Ballistic Impact Dynamic Modeling of Fabric for New Protection Systems

Fabric based protection systems are critical to many kinds of safety systems. A challenge as designs are attempted is that details of failure are not well understood and are difficult to model. For projectiles, failure is dependent on many parameters ranging from the size and shape of the impact point to the velocity of impact, and the conditions of the fabric in terms of weave, support, pre-tensioning and environment. For the designer trying to reliably handle a threat, this uncertainty cannot be resolved without significant testing. We will use a multi-scale approach to develop techniques to improve the fidelity of ballistics models for fabrics. Adaptive modeling techniques permit the resolution of necessary detail in failure regions so that reliable predictions can be. Designers have a variety of fabrics to choose from, including yarn impregnation techniques such as a shear thickening fluid. This research effort emphasizes effects of weaves as well as attempts to characterize in more detail how the shear thickening fluid effects the individual yarns and relates to ballistic performance. The end result will be a tool that designers can use to make decisions in the early stages of design using fabrics for safety systems.