HAND-HELD SELF-REFERENCED APPARATUS FOR THREE-DIMENSIONAL SCANNING

• US 20100134598A1
• Filed: 12/02/2009
• Published: 06/03/2010
• Est. Priority Date: 03/11/2005
• Status: Active Grant

• Current Assignee: Creaform, Inc. (Ametek Incorporated)
• Original Assignee: Creaform, Inc. (Ametek Incorporated)
• Inventors: CARON, Antoine Thomas, BEAUPRÉ, Nicolas, GAGNÉ, Pierre-Luc, ST-PIERRE, Éric, TUBIC, Dragan, HÉBERT, Patrick
• Granted Patent: US 8,082,120 B2
• Time in Patent Office: Days
• US Class Current: 348/47
• CPC Class Codes: G01B 11/2513 with several lines being projected in more than one direction, e.g. grids, patterns
• CPC Class Codes: G01C 11/02 Picture taking arrangements specially adapted for photogrammetry or photographic surveying, e.g. controlling overlapping of pictures

Abstract

A method and hand-held scanning apparatus for three-dimensional scanning of an object is described. The hand-held self-referenced scanning apparatus has a light source for illuminating retro-reflective markers, the retro-reflective markers being provided at fixed positions on or around the object, a photogrammetric high-resolution camera, a pattern projector for providing a projected pattern on a surface of the object; at least a pair of basic cameras, the basic camera cooperating with light sources, the projected pattern and at least a portion of the retro-reflective markers being apparent on the 2D images, a frame for holding all components in position within the hand-held apparatus, the frame having a handle, the frame allowing support and free movement of the scanning apparatus by a user.

Claims

1. A hand-held self-referenced scanning apparatus for three-dimensional scanning of an object, said hand-held scanning apparatus comprising:

a first light source for illuminating at least one marker of a set of retro-reflective markers, wherein each marker of said set of retro-reflective markers is provided at a fixed position one of on and near said object, said first light source being adapted to illuminate said marker at a photogrammetric modeling distance of more than 75 cm to said object;

a photogrammetric high-resolution camera for acquiring and storing at least one photogrammetric image of said object, said photogrammetric high-resolution camera cooperating with said first light source, wherein at least a portion of said set of retro-reflective markers is apparent on said photogrammetric image, said photogrammetric high-resolution camera being adapted to acquire said photogrammetric image at said photogrammetric modeling distance;

a pattern projector for providing a projected pattern on a surface of said object;

at least a pair of second light sources, each said second light sources for illuminating at least one marker of said set of retro-reflective markers, said second light source being adapted to illuminate said marker at a surface scanning distance of less than 60 cm from said object;

at least a pair of basic cameras for acquiring and storing 2D images of said object, one 2D image from each basic camera, each said basic camera cooperating with one of said second light sources, wherein said projected pattern and at least a portion of said set of retro-reflective markers is apparent on said 2D images, a spatial relationship between said pair of basic cameras being known, said basic cameras being adapted to acquire said 2D images at said surface scanning distance;

a frame for holding in position said first light source, said photogrammetric high-resolution camera, said pattern projector, said basic cameras and said at least a pair of second light sources within said hand-held apparatus, said frame having a handle, said frame allowing support and free movement of said scanning apparatus by a user;

whereby said user may freely handle said hand-held self-referencing scanning apparatus to build a 3D model of said markers and then obtain dense sets of 3D surface points from said 2D images.

2. The hand-held self-referenced scanning apparatus as claimed in claim 1, further comprising a control circuit for controlling operation of said first light source, said photogrammetric high-resolution camera, said pattern projector, said at least said pair of second light sources and said at least said pair of basic cameras, said control circuit being mounted to said frame.

3. The hand-held self-referenced scanning apparatus as claimed in claim 1, wherein said frame is adapted to allow single-handed handling of said scanning apparatus.

4. The hand-held self-referenced scanning apparatus as claimed in claim 1, further comprising a casing for said scanning apparatus, said casing protecting said frame, said photogrammetric high-resolution camera, said pattern projector, said basic cameras and said at least a pair of second light sources and providing said handle.

5. The hand-held self-referenced scanning apparatus as claimed in claim 1, wherein said first light source is coaxial with said photogrammetric camera.

6. The hand-held self-referenced scanning apparatus as claimed in claim 1, wherein said second light source is coaxial with said basic camera.

7. The hand-held self-referenced scanning apparatus as claimed in claim 1, wherein said first light source is a ring light source surrounding said photogrammetric high-resolution camera.

