Optical measurement device for inspection of discontinuities in aerostructures

A device for calculating a surface discontinuity of a structure, said structure having an outer surface and a thickness, said surface discontinuity extending from said outer surface into said thickness of said structure or above said outer surface, the device comprising:

• a plurality of spaced-apart light sources for illuminating said surface discontinuity, each of said plurality of light sources providing illumination toward said surface from a different angle;
• a digital camera for capturing a plurality of images of said surface discontinuity illuminated by the plurality of light sources;
• a processing component for receiving said captured images from said digital camera and calculating a true size of said surface discontinuity using said captured images;
• and
• a display operatively connected to said processing component for receiving and displaying said calculated true size of said surface discontinuity, wherein the plurality of spaced-apart light sources are configured to generate a plurality of distinct shadow and highlight patterns across the surface discontinuity from the different angles;
• wherein the digital camera is configured to capture images of the visible light reflected from the illuminated surface discontinuity, said images capturing the plurality of distinct shadow and highlight patterns;
• and wherein the processing component is configured to calculate the true size by generating a three-dimensional surface topography of the discontinuity based on an analysis of variations in the captured shadow and highlight patterns.

A method for calculating a surface discontinuity of a structure, said structure having an outer surface and a thickness, said surface discontinuity extending from said outer surface into said thickness of said structure or above said outer surface, the method comprising:

• providing a plurality of spaced-apart light sources;
• illuminating said surface discontinuity from different angles from said plurality of spaced-apart light sources;
• providing a digital camera;
• capturing a plurality of images of said surface discontinuity using said digital camera, said surface discontinuity being illuminated by at least one of said plurality of light sources;
• transferring said plurality of captured images to a processing component;
• calculating geometry data of said surface discontinuity calculated from said captured images, wherein said geometry data includes a true size of said surface discontinuity;
• and
• displaying said calculated data on a display, wherein the step of illuminating said surface discontinuity comprises generating a plurality of distinct shadow and highlight patterns across the surface discontinuity from the different angles;
• wherein the step of capturing a plurality of images comprises capturing images of the visible light reflected from the illuminated surface discontinuity, said images capturing the plurality of distinct shadow and highlight patterns;
• and wherein the step of calculating geometry data comprises generating a three-dimensional surface topography of the discontinuity based on an analysis of variations in the captured shadow and highlight patterns.