Imaging and analyzing crack propagation in glass
AssigneeCorning Incorporated
InventorDavide Giassi
Life of this patent
Estimating the term…
Abstract
An imaging system for acquiring time-resolved images of crack propagation in glass samples includes a light source and data camera in a shadowgraph detector configuration, and a trigger camera to acquire images over an appropriate time window to capture crack propagation. Suitable software-based processing and analysis methods facilitate identifying individual cracks, branchpoints, and fragments in the images, as well as measuring their individual and statistical properties.
Claims29
An imaging system comprising:
- a support for placement of a glass sample thereon;
- a light source configured to illuminate the glass sample;
- a crack initiator mechanism comprising a movable pin configured to be substantially perpendicular to the glass sample upon impact;
- a triggering camera configured to generate, responsive to detection of a crack in the glass sample, a trigger signal;
- and
- a high-speed data camera to capture light transmitted through the illuminated glass sample in a shadowgraph configuration, the high-speed data camera comprising memory configured as a circular buffer that ceases to overwrite frames responsive to the trigger signal.
A method comprising:
- placing a glass sample on a support;
- illuminating the glass sample;
- capturing shadowgraph images of the glass sample with a high-speed data camera configured to cyclically store the captured images in a circular buffer;
- initiating a crack in the glass sample;
- and
- detecting the crack in the glass sample with a trigger camera configured to generate a trigger signal responsive to detection of the crack,
- wherein the trigger signal causes the data camera to cease overwriting frames in the circular buffer.
A computer-implemented method of analyzing one or more digital shadowgraph images of a crack structure in a glass sample, the method comprising:
- converting the one or more digital shadowgraph images into a binary crack structure image;
- creating a skeleton structure from the binary crack structure image;
- identifying one or more gaps in the binary crack structure image based on the skeleton structure;
- and
- closing the identified one or more gaps in the binary crack structure image.
A computer-implemented method of analyzing a time-resolved sequence of digital shadowgraph images comprising shadowgraph images of a crack propagating in a glass sample, the method comprising:
- processing each of the shadowgraph images of the crack propagating in the glass sample by:
- converting the shadowgraph image into a binary crack structure image,
- creating a skeleton structure from the binary crack structure image, and
- identifying crack extremities in the skeleton structure;
- and
- storing coordinates of the identified crack extremities as a function of time.
Dependencies are inferred from the claim text.