Method and apparatus for inspecting countersinks using composite images from different light sources

• US 9,299,118 B1
• Filed: 04/18/2012
• Issued: 03/29/2016
• Est. Priority Date: 04/18/2012
• Status: Active Grant

• Current Assignee: The Boeing Co.
• Original Assignee: The Boeing Co.
• Inventors: McGraw, Michael D.
• Primary Examiner(s): Patel, Jay
• Assistant Examiner(s): SUH, JOSEPH JINWOO
• Application Number:
  US13/449,590
• Time in Patent Office: 1,441 Days
• Field of Search: 348/94
• US Class Current: 1/1
• CPC Class Codes: B07C 5/10 measured by light-responsive means sorting according to colour B07C5/342
• CPC Class Codes: G01B 11/002 for measuring two or more coordinates
• CPC Class Codes: G01B 11/02 for measuring length, width or thickness G01B11/08 takes precedence
• CPC Class Codes: G01B 11/12 internal diameters
• CPC Class Codes: G01B 11/2509 Color coding
• CPC Class Codes: G01B 11/2513 with several lines being projected in more than one direction, e.g. grids, patterns
• CPC Class Codes: G01B 11/272 using photoelectric detection means
• CPC Class Codes: G06T 1/0014 Image feed-back for automatic industrial control, e.g. robot with camera robots B25J19/023

Abstract

Method and apparatus for measuring dimensionality of a component are disclosed herein. At least a first image may be collected from a first camera of an aperture or a first precision countersink of the component. The first camera may be in a first position and may operate in one or more luminance environments. At least a second image may be collected from a second camera of the aperture or a second precision countersink of the component. The second camera may be in a second position and may operate in an alternative lighting environment to differentiate characteristic features including hole and countersink against their intersection with the component. Positional and process refinement parameters may be calculated for, and provided to, one or more numerically controlled mechanisms, based on the collected first and second images.

Claims

1. A method for measuring dimensionality of a component, the method comprising:

collecting at least a first plurality of images from a first camera of a first precision countersink of the component, wherein each of said first plurality of images is collected using a different light source of a plurality of light sources, and wherein a first image of said first plurality of images is captured by said first camera when a first light source of said plurality of light sources is activated and a second light source of said plurality of light sources is inactivated, and a second image of said first plurality of images is captured by said first camera when said second light source of said plurality of light sources is activated and said first light source of said plurality of light sources is inactivated, wherein said first camera comprises a first lens and is attached to and housed within a housing, and wherein said first lens is circumferentially shielded by a first end portion of a first elongate hollow tube that extends from said housing, said first elongate hollow tube further comprising a second end portion that comprises a first mirror and a first opening;

generating a composite image of said first precision countersink using said first plurality of images, wherein generating said composite image of said first precision countersink comprises superimposing said first plurality of images;

calculating positional and process refinement parameters for one or more numerically controlled mechanisms associated with said first precision countersink, based on dimensionality of said first precision countersink in said generated composite image; and

feeding back said positional and process refinement parameters to provide adaptive control of said one or more numerically controlled mechanisms.

2. The method according to claim 1, comprising:

collecting at least a second image from a second camera of a second precision countersink of the component, said second precision countersink being a bottom countersink of a hole and said first precision countersink being a top countersink of said hole, wherein;

said second camera comprises a second lens and is attached to and housed within said housing, and wherein said second lens is circumferentially shielded by a first end portion of a second elongate hollow tube that extends from said housing in a direction parallel to said first elongate hollow tube, said second elongate hollow tube further comprising a second end portion that comprises a second mirror and a second opening facing said first opening;

said first camera is in a first position and operates in one or more luminance environments; and

said second camera is in a second position and operates in an alternative lighting environment to differentiate characteristic features including hole and countersink against their intersection with the surface of the component.

3. The method according to claim 2, wherein said alternative lighting environment is configured to improve contrast of one or more irregular marks on one or more walls of the component.

4. The method according to claim 2, comprising activating at least one spectral light source during a first of said one or more luminance environments, wherein said at least one spectral light source enables characterizing and revealing presence or absence of at least one of spectral behavior, concavity, and convexity in an object space in a field of view of said first camera.

5. The method according to claim 4, wherein said at least one spectral light source is disposed axially or orbitally in relation to a central axis of said first camera.

6. The method according to claim 4, comprising activating at least one circumferential light source during a second of said one or more luminance environments, wherein said at least one circumferential light source comprises a plurality of louvered spectral light sources, said plurality of louvered spectral light sources disposed at an acute angle in relation to said object space in said field of view of said first camera.

7. The method according to claim 6, comprising activating at least one diffuse louvered direct light source during a third of said one or more luminance environments, wherein said at least one diffuse louvered direct light source is operable to flood said object space in said field of view of said first camera with direct, diffuse light to overcome ambient light sources and mute contrast in machine textured surfaces.

8. The method according to claim 1, wherein said adaptive control of said one or more of the numerically controlled mechanisms comprises compensating for one or more of dimensional drift, cutter wear, surface abnormality and part distortions.

9. A method for inspecting a component, the method comprising:

deploying a first camera in a first position above and outside of a first precision countersink within the component, wherein said first camera comprises a first lens and is attached to and housed within a housing, and wherein said first lens is circumferentially shielded by a first end portion of a first elongate hollow tube that extends from said housing, said first elongate hollow tube further comprising a second end portion that comprises a first mirror and a first opening;

deploying a second camera in a second position below and outside of said first precision countersink, wherein said second camera comprises a second lens and is attached to and housed within said housing, and wherein said second lens is circumferentially shielded by a first end portion of a second elongate hollow tube that extends from said housing in a direction parallel to said first elongate hollow tube, said second elongate hollow tube further comprising a second end portion that comprises a second mirror and a second opening facing said first opening;

collecting at least a first plurality of images from said first camera of said first precision countersink of the component, wherein said first camera operates in a plurality of luminance environments provided by a plurality of light sources each positioned outside of said first precision countersink; and

generating at least one combined image of said first precision countersink based on said collected at least said first plurality of images, wherein said at least one combined image is superimposed with at least one indicator quantifying compliance of said first precision countersink to one or more technical specifications.

