Laser-based dimensioning system

• US 5,850,370 A
• Filed: 02/11/1997
• Issued: 12/15/1998
• Est. Priority Date: 09/01/1989
• Status: Expired due to Fees

• Current Assignee: Quantronix Incorporated
• Original Assignee: Quantronix Incorporated
• Inventors: Stringer, Bradley J., Elwood, Michael K.
• Primary Examiner(s): Pihulic, Daniel T.
• Application Number:
  US08/798,569
• Time in Patent Office: 672 Days
• Field of Search: 367/128, 364/564, 356/379, 702/159, 342/54
• US Class Current: 367/128
• CPC Class Codes: G01B 11/00 Measuring arrangements characterised by the use of optical techniques
• CPC Class Codes: G01B 11/002 for measuring two or more coordinates
• CPC Class Codes: G01B 11/04 specially adapted for measuring length or width of objects while moving
• CPC Class Codes: G01B 17/00 Measuring arrangements characterised by the use of infrasonic, sonic or ultrasonic vibrations
• CPC Class Codes: G07B 2017/00685 Measuring the dimensions of mailpieces

Abstract

A method and apparatus for measuring the dimensions and determining the three-dimensional, spatial volume of objects, particularly small objects. Reflected laser light sensors are employed. A stationary measurement embodiment of the apparatus may be employed to measure regular cuboidal objects. A dynamic or in-motion embodiment may be employed to measure the dimensions of cuboidal objects or a three-dimensional outline of objects of irregular configuration.

Claims

1. An apparatus for measuring the length and width of an object, comprising:

at least one light sensor including an emitter for emitting a light beam and a receiver remote from said emitter and associated therewith for receiving a reflection of said light beam, said emitter being oriented to emit said light beam across a path of a linearly-moving object so that said light beam impinges upon said object;

said receiver including a light sensor for generating a signal responsive to receipt of said reflection of an associated light beam reflected from said object;

a device for detecting rate of speed of said object during impingement of said light beam thereon and generating a signal indicative of said rate of speed; and

a processor for computing the length and width of said object from said signals.

2. The apparatus of claim 1, wherein said at least one light sensor comprises two light sensors each having an emitter oriented to emit a light beam across the path of said linearly-moving object so that said light beams impinge upon said object, and wherein said processor is adapted to compute the length and width of said object from said signals.

3. The apparatus of claim 2, further including a device for detecting height of said object and generating a signal indicative of said height and wherein said processor is adapted to compute the height of said object from said signal from said height detecting device.

4. The apparatus of claim 3, wherein said processor is adapted to determine a volume of said object from said signals.

5. The apparatus of claim 1, further including a gain adjustment for adjusting intensity of said light beams responsive to the reflectivity of said object.

6. The apparatus of claim 1, wherein said at least one light sensor comprises a laser light sensor.

7. The apparatus of claim 6, wherein said emitter comprises a laser diode, and said receiver comprises a linear CCD array.

8. The apparatus of claim 7, wherein said emitter emits a light beam of elliptical cross-section, and said emitter is oriented to emit its said light beam with a long axis of said elliptical cross section substantially transverse to a direction of said linear CCD array.

9. The apparatus of claim 6, wherein said laser light is visible light.

10. The apparatus of claim 6, wherein said receiver further includes a light filter to filter out ambient light.

18. The apparatus of claim 3, wherein said height detecting device comprises an upright light curtain system disposed across said object path.

19. The apparatus of claim 18, wherein said processor is adapted to determine a volume of said object from said signals.

11. A method of measuring at least two dimensions of a three-dimensional object, comprising:

moving said object linearly along a path;

emitting a first light beam from a first fixed location on one side of said path against said object in substantially transverse orientation to movement of said object, and receiving said first light beam after reflection thereof from said object as said object moves, at a location displaced from said first fixed location;

determining a rate of speed of said object; and

computing said at least two dimensions from said rate of object speed and variations in position of receipt of said reflected first light beam at said receiving location.

12. The method of claim 11, further comprising emitting a second light beam against said object from a second fixed location in substantially transverse orientation to said movement of said object and receiving said second light beam after reflection thereof from said object as said object moves, at a location displaced from said second fixed location;

and

computing said at least two dimensions from said rate of object speed and variations in position of receipt of said reflected first and second light beams at said receiving locations.

