Optimum Conversion of Design Optimized Fiber Paths to 3D Printable G-Codes

Topology and fiber path optimizations result in the ideal design of the shape and fiber placement, respectively, in composite structures subjected to certain loads and constraints. Advancements in additive manufacturing (AM) can enable such designs to be manufactured. Specifically, the use of continuous carbon fiber-reinforced plastics (CFRPs) in AM or automated fiber placement (AFP) allows for 3D printing of such topology and fiber path optimized designs. However, fiber path optimization methods generally result in a collection of fibers in loops (closed loops) that are impossible to print, and lines (open loops), which may be too short to print depending on the system. Additionally, placement of discontinuities, i.e., where a fiber path ends inside a part, can result in stress concentrations that degrade the part performance. This paper introduces an approach to automatically convert the collection of closed and open loops into printable set(s) of fibers. An additional optional consideration of stress concenterations can be provided to the algorithm, which is demonstrated using finite element analysis (FEA) for enhanced structural performance.