Methods and system for determining shear angle

Patent metadata

Field	Value
Publication number	US-9880112-B2
Application number	US-201514821267-A
Country	US
Kind code	B2
Filing date	Aug 7, 2015
Priority date	Aug 7, 2015
Publication date	Jan 30, 2018
Grant date	Jan 30, 2018

Abstract

A method for determining an actual shear angle between an interior wall and a facesheet of a cellular panel using an imaging system is disclosed. The imaging system may include a radiation source and a detector diametrically opposed to the radiation source. The method may include positioning the cellular panel at a tilt angle relative to a line extending between the radiation source and the detector, transmitting radiation from the radiation source to the detector through the cellular panel at the tilt angle to obtain an image, measuring a projected shear angle in the obtained image, and determining the actual shear angle between the interior wall and the facesheet using the tilt angle and the projected shear angle.

First claim

What is claimed is:

1. A method for determining an actual shear angle between an interior wall and a facesheet of a cellular panel using an imaging system, the imaging system including a radiation source and a detector diametrically opposed to the radiation source, the method comprising:
positioning the cellular panel at a tilt angle relative to a line extending between the radiation source and the detector;
transmitting radiation from the radiation source to the detector through the cellular panel at the tilt angle to obtain an image;
measuring a projected shear angle in the obtained image;
determining the actual shear angle between the interior wall and the facesheet using the tilt angle and the projected shear angle; and
determining if the cellular panel is within predetermined specifications based on the determined actual shear angle.

2. The method of claim 1 , further comprising rotating the radiation source and the detector while the cellular panel is stationary to achieve the tilt angle.

3. The method of claim 1 , further comprising rotating the cellular panel while the radiation source and the detector are stationary to achieve the tilt angle.

4. The method of claim 1 , wherein the tilt angle is between an inclusive range of twenty degrees to fifty degrees (20°-50°).

5. The method of claim 1 , further comprising using X-ray radiation as the radiation.

6. The method of claim 1 , further comprising calculating the actual shear angle using the tilt angle and the projected shear angle.

7. The method of claim 1 , further comprising obtaining a first image of a first interior wall at a first location to determine a first actual shear angle, and obtaining a second image of a second interior wall at a second location to determine a second actual shear angle.

8. The method of claim 7 , further comprising averaging the first actual shear angle and the second actual shear angle to obtain an average shear angle for the cellular panel.

9. The method of claim 1 , further comprising identifying the projected shear angle between a line perpendicular to the facesheet and a line extending through node welds of the interior wall.

10. The method of claim 9 , further comprising a user of the imaging system determining the projected shear angle.

11. The method of claim 9 , further comprising the imaging system automatically determining the projected shear angle using boundary detection.

12. The method of claim 9 , further comprising placing a reference element on a surface of the facesheet to assist in identification of the line perpendicular to the facesheet.

13. An imaging system for determining an actual shear angle between an interior wall and a facesheet of a cellular panel, the imaging system comprising:
a radiation source;
a detector diametrically opposed to the radiation source and configured to detect radiation transmitted through the cellular panel from the radiation source; and
at least one computer processor in operative communication with the radiation source and the detector, the at least one computer processor configured to:
position the radiation source and the detector at a tilt angle relative to a line perpendicular to the facesheet of the cellular panel,
transmit radiation from the radiation source through the cellular panel to the detector to obtain an image of the interior wall of the cellular panel,
identify in the obtained image the line perpendicular to the facesheet,
identify in the obtained image a line parallel to the interior wall,
measure in the obtained image a projected shear angle between the line perpendicular to the facesheet and the line parallel to the interior wall,
determine an actual shear angle between the facesheet and the interior wall using the tilt angle and the projected shear angle, and
determine if the cellular panel is within predetermined specifications based on the determined actual shear angle.

14. The imaging system of claim 13 , wherein the cellular panel is positioned closer to the detector than the radiation source.

15. The imaging system of claim 13 , wherein the at least one computer processor is configured to use node welds of the interior wall in the obtained image to identify the line parallel to the interior wall.

16. The imaging system of claim 13 , wherein the at least one computer processor is configured to use a reference element attached to a surface of the facesheet in the obtained image to identify the line perpendicular to the facesheet.

17. An automated method for determining an actual shear angle between an interior wall and a facesheet of a cellular panel using an imaging system including a radiation source, a detector diametrically opposed to the radiation source, and at least one computer processor in operative communication with the radiation source and the detector, the automated method comprising:
moving the radiation source and the detector such that a line extending between the radiation source and the detector is at a tilt angle relative to a line perpendicular to the facesheet;
acquiring an image of the interior wall by transmitting radiation from the radiation source through the cellular panel to the detector;
identifying in the acquired image a projected shear angle between the line perpendicular to the facesheet and a line extending through node welds of the interior wall;
measuring the projected shear angle;
determining an actual shear angle between the facesheet and the interior wall based on the tilt angle and the measured projected shear angle, and
determining if the cellular panel is within predetermined specifications based on the determined actual shear angle.

18. The automated method of claim 17 , further comprising using the following equation to determine the actual shear angle:
tan θ=tan α*sin φ

where θ is the actual shear angle, α is the measured projected shear angle, and φ is the tilt angle.

19. The automated method of claim 17 , further comprising storing a value for the tilt angle between an inclusive range of twenty degrees to fifty degrees (20°-50°) in a memory associated with the at least one computer processor.

Assignees

• Boeing Co

Inventors

• Thompson Jeffrey G
• Nansen David S
• Bulthuis Ronald V
• Riechers Thomas E

Classifications

• B32B3/00

  Layered products comprising a layer with external or internal discontinuities or unevennesses, or a layer of non-planar shape; Layered products comprising a layer having particular features of form · CPC title

• G01N23/04 Primary

  and forming images of the material · CPC title

• G01B15/00 Primary

  Measuring arrangements characterised by the use of electromagnetic waves or particle radiation, e.g. by the use of microwaves, X-rays, gamma rays or electrons (characterised by the use of optical techniques G01B9/00, G01B11/00) · CPC title

• G01N1/00

  Sampling; Preparing specimens for investigation · CPC title

• G01N2223/615

  composite materials, multilayer laminates · CPC title