13. The method of claim 12, further including determining the third dimension of said object, comprising emitting a third light beam against said object from a third fixed location in substantially transverse orientation to said movement of said object and above said path and receiving said third light beam after reflection thereof from said object at a location displaced from said third fixed location;

and

computing said third dimension from at least one position of receipt of said third light beam at said receiving location displaced from said third location.

14. The method of claim 13, further including determining a volume of said object from said three computed dimensions.

15. The method of claim 12, wherein said first and second light beams comprise laser light.

16. The method of claim 12, further including determining the third dimension of said object by detecting interruption of at least one of a plurality of mutually parallel light beams of an upright light curtain extending across the path of said object and computing said third dimension responsive to a number of light beams interrupted by said object moving through said light curtain.

17. The method of claim 16, further including determining a volume of said object from said three computed dimensions.

20. An apparatus for measuring length and width of an object, comprising:

at least one light sensor including an emitter for emitting a light beam and a receiver remote from said emitter and associated therewith for receiving a reflection of said light beam, said emitter being oriented to emit said light beam across a path of a linearly-moving object so that said light beam impinges upon said object;

said receiver including a light sensor for generating a signal responsive to receipt of said reflection of an associated light beam reflected from said object;

a device for detecting movement of said object during impingement of said light beam thereon and generating a signal indicative of said movement; and

a processor for computing the length and width of said object from said signals.

21. The apparatus of claim 20, wherein said at least one light sensor comprises two light sensors, each having an emitter oriented to emit a light beam across the path of said linearly-moving object so that said light beams impinge upon said object, and wherein said processor is adapted to compute the length and width of said object from said signals.

22. The apparatus of claim 21, further including a device for detecting height of said object and generating a signal indicative of said height and wherein said processor is adapted to compute the height of said object from said signal from said height detecting device.

23. The apparatus of claim 22, wherein said height detecting device comprises an upright light curtain system disposed across said object path.

24. The apparatus of claim 23, wherein said processor is adapted to determine a volume of said object from said signals.

25. The apparatus of claim 22, wherein said processor is adapted to determine a volume of said object from said signals.

26. The apparatus of claim 20, wherein said at least one light sensor comprises a laser light sensor.

27. The apparatus of claim 26, wherein said emitter comprises a laser diode, and said receiver comprises a linear CCD array.

28. The apparatus of claim 26, wherein said receiver further includes a light filter to filter out ambient light.

29. The apparatus of claim 20, further including a conveyor for effecting linear movement of said object along said path.

30. A method of measuring at least two dimensions of a three-dimensional object, comprising:

moving said object along a path;

emitting a first light beam from a first fixed location on one side of said path against said object in substantially transverse orientation to movement of said object, and receiving said first light beam after reflection thereof from said object as said object moves, at a location displaced from said first fixed location;

detecting said movement of said object; and

computing said at least two dimensions from said detected movement and variations in position of receipt of said reflected first light beam at said receiving location.

31. The method of claim 30, further comprising emitting a second light beam against said object from a second fixed location in substantially transverse orientation to the movement of said object and receiving said second light beam after reflection thereof from said object as said object moves, at a location displaced from said second fixed location;

and

computing said at least two dimensions from said detected object movement and variations in position of receipt of said reflected first and second light beams at said receiving locations.

32. The method of claim 31, further including determining the third dimension of said object, comprising emitting a third light beam against said object from a third fixed location in substantially transverse orientation to the movement of said object and above said path, and receiving said third light beam after thereof reflection from said object of a location displaced from said third fixed location;

and

computing said third dimension from at least one position of receipt of said third light beam at said receiving location displaced from said third location.

33. The method of claim 32, further including determining a volume of said object from said three computed dimensions.

34. The method of claim 31, wherein said first and second light beams comprise laser light.

35. The method of claim 31, further including determining the third dimension of said object by detecting interruption of at least one of a plurality of mutually parallel light beams of an upright light curtain extending across the path of said object and computing said third dimension responsive to a number of light beams interrupted by said object moving through said light curtain.

36. The method of claim 35, further including determining a volume of said object from said three computed dimensions.