Range-finding based image processing rail way servicing apparatus and method

• US 6,647,891 B2
• Filed: 12/13/2001
• Issued: 11/18/2003
• Est. Priority Date: 12/22/2000
• Status: Active Grant

• Current Assignee: Norfolk Southern Corporation
• Original Assignee: Norfolk Southern Corporation
• Inventors: Lowe, Gregory, McCubbrey, David, Holmes, Quentin, Samson, Joseph, Rendleman, Robert, Kortesoja, Paul, Blanchfield, John, Witter, Lester, Wessling, Thomas
• Primary Examiner(s): Morano, S. Joseph
• Assistant Examiner(s): Olson, Lars A.
• Application Number:
  US10/013,530
• Publication Number:
  US 20020078853A1
• Time in Patent Office: 705 Days
• Field of Search: 104/2, 104/7.1, 104/7.2, 104/12, 104/17.1, 250/559.33, 250/559.31, 250/559.46, 250/559.23, 250/237.G, 356/602, 356/603, 356/604, 356/608
• US Class Current: 104/2
• CPC Class Codes: E01B 27/00 Placing, renewing, working, cleaning, or taking-up the ballast, with or without concurrent work on the track; Devices therefor; Packing sleepers
• CPC Class Codes: E01B 29/00 Laying, rebuilding, or taking-up tracks; Tools or machines therefor E01B27/00, E01B31/00 take precedence
• CPC Class Codes: E01B 31/00 Working rails, sleepers, baseplates, or the like, in or on the line; Machines, tools, or auxiliary devices specially designed therefor characterised by features independent of use on assembled track B21, B23 - B25, B27
• CPC Class Codes: E01B 35/00 Applications of measuring apparatus or devices for track-building purposes apparatus on locomotives or cars to indicate or record bad track sections B61K9/00; measuring angles, linear dimensions, or irregularities in general G01B, G01C

Abstract

A method and an apparatus for identifying a feature of a railway and deploying equipment for servicing same by image processing range data pertaining to the railway feature. The method includes identifying a feature of a railway, wherein the identifying involves processing an image corresponding to ranges to the feature. The apparatus includes a vision system for determining a range to a feature of the railway and means for positioning equipment relative to, for servicing, the feature, based on the range.

Claims

1. A method of servicing a railway, said method comprising:

identifying a feature of a railway based upon a range measurement from a vision system to the feature being identified, said vision system employing light infrared detection and ranging;

irradiating the feature by at least one laser beam emitted by at least one laser emitter;

sensing energy radiated from the feature due to said irradiation by said laser beam by at least one infrared sensor;

transmitting at least one signal corresponding to a property of said sensed energy;

comparing a property of said emitted laser beam to said transmitted signal for three-dimensional identification of the feature;

processing a three-dimensional image of the feature based upon the range measurement; and

servicing the railway.

2. Method of claim 1, wherein said identifying comprises establishing correspondence between the image and data pertaining to a predicted image of the feature.

3. Method of claim 1, further comprising verifying the feature.

4. Method of claim 3, wherein said verifying comprises:

locating an inflection point on the image indicative of an attribute of the feature;

ascertaining a slope at the inflection point; and

determining whether the slope falls within a predetermined range.

5. Method of claim 4, further comprising:

measuring a distance from the inflection point to another attribute of the feature; and

determining whether the distance falls within a predetermined range.

6. Method of claim 4, further comprising:

measuring a height of the inflection point; and

determining whether the height falls within a predetermined range.

7. Method of claim 3, wherein said verifying comprises:

extracting range values for each pixel of a plurality of columns of pixels of the image;

determining average range values across each row across the columns;

determining slopes between the average range values;

locating an inflection point indicative of an attribute of the feature from the slopes;

ascertaining a slope at the inflection point; and

determining whether the slope falls within a predetermined range.

8. Method of claim 7, further comprising:

measuring a distance from the inflection point to another attribute of the feature; and

determining whether the distance falls within a predetermined range.

9. Method of claim 7, further comprising:

measuring a height of the inflection point; and

determining whether the height falls within a predetermined range.

10. Method of claim 1, further comprising positioning equipment relative to, for servicing, the feature based on said identifying.

11. Method of claim 10, wherein said positioning comprises ascertaining a range to a fiducial point of the equipment.

12. Method of claim 10, wherein said positioning comprises determining a differential range between a current position and a position associated with the feature.

13. Method of claim 10, wherein:

the equipment is mounted on a carriage that is moveable relative to the railway; and

said positioning comprises instructing equipment positioning means to move the equipment, instructing carriage positioning means to move the carriage or combinations thereof.

14. Method of claim 1, further comprising positioning a carriage carrying equipment relative to, for servicing, the feature based on said identifying.

15. Method of claim 14, further comprising positioning the equipment relative to the carriage based on said identifying.

16. A method of servicing a railway, said method comprising:

locating a feature of a railway based upon a range measurement from a vision system the feature being located, said vision system employing light infrared detection and ranging;

irradiating the feature by at least one laser beam emitted by at least one laser emitter;

sensing energy radiated from the feature due to said irradiation by said laser beam by at least one infrared sensor;

transmitting at least one signal corresponding to a property of said sensed energy;

comparing a property of said emitted laser beam to said transmitted signal for three-dimensional identification of the feature;

positioning a carriage carrying equipment relative to, for servicing, the feature based on said locating;

identifying a three-dimensional attribute of the feature; and

positioning the equipment with respect to the carriage relative to the attribute based on one or both of said locating and said identifying.

