Method and apparatus for single-axis cross-sectional scanning of parts

• US 9,324,129 B2
• Filed: 05/15/2009
• Issued: 04/26/2016
• Est. Priority Date: 05/19/2008
• Status: Active Grant

• Current Assignee: Craig D. Crump
• Original Assignee: Craig D. Crump
• Inventors: Crump, Craig D., Kahler, Brad, Braegelman, Dan
• Primary Examiner(s): Geisel, Kara E
• Assistant Examiner(s): BOLOGNA, DOMINIC JOSEPH
• Application Number:
  US12/993,525
• Publication Number:
  US 20110069300A1
• Time in Patent Office: 2,538 Days
• Field of Search: 356/36, 356601-613
• US Class Current: 1/1
• CPC Class Codes: G01N 1/286 involving mechanical work, e.g. chopping, disintegrating, compacting, homogenising microtomes G01N1/06; pulverising in general B02C; mixing in general B01F
• CPC Class Codes: G01N 2001/061 Blade details
• CPC Class Codes: G01N 2001/366 Moulds; Demoulding
• CPC Class Codes: G06T 17/10 Constructive solid geometry [CSG] using solid primitives, e.g. cylinders, cubes
• CPC Class Codes: G06T 3/00 Geometric image transformations in the plane of the image

Abstract

Improved methods and apparatus for cross-sectional scanning of parts employ a scanning station in which the focal plane of the scanning apparatus never moves in the vertical direction, i.e., the direction in which the stage of the part/potting combination moves. Distinct steps of material removal and scanning alternate with an intermediate step of moving the part/potting combination in the vertical direction after a surface layer has been removed, thus placing the newly-created surface back into the non-moving focal plane for the next scanning step. A removal station (not the stage carrying the part/potting combination) repeatedly moves into and out of the field of view of the scanning station between scanning steps. The material removal station is specially configured to remove the desired surface layer of the part/potting combination and the created debris, without requiring the separate environment characteristic of previous commercial applications.

Claims

1. A system for scanning a part having an outer surface, the system comprising:

a data gathering station;

a material removal station including a vacuum, a hood, and a cutting tool that rotates about a Y-axis; and

a table providing only vertical, Z-axis movement of the part relative to the data gathering station along a vertical path,

wherein the part is encased in a potting material to form an assembly, wherein the material removal station is configured to move horizontally in an X-axis perpendicular to the Y-axis proximate the assembly to remove a thin and consistent portion of the assembly to expose a surface and the vacuum is arranged and configured to collect the removed portion of the assembly, and wherein the cutting tool has a cutting length in the Y-direction greater than an assembly width in the Y-direction.

2. The system of claim 1, in which the data gathering station comprises at least one of:

an image data acquisition device for successively acquiring images of the part after removal of a predetermined contour; and

an electronic device operatively associated with the image data acquisition device for receiving and storing the images.

3. The system of claim 1, in which the material removal station further comprises a drive mechanism constructed and arranged to provide relative horizontal movement between the tool and the part.

4. The system of claim 1, in which the table holds the part and further comprises a drive mechanism constructed and arranged to provide vertical movement between the table and the data gathering station along the vertical path.

5. The system of claim 1, wherein the cutting tool includes at least one blade configured to rotate on a rotary surface, the rotary surface making tangential contact with the assembly such that a direction of travel at the point of tangential contact is opposite a direction of travel of the material removal station.

6. A method for producing electronic data representations of an object having a plurality of surfaces, the method comprising:

encasing the object within a preselected encasing material to form an encasement, such encasing being done so that all surfaces of the object are coated with the encasing material and so that the encasing material substantially fills all interior volumes of the object;

removing successively from the encasement, by a cutting tool that rotates about a Y-axis, a plurality of thin and consistent layers of material, each layer of material removed having predetermined dimensions of length, width and depth and a predetermined geometric shape, so as to expose an encasement surface, and assigning a value to each layer representative of its elevation within the object, the cutting tool having a cutting length in the Y-direction greater than an encasement width in the Y-direction;

vacuuming debris created from removing the plurality of layers by horizontal X-axis movement of a vacuum proximate the encasement surface;

acquiring an electronic representation of selected exposed encasement surfaces after each layer has been removed and the debris is vacuumed; and

processing each electronic representation to create a predetermined electronic representation of each the encasement surface.

