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 âgoodâ design and to simulate the structural behavior. 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. Topology optimization algorithms use a fictitious density in each finite element as a design variable, and usually optimize this âdensityâ to find the best places to leave material in place (density 100%), and the best places to remove it (density 0%). This problem has some fundamental similarities to the design of a composite part with AFP â 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. Our innovation extends the topology optimization approach to apply to optimum design of manufacturable AFP structures. 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. The tool will be integrated with Siemens NX/NASTRAN, and eventually may be integrated into tools such as Simcenter3D and Fibersim. Potential NASA Applications (Limit 1500 characters, approximately 150 words): Highly tailored composite structures for any vehicle. Spacecraft structures with stringent strength, stiffness, and stability requirements Aircraft structure (wing skins, control surfaces, pressure vessels) Launch vehicle structures Science payload structures Potential Non-NASA Applications (Limit 1500 characters, approximately 150 words): Commercial and military aircraft applications High performance ground vehicles (e.g. racing) Unmanned aircraft Commercial spacecraft and launch vehicles Dur