10. The method according to claim 9, comprising:

collecting at least a second plurality of images from said second camera of a second precision countersink of the component, wherein said second camera operates in an alternative lighting environment;

generating at least a second combined image of said second precision countersink based on said collected at least said second plurality of images, wherein said at least said second combined image is superimposed with at least one indicator quantifying compliance of said second precision countersink to said one or more technical specifications,

wherein said first camera and said second camera are deployed simultaneously to a top and a bottom surface of the component, respectively.

11. The method according to claim 10, comprising locating, during said deploying of said first and second cameras, a hole associated with said first and second precision countersinks, wherein said locating uses backlighting provided within said alternative lighting environment.

12. The method according to claim 11, wherein said backlighting uses at least one translational light source and/or at least one diffuse louvered direct light source associated with said second camera.

13. The method according to claim 9, comprising collecting a plurality of images of said first precision countersink or a component surface surrounding said first precision countersink using one or more combinations of a translational light source, a circumferential light source and a diffuse louvered direct light source associated with said first camera.

14. The method according to claim 13, comprising:

performing an initial determination of normality of a central axis of a field of view of said first camera in relation to said component surface surrounding said first precision countersink, based on said collected plurality of images; and

classifying, based on said collected plurality of images, said component surface surrounding said first precision countersink as one of;

a primed/painted surface, a shot-peened surface, a sanded surface, a sand-blasted surface, and a machined/polished surface.

15. The method according to claim 14, comprising, if said component surface surrounding said first precision countersink is one of:

a primed/painted surface, a shot-peened surface, a sanded surface, and a sand-blasted surface, finalizing said initial determination of normality using a structured shape light projector associated with said first camera.

16. The method according to claim 9, comprising activating at least one spectral light source during a first of said plurality of luminance environments, wherein said at least one spectral light source enables characterizing and revealing presence or absence of spectral behavior, concavity, and convexity in an object space in a field of view of said first camera.

17. The method according to claim 16, wherein said at least one spectral light source is disposed axially or orbitally in relation to a central axis of said first camera.

18. The method according to claim 16, comprising activating at least one circumferential light source during a second of said plurality of luminance environments, wherein said at least one circumferential light source comprises a plurality of louvered spectral light sources, said plurality of louvered spectral light sources disposed at an acute angle in relation to said object space in said field of view of said first camera.

19. The method according to claim 18, comprising activating at least one diffuse louvered direct light source during a third of said plurality of luminance environments, wherein said at least one diffuse louvered direct light source is operable to flood the object space in said field of view of said first camera with direct, diffuse light to overcome ambient light sources and mute contrast in machine textured surfaces.

20. A method for measuring dimensionality of a component, the method comprising:

collecting at least a first plurality of images from a first and second camera of a precision countersink of an aircraft component, wherein said first camera comprises a first lens and is attached to and housed within a housing, and wherein said first lens is circumferentially shielded by a first end portion of a first elongate hollow tube that extends from said housing, said first elongate hollow tube further comprising a second end portion that comprises a first mirror and a first opening, and wherein said second camera comprises a second lens and is attached to and housed within said housing, and wherein said second lens is circumferentially shielded by a first end portion of a second elongate hollow tube that extends from said housing in a direction parallel to said first elongate hollow tube, said second elongate hollow tube further comprising a second end portion that comprises a second mirror and a second opening facing said first opening, and wherein said first and second elongate hollow tubes are independently operable to produce a plurality of luminance environments for said precision countersink, each of said plurality of luminance environments being associated with activation of a different type of light source, to differentiate characteristic features including hole and countersink against their intersection with the component;

calculating positional and process refinement parameters for one or more numerically controlled mechanisms, based on a composite image generated using said collected at least said first plurality of images, said composite image being generated by superimposing said collected at least said first plurality of images; and

feeding back said positional and process refinement parameters to provide adaptive control of said one or more numerically controlled mechanisms.

21. The method according to claim 20, wherein said adaptive control of said one or more numerically controlled mechanisms comprises compensating for one or more of dimensional drift, cutter wear, surface abnormality and part distortions.

22. The method according to claim 20, wherein said plurality of luminance environments is configured to improve contrast of one or more irregular marks on one or more walls of the component.

23. The method according to claim 20, comprising activating at least one spectral light source during a first of said plurality of luminance environments, wherein said at least one spectral light source enables characterizing and revealing presence or absence of at least one of spectral behavior, concavity, and convexity in an object space in a field of view of said camera.

24. The method according to claim 23, wherein said at least one spectral light source is disposed axially or orbitally in relation to a central axis of said camera.

25. The method according to claim 23, comprising activating at least one circumferential light source during a second of said plurality of luminance environments, wherein said at least one circumferential light source comprises a plurality of louvered spectral light sources, said plurality of louvered spectral light sources disposed at an acute angle in relation to said object space in said field of view of said camera.

26. The method according to claim 25, comprising activating at least one diffuse louvered direct light source during a third of said plurality of luminance environments, wherein said at least one diffuse louvered direct light source is operable to flood said object space in said field of view of said periscopic camera with direct, diffuse light to overcome ambient light sources and mute contrast in machine textured surfaces.