Device for optically scanning and measuring an environment

Patent metadata

Field	Value
Publication number	US-9599455-B2
Application number	US-201313767154-A
Country	US
Kind code	B2
Filing date	Feb 14, 2013
Priority date	Dec 14, 2012
Publication date	Mar 21, 2017
Grant date	Mar 21, 2017

Abstract

A device for optically scanning and measuring an environment is provided. The device includes at least one projector for producing at least one uncoded pattern on an object in the environment. A first camera is provided for recording at least one first image of the object provided with the pattern, the first camera having a first image plane. A second camera is provided for recording at least one second image of the object provided with the uncoded pattern, the second camera being spaced apart from the first camera in order to acquire the uncoded pattern on a second image plane. A controller is provided having a processor configured to determine the three-dimensional coordinates of points on the surface of the object based at least in part on the uncoded pattern, the at least one first image and the at least one second image.

First claim

The invention claimed is:

1. A system for optically scanning and measuring an object in an environment, the system comprising:
a scanner device that includes a projector, a first camera, and a second camera,
the projector configured to project a first pattern of light from a projector plane, the first pattern of light being a first multivalued uncoded structured light pattern, the first pattern of light including a collection of illuminated points, the projector having a projector optical axis, each of the illuminated points having an identical shape,
the first camera configured to record in a first time instance a first image of the first multivalued pattern of light projected onto the object, the first image being recorded on a first image plane of the first camera, the first camera having a first camera optical axis,
the second camera configured to record in the first time instance a second image of the first multivalued pattern of light projected onto the object, the second image being recorded on a second image plane of the second camera, the second camera having a second camera optical axis,
the projector optical axis, the first camera optical axis, and the second camera optical axis are oriented in a non-collinear triangular arrangement,
each of the illuminated points on the projector plane, the first image plane, and the second image plane corresponding to and lying on an epipolar line in each of the other two of the projector plane, the first image plane, and the second image plane, the correspondence among epipolar lines and the illuminated points of the first pattern of light on the three planes determined by geometrical epipolar relations among the projector plane, the first image plane, and the second image plane; and
a processor configured to determine the correspondence among each of the illuminated points on the projector plane, the first image plane, and the second image plane, the correspondence determined at least in part by the geometrical epipolar relations among the three planes, the processor further configured to determine three-dimensional coordinates of each of the illuminated points on the object at the first time instance based at least in part on the illuminated points in the first multivalued pattern of light, the first image of the first multivalued pattern of light on the object, the second image of the first multivalued pattern of light on the object, and the geometry of the triangle.

2. The system of claim 1 wherein the collection of illuminated points includes at least three illuminated spots, each of the illuminated spots including a bright region surrounded by a dark region, each illuminated spot being unattached to any other illuminated spot.

3. The system of claim 2 wherein the collection of illuminated points further includes an illuminated line, the illuminated line including a continuous linear region of illumination.

4. The system of claim 1 wherein the collection of illuminated points includes a collection of illuminated spots falling on a regular grid pattern in the projector plane.

5. The system of claim 1 , wherein:
the projector includes a laser that emits a first wavelength to create the first pattern of light; and
the first camera and the second camera include bandpass filters that transmit at the first wavelength.

6. The system of claim 1 wherein the scanner device further comprises a third camera, the third camera being a color camera that records images of the object at visible wavelengths, the third camera being fixed on the scanner device.

7. The system of claim 1 , wherein the scanner device generates a second pattern of light, the second pattern of light being different than the first pattern of light, the second pattern of light being a second multivalued uncoded structured light pattern.

8. The system of claim 1 , wherein the projector includes an element from a group consisting of a diffractive optical element, a collection of microlenses, a plurality of single lasers, and a projected mask.

9. The system of claim 1 , wherein the processor is configured to select the first pattern of light from among a plurality of patterns of light.

10. The system of claim 9 wherein the scanner device is further configured to project a second pattern of light, the second pattern of light being offset with respect to time to the first pattern of light, the second pattern of light being a second uncoded pattern.

11. The system of claim 1 , wherein the first pattern of light further comprises a second pattern of light, the first pattern of light having a first optical wavelength and the second pattern of light having a second optical wavelength different than the first wavelength, the second pattern of light being a second uncoded pattern.

12. The system of claim 1 , wherein the scanner device further comprises a second projector, the second projector configured to project a second pattern of light different than the first pattern of light, the second pattern of light being a second multivalued uncoded structured light pattern.

13. The system of claim 1 wherein the scanner device is a handheld device.

14. The system of claim 1 , wherein the scanner device further comprises:
a base member, the projector being arranged in the base member;
a grip member protruding from the base member;
a trigger switch disposed on the grip member; and
a head end on an opposite end of the grip member from the base member, wherein the first camera and the second camera are disposed in the head end.

15. The system of claim 1 wherein the processor is an integral part of the scanner device.

16. The system of claim 1 , wherein the collection of illuminated points includes a first plurality of light points having a first intensity and a second pattern of light having a second plurality of light points having a second intensity different than the first intensity, wherein the first plurality of light points and the second plurality of light points each define a multivalued uncoded structured light pattern.

17. A system for optically scanning and measuring an object in an environment, the system comprising:
a scanner device that includes a projector, a first camera, and a second camera,
the projector configured to project a first pattern of light from a projector plane, the first pattern of light being a first multivalued uncoded structured light pattern, the first pattern of light including a collection of illuminated points, the projector having a projector optical axis,
the first camera configured to record in a first time instance a first image of the first multivalued pattern of light projected onto the object, the first image being recorded on a first image plane of the first camera, the first camera having a first camera optical axis,
the second camera configured to record in the first time instance a second image of the first multivalued pattern of light projected onto the object, the second image being recorded on a second image plane of the second camera, the second camera having a second camera optical axis,
the projector optical axis, the first camera optical axis, and the second camera optical axis are oriented in a non-collinear triangular arrangement,
each of the illuminated points on the projector plane, the first image plane, and the second image plane corresponding to and lying on an epipolar line in each of the other two of the projector plane, the first image plane, and the second image plane, the correspondence among epipolar lines and the illuminated points of the first pattern of light on the three planes determined by geometr

Assignees

• Faro Tech Inc

Inventors

• Heidemann Rolf
• Ossig Martin
• Becker Reinhard

Classifications

• G01B11/2531 Primary

  using several gratings, projected with variable angle of incidence on the object, and one detection device · CPC title

• G01B11/002 Primary

  for measuring two or more coordinates · CPC title

• G01B11/2545

  with one projection direction and several detection directions, e.g. stereo · CPC title

• G01B11/2513 Primary

  with several lines being projected in more than one direction, e.g. grids, patterns · CPC title

• G06T7/521

  from laser ranging, e.g. using interferometry; from the projection of structured light · CPC title