Improvement in automated ply cutting and handling

Design technologies limited's ultrasonic cutting process has the unique benefit of cutting through the prepreg leaving the protective backing layer intact. A family of needle based grippers has been developed and patented by the National Engineering Laboratory. These grippers are able to pick up the cut prepreg off the uncut backing layer and automatically transfer them to a tool at the side of the machine. To apply the two proceses tin practice necssitates two gantries, one carrying the ultrasonic head with the other an assembled matrix of gripper devices. This matrix has to be programmable to accommodate a reasonable range of ply sizes. Up to nine grippers have been used and a good accuracy of positioning is assured by the use of a clamping bar which is positioned at the center of the component. The benefits of this development are a significant reduction in labor and an increase in productivity of the cutter is the removal of plies in most cases happens in parallel with the ultrasonic cutting.