A skeletal line-based printing path planning method for continuous fiber reinforced composite structures

Continuous fiber-reinforced composite (CFRC) 3D printing integrates the benefits of additive manufacturing and advanced composites, enabling the fabrication of complex geometries with enhanced mechanical performance. However, CFRC printing faces significant path planning challenges. Conventional path generation methods frequently introduce printing defects such as voids and fiber misalignment, which substantially compromise the structural integrity of printed components. This paper proposes a novel skeletal line-based continuous path planning methodology that optimizes both manufacturability and mechanical strength, which is especially suitable for beam-like structures. The approach begins with extraction of the part's medial axis skeleton, followed by strategic decomposition into simplified sub-curves through skeleton node disconnection. Each sub-curve undergoes offset-based sub-path planning, after which the generated sub-paths are intelligently reconnected to form continuous loops. The process culminates in global path continuity through systematic loop interconnection. Experimental validation was performed to evaluate the efficacy of the proposed methodology. Comparative analysis demonstrates that our approach significantly reduces printing-induced defects while improving mechanical performance relative to conventional path planning techniques, including the Connected Fermat Spiral (CFS) method.