METHOD AND DEVICE FOR MEASURING FEATURES ON OR NEAR AN OBJECT

• US 20160196643A1
• Filed: 02/08/2016
• Published: 07/07/2016
• Est. Priority Date: 03/04/2011
• Status: Active Grant

• Current Assignee: Baker Hughes, a GE Company, LLC (Baker Hughes Company)
• Original Assignee: General Electric Company
• Inventors: Bendall, Clark Alexander
• Granted Patent: US 9,984,474 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G01B 11/24 for measuring contours or curvatures
• CPC Class Codes: G06F 3/005 Input arrangements through a video camera
• CPC Class Codes: G06F 3/04845 for image manipulation, e.g. dragging, rotation, expansion or change of colour
• CPC Class Codes: G06T 19/00 Manipulating 3D models or images for computer graphics
• CPC Class Codes: G06T 2200/04 involving 3D image data
• CPC Class Codes: G06T 2200/24 involving graphical user interfaces [GUIs]
• CPC Class Codes: G06T 2207/10028 Range image; Depth image; 3D point clouds
• CPC Class Codes: G06T 2207/10068 Endoscopic image
• CPC Class Codes: G06T 2207/20101 Interactive definition of point of interest, landmark or seed
• CPC Class Codes: G06T 2207/30136 Metal
• CPC Class Codes: G06T 2207/30164 Workpiece; Machine component
• CPC Class Codes: G06T 2210/41 Medical
• CPC Class Codes: G06T 2219/012 Dimensioning, tolerancing
• CPC Class Codes: G06T 2219/028 Multiple view windows (top-side-front-sagittal-orthogonal)
• CPC Class Codes: G06T 7/0004 Industrial image inspection
• CPC Class Codes: G06T 7/50 Depth or shape recovery
• CPC Class Codes: G06T 7/62 of area, perimeter, diameter or volume

Abstract

A method and device for measuring dimensions of a feature on or near an object using a video inspection device. A reference surface is determined based on reference surface points on the surface of the object. One or more measurement cursors are placed on measurement pixels of an image of the object. Projected reference surface points associated with the measurement pixels on the reference surface are determined. The dimensions of the feature can be determined using the three-dimensional coordinates of at least one of the projected reference surface points.

Claims

1. A method for measuring a feature on or near a viewed object, the method comprising the steps of:

displaying on a monitor an image of the viewed object;

determining the three-dimensional coordinates of a plurality of points on a surface of the viewed object using a central processor unit;

selecting one or more reference surface points from the plurality of points on the surface of the viewed object using a pointing device;

determining a reference surface using the central processor unit, wherein the reference surface is determined based on the one or more of the reference surface points;

placing one or more measurement cursors on one or more measurement pixels of the image using a pointing device;

determining one or more projected reference surface points associated with the one or more measurement cursors on the reference surface using the central processor unit, wherein each of the one or more projected reference surface points are determined based on the intersection of a three-dimensional trajectory line from the one or more measurement pixels and the reference surface; and

determining the dimensions of the feature on or near the viewed object using the three-dimensional coordinates of at least one of the one or more projected reference surface points using the central processor unit.

2. The method of claim 1, wherein the image of the viewed object is a two-dimensional image.

3. The method of claim 1, wherein the reference surface is a plane.

4. The method of claim 1, wherein the step of selecting one or more reference surface points using a pointing device is performed by placing reference surface cursors on each of the reference surface points.

5. The method of claim 1, further comprising the step of displaying on the monitor a three-dimensional view of the plurality of points on the surface of the viewed object and the one or more projected reference surface points on the reference surface.

6. The method of claim 1, wherein at least one of the one or more projected reference surface points is associated with a measurement pixel not having associated three-dimensional coordinates of a point on the surface of the viewed object.

7. The method of claim 1, wherein at least one of the one or more projected reference surface points is associated with a measurement pixel having associated three-dimensional coordinates of a point on the surface of the viewed object.

8. The method of claim 7, wherein the step of determining the dimensions of the feature on or near the viewed object using the three-dimensional coordinates of at least one of the one or more projected reference surface points further comprises using the three-dimensional coordinates of at least one of the plurality of points on the surface of the viewed object.

9. The method of claim 1, wherein the reference surface is determined based on the three-dimensional coordinates of the one or more of the reference surface points or the three-dimensional coordinates of surface points proximate one or more of the reference surface points.

10. The method of claim 1, wherein the feature on or near the viewed object is a missing corner of the viewed object, and wherein the step of placing one or more measurement cursors on one or more measurement pixels of the image using a pointing device comprises performing an area measurement by

placing a first measurement cursor on a first edge of the viewed object proximate the missing corner at a first distance from the reference surface points,

placing a second measurement cursor on a second edge of the viewed object proximate the missing corner at a second distance from the reference surface points, and

placing a third measurement cursor at a third distance from the reference surface points.

11. The method of claim 10, further comprising the steps of:

determining that the third distance is greater than the first distance and the second distance;

determining an angle between (i) a first line extending between the first measurement cursor and the third measurement cursor and (ii) a second line extending between the second measurement cursor and the third measurement cursor using a central processor unit; and

if the angle is within a predetermined range of angles, automatically determining the area formed by the measurement cursors and the length of the first line and the second line.

12. The method of claim 10, further comprising the steps of:

determining the lengths of a first line extending between the first measurement cursor and the third measurement cursor and a second line extending between the second measurement cursor and the third measurement cursor using a central processor unit; and

displaying on the monitor the dimensions of the area formed by the measurement cursors and the lengths of the first line and the second line.

13. The method of claim 10, further comprising the steps of displaying on the monitor a first extension line extending from the third measurement cursor through the first measurement cursor along the first edge of the viewed object and a second extension line extending from the third measurement cursor through the second measurement cursor along the second edge of the viewed object.

14. The method of claim 1, further comprising the steps of:

determining a distance between a point on the surface of the viewed object and the reference surface using the central processor unit;

comparing the distance to a predetermined distance threshold using the central processor unit; and

displaying an overlay on a pixel in the two-dimensional image associated with the point on the surface of the viewed object if the distance is below the predetermined distance threshold.

15. The method of claim 14, wherein the distance is the perpendicular distance between the point on the surface of the viewed object and the reference surface.

16. The method of claim 1, further comprising the steps of:

determining a distance between a point on the surface of the viewed object and the reference surface using a central processor unit;

comparing the distance to a predetermined distance threshold using the central processor unit; and

displaying in a three-dimensional view of the plurality of points on the surface of the viewed object an indication of the surface point having a distance below the predetermined distance threshold.

17. The method of claim 1, further comprising the steps of:

displaying on the monitor a three-dimensional view of the plurality of points on the surface of the viewed object; and

displaying on the three-dimensional view a plurality of field of view lines extending from a field of view origin to provide a visual indication of the orientation of a tip of a probe of a video inspection device with respect to the viewed object.

18. The method of claim 1, further comprising the steps of:

displaying on the monitor a three-dimensional view of the plurality of points on the surface of the viewed object and the reference surface; and

displaying a guideline on the three-dimensional view extending from one of the one or more projected reference surface points associated with the one or more measurement cursors on the reference surface to a point on the surface of the viewed object, wherein the guideline is perpendicular to the reference surface.

19. The method of claim 1, wherein the reference surface is a reference plane, further comprising the steps of:

determining an edge view plane based on the three-dimensional coordinates associated with at least two of the measurement cursors placed on an edge of an object using the central processor unit;

determining an angle between the reference plane and the edge view plane using the central processor unit; and

if the angle is outside of a predetermined range of angles, indicating a warning on the monitor.