Automated Handling of Composite Prepregs

Abstract

In the manufacture of composite components prepregs are stacked one layer at a time to make up the required structure. Dedicated tape laying machines are produced on industrial scales within the aerospace industry for simple shape, but large prepregs. The handling and lay-up operation of discrete, and complex shape prepregs on flat, single-curvature or double curvature surfaces has not been achieved mainly due to the limitation in automatic handling and robotics technologies. The main handling problems arise from three characteristics of the prepreg composite material; it is tacky to the touch, it is non-rigid and it has a backing sheet which protects the prepreg while it is handled but which must be removed after each composite profile has been layed up. A number of possible mechanisms for the backing removal have been investigated including the use of adhesives, vacuum devices, piercing the backing with a sharp instrument, and leaving tags of material on the edges of the composite profiles. A new design is proposed for handling the profiles by gripping the tags.