Apparatus and method for 3-dimensional surface geometry reconstruction

• US 6,167,151 A
• Filed: 12/11/1997
• Issued: 12/26/2000
• Est. Priority Date: 12/15/1996
• Status: Expired due to Fees

• Current Assignee: CogniTens Ltd. (Hexagon AB)
• Original Assignee: CogniTens Ltd. (Hexagon AB)
• Inventors: Shashua, Amnon, Benady, Meny, Albeck, Dan, Shalom, Tamir, Zelnik, Ilan, Yosef, Eyal, Rudich, Arie
• Primary Examiner(s): MEHTA, BHAVESH M
• Application Number:
  US08/989,047
• Time in Patent Office: 1,111 Days
• Field of Search: 382/103, 382/108, 382/154, 382/282, 382/284, 382/294, 382/153, 345/419, 345/420, 345/425, 345/430, 348/412, 348/47-48, 348/580, 348/584, 356/2, 356/376
• US Class Current: 382/154
• CPC Class Codes: G06T 17/00 Three dimensional [3D] modelling, e.g. data description of 3D objects
• CPC Class Codes: G06T 17/10 Constructive solid geometry [CSG] using solid primitives, e.g. cylinders, cubes
• CPC Class Codes: G06T 3/08 Projecting images onto non-planar surfaces, e.g. geodetic screens
• CPC Class Codes: G06V 10/16 using multiple overlapping images; Image stitching
• CPC Class Codes: G06V 10/24 Aligning, centring, orientation detection or correction of the image
• CPC Class Codes: G06V 20/64 Three-dimensional objects
• CPC Class Codes: G06V 2201/08 Detecting or categorising vehicles

Abstract

A system for reconstructing the surface geometry of an object includes a three-view optic head, a mechanical manipulator, a local 3D surface geometry reconstruction unit and a surface geometry stitching unit. The three-view optic head is operative to generate at least three views of at least a portion of the object. The mechanical manipulator is operative to vary the relative orientation of the object and the optic head, at a precision less than the a predetermined degree of precision, from a first relative orientation in which a first portion of the object is visible to at least one second relative orientation in which a second portion of the object, which overlaps the first portion, is visible. The local 3D surface geometry reconstruction unit is operative to generate local reconstructions of the surface geometries of the first and second portions of the object, based on at least two of three views of the first and second portions generated by the optic head. The surface geometry stitching unit is operative to determine the relative locations of the first and second portions of the object.

Claims

1. A 3D surface geometry reconstruction system for reconstructing the surface geometry of an object to a given degree of precision, the system comprising:

a three-view optic head operative to generate at least three views of at least a portion of the object;

a mechanical manipulator operative to vary the relative orientation of the object and the optic head, at a precision less than said given degree of precision, from a first relative orientation in which a first portion of the object is visible to at least one second relative orientation in which a second portion of the object, which overlaps said first portion, is visible;

a local 3D surface geometry reconstruction unit operative to reconstruct the surface geometry of said first and second portions of the object, based on at least two of three views of said first and second portions generated by said optic head; and

a surface geometry stitching unit operative to determine the relative locations of said first and second portions of the objects.

2. A system according to claim 1 wherein said mechanical manipulator comprises an object manipulator operative to move the object.

3. A system according to claim 1 wherein said mechanical manipulator comprises an optic head manipulator operative to move the optic head.

4. A system according to claim 1 wherein said three views generated by said optic head include two views on which 3D surface geometry reconstruction is based and a third view from which a tensor is computed which represents the internal orientation of each of said three views and the relative orientation of the three views.

5. A system according to any of the preceding claims wherein said object includes:

a first section of the object seen in one of said three views;

a second section of the object seen in another of said three views; and

an overlap section of the object which is included in said first section and said second section; and

wherein said 3D surface geometry reconstruction unit comprises an overlap texture analyzer operative to analyze texture of a section of said second portion which overlaps said first portion thereby to determine the relative locations of said first and second portions.

6. A system according to claim 5 wherein said texture comprises surface texture of the object.

7. A system according to claim 5 wherein said texture comprises a texture applied to the object.

8. A system according to claim 7 wherein said texture is projected onto said object.

9. A system according to claim 8 comprising a plurality of speckle generators each projecting a random speckle pattern onto the object.

10. A system according to claim 9 wherein each of said speckle generators comprises a diffuser on which a speckle pattern is generated and through which light is projected to project the speckle pattern from the diffuser onto a portion of said object.

11. A system according to claim 10 wherein each of said speckle generators comprise a laser diode which directs laser light via a lens onto said diffuser.

12. A system according to claim 10 wherein said diffuser is a holographic diffuser.

13. A system according to claim 8 wherein said texture is a speckle pattern projected onto said object.

14. A system according to claim 13 comprising a plurality of speckle generators each projecting a random speckle pattern onto the object.

15. A system according to claim 14 wherein each of said speckle generators comprises a diffuser on which a speckle pattern is generated and through which light is projected to project the speckle pattern from the diffuser onto a portion of said object.

16. A system according to claim 15 wherein each of said speckle generators comprise a laser diode which directs laser light via a lens onto said diffuser.

17. A system according to claim 15 wherein said diffuser is a holographic diffuser.

18. A system according to claim 5 wherein said texture does not vary as a result of variation in the relative orientation of the object and the optic head.

19. A system according to claim 1 wherein the mechanical manipulator provides a plurality of relative orientations of the object and the optical head such that the entire surface of the object is imaged by the optical head and wherein said surface geometry stitching unit is operative to reconstruct the entire surface of the object.