7. The method of claim 6, in which the selected electronic representation is a solid model of the object and in which the processing step includes converting each electronic representation into a layered point cloud representative of the object.

8. The method of claim 7, in which the method further comprises lofting a surface onto each layered point cloud.

9. The method of claim 6, in which the method further comprises importing each layer into CAD space and stacking the layers according to their assigned elevation value.

10. The method of claim 6, and further including creating a solid between adjacent layers.

11. The method of claim 6, in which the selected electronic representation is a solid model of the object.

12. The method of claim 6, in which the selected electronic representation is a surface model of the object.

13. The method of claim 6, in which the layer removing step removes contour of material such that successively exposed surfaces of the object are substantially parallel to each other, the method further including:

identifying a feature of interest in the object; and

orienting the object such that the exposed surfaces of the object are non-parallel to the feature of interest so that at least one exposed surface extends through the feature of interest.

14. The method of claim 6, in which the selected electronic representation is a surface model of the object and in which the processing step includes convening each electronic representation into a line art drawing defining the perimeter edges of the internal and external edges of the object.

15. The method of claim 14, in which the processing step further includes stacking the line art drawings and lofting a surface thereon.

16. The method of claim 14, in which the processing step further includes converting the line art drawings into a vector data file.

17. The method of claim 16, in which the processing step further includes importing the vector data file into 3D CAD space and lofting a surface thereon.

18. The method of claim 6, in which the layers have upper and lower surfaces and a substantially uniform thickness, the upper and lower surfaces being substantially parallel to each other.

19. The method of claim 6, in which the electronic representation is a raster planar image and in which the processing step further includes importing the raster planar image into 3D CAD space and converting the imported images into a solid model of the object.

20. The method of claim 6, in which the layers have upper and lower surfaces being substantially parallel to each other and in which the layers increase in thickness as successive layers of the encasement are removed to form each the predetermined contour.

21. The method of claim 6, in which the layers have upper and lower surfaces being substantially parallel to each other and in which the layers decrease in thickness as successive layers of the encasement are removed to form each the predetermined contour.

22. The method of claim 6, in which the predetermined contour has a substantially uniform thickness of about one thousandth of one inch.

23. The method of claim 6, wherein the cutting tool includes at least one blade configured to rotate on a rotary surface, the rotary surface making tangential contact with the encasement such that a direction of travel at the point of tangential contact is opposite a direction of travel of the vacuum.

24. An apparatus for producing electronic data representations of an object, the object being formed from at least one material, the apparatus comprising:

a material removal station having a mill having a cutting tool that rotates about a Y-axis, a vacuum, and a hood, the material removal station for removing a thin and consistent predetermined layer of material from the object, the cutting tool having a cutting length in the Y-direction greater than an object width in the Y-direction;

a data gathering station having an image data acquisition device for successively imaging the object after removal of a predetermined layer, the image data acquisition device having a fixed position focal plane;

a stage movable in only a vertical direction along a vertical Z-axis perpendicular to the fixed position focal plane; and

a device for storing data gathered by the image data acquisition device, wherein

the stage comprises;

a table for holding the object, wherein the table is moved only in a single direction to maintain the object in imaging alignment with the image data acquisition device before and after the mill moves into and out of position proximate the object for removing the predetermined layer of material, and

wherein the material removal station moves in an X-axis direction substantially perpendicular to the Z-axis into and out of relative material removing position in which the material removal station removes and collects the predetermined layer of material.

25. The apparatus of claim 24, in which the data gathering station is capable of producing a three-dimensional drawing of the object.

26. The apparatus of claim 24, in which the object is encased within an encasing material to form an encasement and in which the mill removes a predetermined layer of the encasement.

27. The apparatus of claim 24, in which the mill comprises an end mill including at least one flute, the end mill being rotated about an axis substantially perpendicular to the axis of motion of the stage and substantially parallel to the common plane, such that a planar surface of the object is exposed by the removal of material by at least one flute as the end mill is rotated.

28. The apparatus of claim 24, in which the removal of the predetermined layer of material exposes an object surface and an encasing material surface and in which the object surface contrasts with the encasing material surface so that a line of demarcation may be determined between the surfaces.

