Topology Optimization for Design of Highly Tailored Composites for AFP Manufacturing

With the advent of automated tow placement and additive manufacturing, a designer of composite structures must deal with not only an enormous design space, but also perform a highly complex and computationally expensive analysis to determine what is a ldquo;goodrdquo; design and to simulate the structural behavior. nbsp;In the isotropic world of metals, there has independently been a tremendous amount of research (and success) in the development of topology optimization tools that develop design concepts that are not always obvious a priori, but that offer significant performance advantages and (with additive manufacturing) are often cheap and easy to produce. nbsp;Topology optimization algorithms use a fictitious density in each finite element as a design variable, and usually optimize this ldquo;densityrdquo; to find the best places to leave material in place (density 100%), and the best places to remove it (density 0%). nbsp;This problem has some fundamental similarities to the design of a composite part with AFP ndash; since AFP is essentially an additive manufacturing process, we have tight control of where to add material (and where not to) for a given ply. nbsp;Our innovation extends the topology optimization approach to apply to optimum design of manufacturable AFP structures. nbsp;The objective of the proposed design tool will be to optimize the tow steered laminate fiber path directly for a representative composite curved panel. As an example, a cylindrical panel with a cutout, and subjected to complex pressure and in-plane loads will be considered. nbsp;The tool will be integrated with Siemens NX/NASTRAN, and eventually may be integrated into tools such as Simcenter3D and Fibersim.