaw areal density for said portion in response to said resultant sum.

13. A method as in claim 1 further comprising:

determining size of said at least one flaw and FOD; and

determining cumulative gap width per unit area in response to said portion and said size.

14. A method as in claim 1 further comprising:

dividing said composite structure into a plurality of unit areas; and

determining said characteristic in response to said division.

15. A method as in claim 14 further comprising assigning angular cut frames of said plurality of unit areas a full frame unit area.

16. A method as in claim 1 further comprising altering operation of a fabrication system in response to said at least one characteristic.

17. A method as in claim 1 wherein determining at least one characteristic comprises determining cumulative gap width through summation of a plurality of gaps laterally across said portion perpendicular to a direction of material placement.

18. A method as in claim 17 wherein summing said plurality of gaps comprises assigning gap lengths to extend approximately an entire frame length.

19. A method as in claim 1 further comprising:

staggering frames; and

determining said at least one characteristic in response to said frame stagger.

20. The method of claim 1 further comprising using data stored by the controller to adjust operation of at least one of a fabrication system, an inspection system, and a lamination system to correct the at least one characteristic of the at least one flaw and FOD.