Automatic Drapability Tester



The behavior of standard- and non-crimp fabrics
in forming and draping is of importance in any
production process of non-flat, fabric-reinforced
composite parts. As automation of such production
processes progresses, drapability and the detection
of defects during draping like gaps, loops, or
wrinkles become even more important.
DRAPETEST, a new automatic drapability tester,
allows to automatically characterize drapability and
the formation of defects during draping and forming.
The tester combines the measurement of the
force, which is required for forming, with an optical
analysis of small-scale defects such as gaps and
loops by means of image analysis. An optional
triangulation sensor can determine large-scale
defects such as wrinkles.
As a standardized simulation of the draping
process a flat circular sample of the fabric to be
tested is deformed at its center by means of a
motor-driven piston. A camera with an appropriate
illumination inspects the sample at several elevation
steps while the sample is rotated in order to
inspect a maximum percentage of its surface. In
the same manner the sample is scanned by the
optional triangulation sensor.




DRAPETEST is suited for fabrics made of glass,
Carbon, Aramid, and similar materials. It is based
on an earlier development by SAERTEX, a leading
producer of non-crimp fabrics, and proved its function
and the relevance of results in practice. Image
analysis technology developed at the Faserinstitut
Bremen (FIBRE) allows the automatic detection of