Adaptive Voxelization and Material-dependent Process Parameter Assignment for Multi-material Additive Manufacturing

Multi-material additive manufacturing (MMAM) offers a flexible way to produce complex and functionally graded materials (FGMs) with varying mechanical, electrical or chemical properties, leading to more sophisticated and cost-effective part designs and fabrications. However, the lack of material-aware printing capabilities in existing CAD and CAM software poses a significant challenge. MMAM with existing CAD/CAM software can only fabricate multi-material parts with sharp multi-material interfacial transitions. To address this challenge, we propose a novel adaptive voxelization and parameter assignment technique integrated with the commercial CAD software Rhinoceros 3D to achieve material-dependent variable printing toolpath generation. The proposed method enables adaptive process parameter assignment at variable resolutions. To meet the multi-material design specifications, the proposed method can generate G-code commands with adaptive process parameter assignment. The key novelty and contribution of this work is the mapping between the solid CAD design to the final printing toolpath with parametric transitions in the multi-material interfaces. Various transition functions, including radial distribution and linear transitions, can be defined to achieve graded material distributions. Graded voxel size is also achievable with finer resolution at multi-material interface regions to enable precise control of process parameters and material distributions, whilst coarse voxels are used for deposition in single-material regions. The proposed method sets the foundation for producing complex multi-material components by AM.