Continuous tow shearing for manufacturing variable angle tow composites

Automated fibre placement (AFP) is the key technology for manufacturing variable angle tow (VAT) composites with tailored fibre paths. Although it was developed in the 1980s, much research still focuses on the minimization of the process-induced defects because the fundamental principle has not been changed. In this work, a novel fibre placement technique using the shear deformation characteristic of dry tow has been developed, which was named ‘Continuous Tow Shearing (CTS)’. Through the prototype tests, it is shown that CTS could significantly reduce process-induced defects such as fibre wrinkling, resin rich areas and fibre discontinuity. Also, an intuitive notation for defining a curved tow path using piecewise quadratic Bezier curve is developed.