In this application video, a 8-cam (12 Mpx) MulticamDIC system was used to measure the deformation and
strain for a spherical membrane being inflated (in two steps) up until rupture.
The objective of the measurement was to determine the peak strain (of +2000 mstrain) before rupture occurred
and to model the shape of the membrane during inflation.
Using the MulticamDIC system, all cameras were operated, together live in Istra4D. Using one calibration target,
the projection was calibrated using the Clustered Bundle Adjustments Algorithm (CBAA), whereby any common
grid intersection point detected, by any number of cameras, contributes to the computation of one (system)
coordinate system. (No image stitching is used, meaning that no multiple projection calibrations were performed
of independent stereo rigs and later merged-together via fiducial references). In the correlation evaluation, the
facets/subset were aligned (parameterized) according to selected object shape model of a sphere, known as Object
Alignment Parameterization (OAP). This allows the measurement to be defined as to how the object topology
appears in shape, rather project an inaccurate planar model taken from selected reference camera.
During the startpoints search, the selected facet/subset can be seen in every camera. The section of the lowest
startpoint error is performed using the Multicamera Cluster Approach (MCA), meaning any combination of
cameras that yield the lowest residuum error that view the same facet, will contribute to the measurement.
In the graphical visualization, the 2D-overlay of the Eng. Principal Strain in mstrain and Total Displacement in
mm, can be seen. Measurement of +2250 mstrain are possible using the correlation algorithm of Istra4D V4.11.
A line gauge was also placed showing the temporal development of path length and engineering strain over
the line. Finally, a 3D-visualization model of the measurement can be seen.
RELATED SOLUTIONS
Subscribe to News
Get the Latest Information about:
| Products | Technologies |
| Applications | Special Offers |