29. The apparatus of claim 24, in which the predetermined layer of material is of substantially uniform thickness.

30. The apparatus of claim 24, wherein the cutting tool includes at least one blade configured to rotate on a rotary surface, the rotary surface making tangential contact with the object such that a direction of travel at the point of tangential contact is opposite a direction of travel of the material removal station.

31. A method of scanning a part, comprising:

encasing the part into a potting material to form an assembly;

while the assembly is not moving, progressively horizontally removing, by a cutting tool that rotates about a Y-axis, a thin and consistent portion of the assembly to expose a surface, the cutting tool having a cutting length in the Y-direction greater than an assembly width in the Y-direction;

vacuuming the removed portion away from the assembly by horizontal X-axis movement perpendicular to the Y-axis of a vacuum proximate the surface;

moving the surface substantially only vertically along a Z-axis to a position in a fixed position focal plane; and

scanning the surface.

32. The method of claim 31, further comprising repeating progressively horizontally removing, by a cutting tool that rotates about a Y-axis, a portion of the assembly to expose a surface and moving the surface substantially only vertically along a Z-axis to a position in a fixed position focal plane after scanning the surface.

33. The method of claim 31, wherein the cutting tool includes at least one blade configured to rotate on a rotary surface, the rotary surface making tangential contact with the assembly such that a direction of travel at the point of tangential contact is opposite a direction of travel of the vacuum.

34. A system for scanning an object, wherein the object is encased in potting material to form a potting assembly prior to scanning, the system comprising:

a data gathering station including an image data acquisition device that gathers data from a focal plane;

a material removal station including a rotating end mill that rotates about a Y-axis, a vacuum and a hood, the end mill having a cutting length in the Y-direction greater than a potting assembly width in the Y-direction; and

a stage on which the potting assembly is secured,

wherein the stage moves toward the data gathering station on a fixed line transverse to the focal plane,

wherein the system provides for selectively changing a distance between the object, when the object is encased in a potting assembly and secured to the stage, and the data gathering station along the fixed line,

wherein the material removal station repeatedly removes a series of thin and consistent pre-determined portions of the potting assembly to expose a new surface on the potting assembly that is positioned in the focal plane as the stage moves toward the data gathering station when the object is encased in the potting assembly and secured to the stage, and

wherein the stage moves only along a Z-axis, the image data acquisition device is stationary and the material removal station moves proximate and distal the potting assembly only along an X-axis perpendicular to the Z-axis.

35. The system of claim 34, wherein the image data acquisition device successively acquires images of the potting assembly after removal of the predetermined portions, in which the data gathering station further includes an electronic device operatively associated with the image data acquisition device for receiving and storing the images.

36. The system of claim 34, in which the material removal station further includes a drive mechanism constructed and arranged to provide relative movement between the tool and the potting assembly.

37. The system of claim 34, wherein the fixed line is vertical and the stage further includes a drive mechanism constructed and arranged to provide vertical movement between the stage and the data gathering station along the vertical fixed line.

38. The system of claim 34, wherein the rotating end mill includes at least one blade configured to rotate on a rotary surface, the rotary surface making tangential contact with the potting assembly such that a direction of travel at the point of tangential contact is opposite a direction of travel of the material removal station.

39. An apparatus for producing electronic data representations of an object, the object being formed from at least one material, the apparatus comprising:

a material removal station;

a data gathering station having a fixed position focal plane; and

a stage movable in only a Z direction along a Z-axis, perpendicular to the fixed position focal plane;

wherein the material removal station includes;

a vacuum and a hood, and a tool for removing a predetermined layer of material from the object, the tool configured to rotate about a Y-axis, the tool having a cutting length in the Y-direction greater than an object width in the Y-direction;

wherein the data gathering station includes;

an image data acquisition device for successively imaging the object after removal of a predetermined layer; and

data storage device for storing gathered by the image data acquisition device for imaging; and

wherein the stage includes;

a table for holding the object;

wherein the table moves only in a single direction to maintain the object in imaging alignment with the image data acquisition device for successively imaging the object before and after the tool is moved into and out of position for removing a layer of material; and

wherein the material removal station moves only substantially perpendicular to the Z-axis in an X-axis into and out of relative material removing position proximate the object in which the material removal station removes and collects a thin and consistent predetermined layer of material.

40. The apparatus of claim 39, in which the data gathering station further includes means for manipulating data gathered by the image data acquisition device and stored in the data storage device to produce a three-dimensional drawing of the object.

