Two-camera triangulation scanner with detachable coupling mechanism

Patent metadata

Field	Value
Publication number	US-10866089-B2
Application number	US-201916552276-A
Country	US
Kind code	B2
Filing date	Aug 27, 2019
Priority date	Apr 24, 2015
Publication date	Dec 15, 2020
Grant date	Dec 15, 2020

Abstract

A three-dimensional (3D) scanner having two cameras and a projector is detachably coupled to a device selected from the group consisting of: an articulated arm coordinate measuring machine, a camera assembly, a six degree-of-freedom (six-DOF) tracker target assembly, and a six-DOF light point target assembly.

First claim

What is claimed is:

1. A method for measuring three-dimensional (3D) coordinates of an object surface comprising:
providing a processor;
providing a target device including a triangulation scanner and a six degree-of-freedom (six-DOF) target assembly, the triangulation scanner including a projector, a scanner camera, and a scanner connector, the six-DOF target assembly including a collection of light points and an assembly connector configured to detachably couple to the scanner connector;
providing a camera bar device including a first camera and a second camera separated by a camera-bar baseline distance, the first camera and the second camera fixed in space;
connecting the scanner connector to the assembly connector;
in a first instance:
projecting with the projector a first light onto the object surface;
forming with the scanner camera a first image of the first light and sending a first electrical scan signal to the processor in response;
forming with the first camera a first light point image of the collection of light points and sending a first electrical light point signal to the processor in response;
forming with the second camera a second light point image of the collection of light points and sending a second electrical light point signal to the processor in response;
determining by the camera bar device in cooperation with the processor and a six-DOF target assembly first values for six degrees of freedom of the triangulation scanner;
determining with the processor the 3D coordinates of the object surface based at least in part on the first light, the first electrical scan signal, the first electrical light point signal, and the second electrical light point signal; and
storing the 3D coordinates of the object surface.

2. The method of claim 1 further comprising:
in a second instance:
projecting with the projector a second light onto the object surface;
forming with the scanner camera a second image of the second light and sending a second electrical scan signal to the processor in response;
forming with the first camera a third light point image of the collection of light points and sending a third electrical light point signal to the processor in response;
forming with the second camera a fourth light point image of the collection of light points and sending a fourth electrical light point signal to the processor in response; and
determining with the processor the 3D coordinates of the object surface further based on the second light, the second electrical scan signal, the third electrical light point signal, and the fourth electrical light point signal.

3. The method of claim 1 wherein, in the step of providing the target device including the triangulation scanner and the six degree-of-freedom (six-DOF) target assembly, the triangulation scanner is a laser line probe.

4. The method of claim 1 wherein, in the step of providing the target device including the triangulation scanner and the six degree-of-freedom (six-DOF) target assembly, the triangulation scanner is an area scanner.

5. The method of claim 1 wherein the processor is further configured to determine the 3D coordinates of the object surface based at least in part on a scanner baseline distance between the scanner camera and the projector.

6. The method of claim 1 wherein the step of providing the processor, the triangulation scanner, and the six degree-of-freedom (six-DOF) tracker target assembly further includes providing a tactile probe.

7. A method for measuring three-dimensional (3D) coordinates of a tactile probe comprising:
providing a processor;
providing a target device including a triangulation scanner and a six degree-of-freedom (six-DOF) target assembly, the triangulation scanner including a scanner connector, the six-DOF target assembly including a collection of light points, the tactile probe, and an assembly connector configured to detachably coupled to the scanner connector;
providing a camera bar device including a first camera and a second camera separated by a camera-bar baseline distance, the first camera and the second camera fixed in space;
connecting the scanner connector to the assembly connector;
forming with the first camera a first light point image of the collection of light points and sending a first electrical light point signal to the processor in response;
forming with the second camera a second light point image of the collection of light points and sending a second electrical light point signal to the processor in response; and
determining with the processor the 3D coordinates of an object surface based at least in part on the first electrical light point signal, and the second electrical light point signal, and the camera-bar baseline distance.

8. A system for measuring three-dimensional (3D) coordinates of an object surface comprising:
a processor;
a target device including a triangulation scanner and a six degree-of-freedom (six-DOF) target assembly, the triangulation scanner including a projector, a scanner camera, and a scanner connector, the projector configured to project a scanner pattern onto the object surface, the scanner camera configured to form an image of the scanner pattern and to send an electrical scanner signal to the processor in response, the six-DOF target assembly including a collection of light points and an assembly connector configured to detachably couple to the scanner connector;
a camera bar device including a first camera and a second camera separated by a camera-bar baseline distance, the first camera and the second camera fixed in space, the first camera configured to form a first light point image of the collection of light points and to send a first electrical light point signal to the processor in response, the second camera configured to form a second light point image of the collection of light points and to send a second electrical light point signal to the processor in response,
wherein the processor is configured to determine the 3D coordinates of the object surface based at least in part on the scanner pattern, the electrical scanner signal, the first electrical light point signal, the second electrical light point signal, and the camera-bar baseline distance.

9. The system of claim 8 wherein the processor is further configured to determine the 3D coordinates of the object surface based at least in part on a scanner baseline distance between the scanner camera and the projector.

10. The system of claim 8 wherein the triangulation scanner is a laser line probe.

11. The system of claim 10 wherein the projector is configured to project a line of light.

12. The system of claim 8 wherein the triangulation scanner is an area scanner.

13. The system of claim 12 wherein the projector is configured to project light to cover an area on the object surface.

14. The system of claim 8 wherein the six-DOF target assembly further includes a tactile probe configured to measure 3D coordinates of points on the object surface.

15. The system of claim 8 wherein the scanner connector is further configured to detachably couple to a first connector of an articulated arm coordinate measurement machine.

16. The system of claim 8 further comprising a battery.

17. The system of claim 8 further comprising a color camera configured to produce a color image, the color camera configured to produce an electrical signal of the color image, the processor being configured to add color to the 3D coordinates of the object surface based at least in part on the electrical signal of the color image.

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Assignees

• Faro Tech Inc

Inventors

• Tohme Yazid
• Heidemann Rolf
• Grau Markus
• Bridges Robert E

Classifications

• H04N1/60

  Colour correction or control {(H04N1/54 takes precedence)} · CPC title

• G01B11/2545 Primary

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

• G06F3/0412

  Digitisers structurally integrated in a display · CPC title

• G01B11/25

  by projecting a pattern, e.g. {one or more lines,} moiré fringes on the object (G01B11/255 takes precedence {; image analysis for depth or shape recovery G06T7/50}) · CPC title

• H04N13/239

  using two two-dimensional [2D] image sensors having a relative position equal to or related to the interocular distance (H04N13/243 takes precedence) · CPC title