17. Method of claim 16, further comprising servicing the attribute with the equipment.

18. Method of claim 16, wherein one or both of said locating and said identifying comprises establishing correspondence between an actual image of the feature or attribute and data pertaining to a predicted image thereof.

19. Method of claim 18, wherein the actual image is based on range data.

20. Method of claim 16, further comprising verifying the feature.

21. Method of claim 20, wherein said verifying comprises:

locating an inflection point on an image of the feature which is indicative of an attribute of the feature;

ascertaining a slope at the inflection point; and

determining whether the slope falls within a predetermined range.

22. Method of claim 21, wherein the image is based on range data.

23. Method of claim 21, further comprising:

measuring a distance from the inflection point to another attribute of the feature; and

determining whether the distance falls within a predetermined range.

24. Method of claim 21, further comprising:

measuring a height of the inflection point; and

determining whether the height falls within a predetermined range.

25. Method of claim 20, wherein said verifying comprises:

extracting range values for each pixel of a plurality of columns of pixels of an image of the feature;

determining average range values across each row across the columns;

determining slopes between the average range values;

locating an inflection point indicative of an attribute of the feature;

ascertaining a slope at the inflection point; and

determining whether the slope falls within a predetermined range.

26. Method of claim 25, further comprising:

measuring a distance from the inflection point to another attribute of the feature; and

determining whether the distance falls within a predetermined range.

27. Method of claim 25, further comprising:

measuring a height of the inflection point; and

determining whether the height falls within a predetermined range.

28. Method of claim 16, further comprising verifying the attribute.

29. Method of claim 28, wherein said verifying comprises:

locating an inflection point on an image of the attribute which is indicative of an predetermined point of the attribute;

ascertaining a slope at the inflection point; and

determining whether the slope falls within a predetermined range.

30. Method of claim 29, wherein the image is based on range data.

31. Method of claim 29, further comprising:

measuring a distance from the inflection point to another predetermined point of the attribute; and

determining whether the distance falls within a predetermined range.

32. Method of claim 29, further comprising:

measuring a height of the inflection point; and

determining whether the height falls within a predetermined range.

33. Method of claim 28, wherein said verifying comprises:

extracting range values for each pixel of a plurality of columns of pixels of an image of the attribute;

determining average range values across each row across the columns;

determining slopes between the average range values;

locating an inflection point indicative of a predetermined point of the attribute;

ascertaining a slope at the inflection point; and

determining whether the slope falls within a predetermined range.

34. Method of claim 33, further comprising:

measuring a distance from the inflection point to another predetermined point of the attribute; and

determining whether the distance falls within a predetermined range.

35. Method of claim 33, further comprising:

measuring a height of the inflection point; and

determining whether the height falls within a predetermined range.

36. Method of claim 16, further comprising positioning equipment relative to, for servicing, the feature based on one or both of said locating and said identifying.

37. Method of claim 36, wherein said positioning comprises ascertaining a range to a fiducial point of the equipment.

38. Method of claim 36, wherein said positioning comprises determining a differential range between a current position and a position associated with the feature.

39. Method of claim 36, wherein:

the equipment is mounted on a carriage that is moveable relative to the feature; and

said positioning comprising instructing equipment positioning means to move the equipment, instructing carriage positioning means to move the carriage or combinations thereof.

40. Method of claim 16, further comprising positioning a carriage carrying equipment relative to, for servicing, the feature based on one or both of said locating and said identifying.

41. Method of claim 40, further comprising positioning the equipment relative to the carriage based on one or both of said locating and said identifying.

42. Apparatus for servicing a railway, said apparatus comprising:

a vision system for determining a range from said vision system to a feature of the railway, said vision system being capable of three-dimensional identification of the feature and employing light infrared detection and ranging;

at least one laser emitter for emitting at least one laser beam for irradiating the feature;

at least one infrared sensor for sensing energy radiated from the feature due to said irradiation by said laser beam;

at least one transmitter for transmitting at least one signal corresponding to a property of said sensed energy;

a system for comparing a property of said emitted laser beam to said transmitted signal for three-dimensional identification of the feature;

means for positioning equipment relative to, for servicing, the feature, based on the range determination by said vision system; and

means for identifying a three-dimensional attribute of the feature.

43. Apparatus of claim 42, wherein

said system including an image processor for comparing the phase expressed by said transmitted signal with a phase of said laser beam and generating a range signal corresponding to the range,

wherein said means for identifying being a sensor for sensing energy originating from the feature and generating a signal expressing the phase of the energy.

44. Apparatus of claim 42, further comprising a carriage for carrying said vision system and said means for positioning equipment.

45. Apparatus of claim 44, wherein said means for positioning equipment comprises carriage positioning means for moving the carriage relative to the railway, equipment positioning means for moving the equipment relative to said carriage, or combinations thereof.

46. Apparatus of claim 42, further comprising equipment for servicing the railway operably connected to said means for positioning.

47. Apparatus of claim 46, wherein the equipment comprises a tie tamper, a spiking gun, a rail anchor adjuster, a rail anchor spreader, a Pandrol screw machine, a Pandrol clip applicator, a tie drilling machine, liquid tie plugging equipment or combinations thereof.

48. Apparatus of claim 42, wherein said vision system comprises:

means for identifying all four sides of a spike hole; and

means for directing motion of a spike gun both along a track and across a track.