  Automatic draping of carbon-fiber prepreg plies for the aerospace industry is
a promising technique for lowering the manufacturing costs and to this end, a
thorough in-process quality control is crucial. In this paper, out-of-plane
defects in the layup are investigated. After draping, air pockets are
occasionally encountered. The question is, if such apparent defects can be
mitigated sufficiently during vacuum debulking. The 3D topology is measured by
means of a structured-light 3D scanner and air pockets are segmented. An
approximate mass-spring ply model is used to study the behavior of the air
pockets during application of vacuum pressure. The model is computationally
fast and will indicate online whether the air pocket will be removed or manual
intervention is required. Upon comparing the model predictions with
experimental data, it is shown that the system is capable of correctly
predicting 13 out of 14 air pockets in a test layup.
