Understanding the response of composite materials subject to dynamic loading conditions is necessary for their safe and efficient application to many of the world's engineering problems where strength-to-weight ratios are vitally important. To examine the response of composite materials subject to dynamic out-of-plane impacts, an optical technique known as fringe projection was used to measure the resulting out-of-plane displacement from drop weight impact tower testing and horizontal impact testing using a gas accelerated projectile. The velocity histories as well as the strain rates can be identified through consideration of the measured displacement histories. The associated acceleration histories, force histories, and impact based bending stiffness can also be calculated, but achieving consistent and logical results for those parameters demonstrated a greater dependence on data resolution. To ensure test results gained from small specimens can be applied to large ones, consideration of potential size effects is required. Scaling factors of three, five and ten were used to scale composite materials subject to horizontal impact from scaled gas accelerated projectiles. The whole-field out-of-plane displacement histories of the non-impact surface of the test specimens were captured using fringe projection. Through consideration of the displacement histories at the point of impact on the non-impact surface, readjusted for scale, a size effect was not observed for displacement within the elastic region. Scaling was unable to account for the damage modes in test specimens across scales. The damage modes present and the delamination area in the test specimens were more advanced in larger specimens.
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