Portable coordinate measurement machine with integrated line laser scanner

• US 7,519,493 B2
• Filed: 06/20/2007
• Issued: 04/14/2009
• Est. Priority Date: 02/14/2002
• Status: Expired due to Term

• Current Assignee: Faro Technologies Incorporated
• Original Assignee: Faro Technologies Incorporated
• Inventors: Barba, Jacint R., Atwell, Paul Christopher, York, Frederick
• Primary Examiner(s): Bui; Bryan
• Application Number:
  US11/765,726
• Publication Number:
  US 20070294045A1
• Time in Patent Office: 664 Days
• Field of Search: 702/95, 702150-152, 702/155, 702/159, 356/4.02, 356/5.01, 335/03, 335/56, 335/59, 335/61, 700/56, 700/59, 700/61, 382/254, 382/279, 358/412, 358/486
• US Class Current: 702/95
• CPC Class Codes: G01B 11/005 coordinate measuring machines
• CPC Class Codes: G01B 21/042 Calibration or calibration artifacts G01B3/30, G01B9/02072 take precedence
• CPC Class Codes: G01B 5/012 Contact-making feeler heads therefor
• CPC Class Codes: G01C 25/00 Manufacturing, calibrating, cleaning, or repairing instruments or devices referred to in the other groups of this subclass testing, calibrating or compensating compasses G01C17/38

Abstract

A portable coordinate measurement machine for measuring the position of an object in a selected volume comprises includes an a positionable articulated arm having a plurality of jointed arm segments. The arm includes a measurement probe having an integrated line laser scanner mounted thereon. The laser may be a fiber coupled laser. Wireless data transfer and communication capability for the CMM is also possible.

Claims

1. A portable coordinate measurement machine (CMM) for measuring the position of an object in a selected volume, comprising:

a manually positionable articulated arm having opposed first and second ends, said arm including a plurality of jointed arm segments, each arm segment including at least one position transducer for producing a position signal;

a fiber coupled laser scanner at said first end of said arm;

an electronic circuit which receives the position signals from the transducers and provides a digital coordinate corresponding to the position of the first end of said arm in a selected volume; and

at least one internally positioned bus within said articulated arm for internally transmitting at least one of power and data signals to said fiber coupled laser scanner, said fiber coupled laser scanner including circuitry communicating with said at least one bus.

2. The CMM of claim 1 further comprising:

at least one attenuator located to reduce the width of a laser line emitted from the fiber coupled laser scanner.

3. The CMM of claim 1 further comprising:

at least one clear window mounted on the fiber coupled laser scanner.

4. The CMM of claim 1 further comprising:

a handle extending from said first end of said arm.

5. The CMM of claim 1 wherein said first end of said arm includes three degrees of freedom and wherein one of said three degrees of freedom is a rotation axis for rotating said fiber coupled laser scanner.

6. The CMM of claim 5 wherein said CMM includes three additional degrees of freedom such that said jointed arm segments have degrees of freedom in a 2-1-3 configuration.

7. The CMM of claim 5 wherein said CMM includes four additional degrees of freedom such that said jointed arm segments have degrees of freedom in a 2-2-3 configuration.

8. The CMM of claim 1 wherein said at least one bus comprises a serial communications bus and wherein said fiber coupled laser scanner is connected to said bus.

9. The CMM of claim 8 wherein said serial communications bus is RS-485 type.

10. The CMM of claim 1 wherein:

said fiber coupled laser scanner is detachably mounted onto said first end of said arm.

11. The CMM of claim 1 further comprising:

a kinematic mount for detachably mounting said fiber coupled laser scanner to said first end of said arm.

12. The CMM of claim 1 wherein said fiber coupled laser scanner includes a scanner housing for housing a laser and a camera, said housing being mounted to said first end of said arm.

13. The CMM of claim 12 wherein said scanner housing is permanently mounted to said first end of said arm.

14. The CMM of claim 12 wherein said scanner housing is detachably mounted to said first end of said arm.

15. The CMM of claim 12 wherein at least said laser and camera are mounted on a low CTE frame.

16. The CMM of claim 15 wherein said low CTE frame comprise a steel/nickel alloy.

17. The CMM of claim 16 wherein said steel/nickel alloy comprises Invar.

18. The CMM of claim 1 wherein said fiber coupled laser scanner further comprises:

a digital interface communicating with said camera;

a digital signal processor (DSP) communicating with said digital interface for processing images from said scanner;

a memory communicating with said DSP; and

a communications processor communicating with said DSP.

19. The CMM of claim 17 wherein said digital interface comprises:

a high speed data communications interface for communicating between said camera and said digital interface.

20. The CMM of claim 17 wherein:

said high speed data communications interface uses a Firewire data format.

21. The CMM of claim 1 wherein said at least one bus transmits both power and data signals.

22. The CMM of claim 1 wherein said arm includes circuitry for simultaneously transmitting data from said transducers and from said fiber coupled laser scanner to a host computer.

