Concurrent print orientation and topology optimization for fiber reinforced additive manufacturing considering mass minimization and compliance minimization problems statements

Fiber reinforced additive manufacturing (FRAM) combines the benefits of composite materials and additive manufacturing to create components which are made of high-performance materials, have complex geometry, and are highly configurable to address a design objective. As such, FRAM components are perfect candidates for numerical optimization methods including fiber orientation optimization and topology optimization. Many methods optimize fiber orientation and topology parallel to the print plane and limit the available design freedom by constraining the solutions to exist only within a user-defined print-plane(s). This work proposes a numerical optimization method for FRAM which concurrently optimizes 3D print orientation (θ1,θ2,θ3)$$(\theta_{1} ,\theta_{2} ,\theta_{3} )$$, and component topology, (ρ). Print orientation design variables establish a domain-level, 3D orientation of FRAM print-plane and fiber orientation. The print orientation represents a diverse configuration of anisotropic material properties which improves a structural objective function. Optimized anisotropic material properties are unique to component loading, geometry, and problem statement. Topology optimization alters material distribution within an anisotropic state to improve the common objective function and allows integration of mass minimization problem statements. The method is applied to complex, industry-level examples and is used to solve compliance minimization and mass minimization problem statements. Optimized designs are compared to equivalent-mass metallic and conventional FRAM designs. Structural compliance of an aircraft seat component is improved by 38.4% compared to an equal-mass aluminum design. The mass of a mounting bracket is reduced by 51% compared to an equal-displacement aluminum design.