41. The apparatus of claim 39, in which the object is encased within an encasing material to form an encasement and in which the tool removes a predetermined layer of the encasement.

42. The apparatus of claim 39, in which the material removal station further includes an end mill including at least one tool, the end mill being rotated about an axis substantially perpendicular to the axis of motion of the stage such that a planar surface of the object is exposed by the removal of material by at least one tool as the end mill is rotated.

43. The apparatus of claim 39, in which the removal of the predetermined layer exposes an object surface and an encasing material surface and in which the object surface contrasts with the encasing material surface so that a line of demarcation may be determined between the surfaces.

44. The apparatus of claim 39, in which the predetermined layer is of substantially uniform thickness.

45. The apparatus of claim 39, in which the data gathering station further includes means for manipulating data gathered by the imaging and stored in the data storage device to produce a three-dimensional drawing of the object.

46. A method of scanning an object, the method comprising:

(a) encasing the object into a potting material to form a potting assembly;

(b) while the potting assembly is not moving, progressively removing, with a material removal station including a cutting tool that rotates about a Y-axis, a thin and consistent portion of the potting assembly to expose a surface, the cutting tool having a cutting length in the Y-direction greater than an object width in the Y-direction;

(c) vacuuming the removed portions of the potting assembly by X-axis movement perpendicular to the Y-axis of the material removal station;

(d) moving the potting assembly with a stage substantially only vertically along a Z-axis to a position in a fixed position focal plane; and

(e) scanning the surface with an image data acquisition device,

wherein the stage moves only along a Z-axis, the image data acquisition device is stationary, and the material removal station moves proximate and distal the potting assembly only along an X-axis perpendicular to the Z-axis.

47. The method of claim 46, further comprising repeating (b) and (c) after (d) after (e).

48. A method of producing electronic data representations of an object, the object having a plurality of surfaces, wherein the method comprises:

providing a system for scanning the object, wherein the object is encased in potting material to form a potting assembly prior to scanning, the system comprising;

a data gathering station including an image data acquisition device that gathers data from a focal plane, a material removal station including a cutting tool that rotates about a Y-axis, the cutting tool having a cutting length in the Y-direction greater than a potting assembly width in the Y-direction, and a stage on which the potting assembly is secured;

wherein the stage moves toward the data gathering station in a Z-axis on a fixed line transverse to the focal plane;

wherein the system provides for selectively changing a distance between the object, when the object is encased in a potting assembly and secured to the stage, and the data gathering station along the fixed line;

wherein the material removal station repeatedly removes a series of thin and consistent pre-determined portions of the potting assembly to expose a new surface on the potting assembly that is positioned in the focal plane as the stage moves toward the data gathering station when the object is encased in the potting assembly and secured to the stage;

encasing the object within a preselected encasing material to form a potting assembly, such encasing being done so that all of the plurality of surfaces of the object are coated with the encasing material and so that the encasing material substantially fills all interior volumes of the object;

removing successively from the encasement, by the cutting tool, a plurality of layers of material, each layer of material removed having predetermined dimensions of length, width and depth and a predetermined geometric shape, so as to expose an encasement surface, and assigning a value to each layer representative of its elevation within the object;

vacuuming the removed layers of material by horizontal X-axis movement perpendicular to the Y-axis of a vacuum proximate the encasement surface;

acquiring an electronic representation of selected exposed encasement surfaces after a predetermined layer has been removed; and

processing each electronic representation to create a predetermined electronic representation of each encasement surface.

49. The method of claim 48, wherein the selected electronic representation is a three dimensional point cloud representative of the object.

50. The method of claim 48, in which the selected electronic representation selected from the group consisting of a solid model of the object and a surface model of the object.

51. The method of claim 48, wherein the acquiring step includes scanning each encasement surface using a scanner to create a scanned image of each encasement surface.

52. The method of claim 48,

wherein the removing step includes removing a contour of material such that successively exposed encasement surfaces of the object are substantially parallel to each other, the method further comprising:

identifying a feature of interest in the object; and

orienting the object such that the exposed encasement surfaces of the object are non-parallel to the feature of interest so that at least one exposed encasement surface extends through the feature of interest.

53. The method of claim 48, wherein the layers have upper and lower encasement surfaces and a substantially uniform thickness, the upper and lower surfaces being substantially parallel to each other.