23. The CMM of claim 1 wherein said fiber coupled laser scanner includes on-board image processing circuitry which converts image data to dimensional data.

24. The CMM of claim 21 wherein said dimensional data is transferred using said at least one bus.

25. The CMM of claim 16 wherein said DSP includes on-board image processing circuitry which converts image data to dimensional data.

26. The CMM of claim 1 wherein said fiber coupled laser scanner includes on-board image processing circuitry which generates processed data, such processed data being in an amount which is smaller than the amount of data associated with the original data derived from the image received from said camera.

30. The CMM of claim 1 wherein said fiber coupled laser scanner includes a wireless antenna for sending data via wireless.

33. The CMM of claim 1 wherein said fiber coupled laser scanner includes multiple laser scanners in one overall unit.

36. The CMM of claim 1 wherein said fiber coupled laser scanner includes a bracket made of AlSi.

39. The CMM of claim 1 wherein said fiber coupled laser scanner includes a removable laser mount.

27. A portable coordinate measurement machine (CMM) for measuring the position of an object in a selected volume, comprising:

a manually positionable articulated arm having opposed first and second ends, said arm including a plurality of jointed arm segments, each arm segment including at least one position transducer for producing a position signal;

a fiber coupled laser scanner at said first end of said arm;

at least one clear window mounted on the fiber coupled laser scanner;

an electronic circuit which receives the position signals from the transducers and provides a digital coordinate corresponding to the position of the first end of said arm in a selected volume; and

at least one internally positioned bus within said articulated arm for internally transmitting at least one of power and data signals to said fiber coupled laser scanner, said fiber coupled laser scanner including circuitry communicating with said at least one bus;

wherein

said fiber coupled laser scanner includes at least one attenuator located to reduce the width of a laser line emitted from the laser.

28. The CMM of claim 27 wherein said fiber coupled laser scanner includes at least one attenuator located to reduce the width of a laser line emitted from the laser.

31. The CMM of claim 27 wherein said fiber coupled laser scanner includes a wireless antenna for sending data via wireless.

34. The CMM of claim 27 wherein said fiber coupled laser scanner includes multiple laser scanners in one overall unit.

37. The CMM of claim 27 wherein said fiber coupled laser scanner includes a bracket made of AlSi.

40. The CMM of claim 27 wherein said fiber coupled laser scanner includes a removable laser mount.

29. A method for calibrating a coordinate measurement machine (CMM) for measuring the position of an object, comprising:

digitizing a calibration plate using a ball probe, and also using a fiber coupled laser line scanner which are both attached to the CMM comprising;

touching the ball probe to an area of the calibration plate and digitizing a plurality of reference points on the surface;

calculating the flatness of the surface from the position of the reference points;

aiming the fiber coupled laser line scanner at the center of the surface of the calibration plate in relation to the plurality of reference points;

rotating the laser line scanner 90° and

aiming the fiber coupled laser line scanner at the center of the surface of the calibration plate in relation to the plurality of reference points;

aiming the laser line scanner at the center of the surface of the calibration plate in relation to the plurality of reference points and moving the fiber coupled laser line scanner towards the surface to a range close to the surface of the calibration plate; and

moving the fiber coupled laser line scanner away from the surface of the calibration plate while pointing to the center of the surface; and

calculating calibration points for fiber coupled laser line scanner from the position of the reference points in relation to the fiber coupled laser scanner aiming ad rotating steps performed above; and

updating a stored probe calibration status of the ball probe.

32. The CMM of claim 29 wherein said fiber coupled laser scanner includes a wireless antenna for sending data via wireless.

35. The CMM of claim 29 wherein said fiber coupled laser scanner includes multiple laser scanners in one overall unit.

38. The CMM of claim 29 wherein said fiber coupled laser scanner includes a bracket made of AlSi.

41. The CMM of claim 29 wherein said fiber coupled laser scanner includes a removable laser mount.

42. A portable coordinate measurement machine (CMM) for measuring the position of an object in a selected volume, comprising:

a manually positionable articulated arm having opposed first and second ends, said arm including a plurality of jointed arm segments, each arm segment including at least one position transducer for producing a position signal;

a laser scanner at said first end of said arm;

an electronic circuit which receives the position signals from the transducers and provides a digital coordinate corresponding to the position of the first end of said arm in a selected volume; and

at least one internally positioned bus within said articulated arm for internally transmitting at least one of power and data signals to said laser scanner, said laser scanner including circuitry communicating with said at least one bus; and

said laser scanner including a wireless antenna for communicating data to and from said laser scanner to reduce data sent over the bus.

43. The CMM of claim 42 wherein said laser scanner includes multiple laser scanners in one overall unit.

44. The CMM of claim 42 wherein said laser scanner includes a bracket made of AlSi.

45. The CMM of claim 42 wherein said laser scanner includes a removable laser mount.