8. The hand-held self-referenced scanning apparatus as claimed in claim 1, wherein said at least two second light sources are ring light sources each surrounding one of said at least a pair of cameras.

9. The hand-held self-referenced scanning apparatus as claimed in claim 2, further comprising switches for actuating said controller.

10. The hand-held self-referenced scanning apparatus as claimed in claim 9, wherein said switches are provided at separate locations on said frame.

11. The hand-held self-referenced scanning apparatus as claimed in claim 7, wherein said first light source is a ring having at least two Light Emitting Diodes (LED).

12. The hand-held self-referenced scanning apparatus as claimed in claim 8, wherein said second light sources are rings each having at least two Light Emitting Diodes (LED).

13. The hand-held self-referenced scanning apparatus as claimed in claim 1, wherein said pattern projector is a laser pattern projector and wherein said projected pattern is a laser pattern.

14. The hand-held self-referenced scanning apparatus as claimed in claim 13, wherein said laser pattern projector projects a laser crosshair pattern on said object.

15. The hand-held self-referenced scanning apparatus as claimed in claim 2, further comprising at least one status indicator activated by said controller for indicating a status of said scanning apparatus.

16. The hand-held self-referenced scanning apparatus as claimed in claim 1, further comprising a hub for handling transmission of said 2D images and said photogrammetric image.

17. The hand-held self-referenced scanning apparatus as claimed in claim 1, wherein said photogrammetric modeling distance is 1.75 m.

18. The hand-held self-referenced scanning apparatus as claimed in claim 1, wherein said 3D scanning distance is 30 cm.

19. The hand-held self-referenced scanning apparatus as claimed in claim 1, wherein said frame has two perpendicular axes, said basic cameras being provided at opposite ends of one of said two perpendicular axes, said pattern projector and said photogrammetric camera being provided at opposite ends of another one of said two perpendicular axes, said basic cameras, said pattern projector, said photogrammetric camera all facing a same direction.

20. A method for three-dimensional scanning of an object, comprising:

obtaining at least one photogrammetric image of said object from a hand-held self-referenced scanning apparatus having;

a first light source for illuminating at least one marker of a set of retro-reflective markers, wherein each marker of said set of retro-reflective markers is provided at a fixed position one of on and near said object, said first light source being adapted to illuminate said marker at a photogrammetric modeling distance of more than 75 cm to said object;

a photogrammetric high-resolution camera for acquiring and storing at least one photogrammetric image of said object, said photogrammetric high-resolution camera cooperating with said first light source, wherein at least a portion of said set of retro-reflective markers is apparent on said photogrammetric image, said photogrammetric high-resolution camera being adapted to acquire said photogrammetric image at said photogrammetric modeling distance;

a pattern projector for providing a projected pattern on a surface of said object;

at least a pair of second light sources, each said second light sources for illuminating at least one marker of said set of retro-reflective markers, said second light source being adapted to illuminate said marker at a surface scanning distance of less than 45 cm from said object;

at least a pair of basic cameras for acquiring and storing 2D images of said object, one 2D image from each basic camera, each said basic camera cooperating with one of said second light sources, wherein said projected pattern and at least a portion of said set of retro-reflective markers is apparent on said 2D images, a spatial relationship between said pair of basic cameras being known, said basic cameras being adapted to acquire said 2D images at said surface scanning distance;

a frame for holding in position said first light source, said photogrammetric high-resolution camera, said pattern projector, said basic cameras and said at least a pair of second light sources within said hand-held apparatus, said frame having a handle, said frame allowing support and free movement of said scanning apparatus by a user;

extracting markers from said at least one photogrammetric images;

building a 3D model of said markers;

obtaining at least two 2D images of said object using said scanning apparatus;

positioning said at least two 2D images of said object in said 3D model of said markers;

extracting dense sets of 3D surface points from said at least two self-referenced 2D images;

whereby said user may freely handle said hand-held self-referencing scanning apparatus to build a 3D model of said markers and then obtain dense sets of 3D surface points from said 2D images.

21. The method as claimed in claim 20, further comprising detecting addition of additional retro-reflective markers on said object in said 2D images and updating said 3D model of markers to add said additional markers.

22. The method as claimed in claim 20, wherein said obtaining at least two 2D images is continuously repeated at predetermined rate once said obtaining is activated, while said scanning apparatus is in operation, wherein said scanning apparatus is displaced by said user while said scanning apparatus is in operation.

23. The method as claimed in claim 20, wherein said obtaining 2D images is performed on non-overlapping sections of said object.