Differentiable Channel Design for Enhancing Manufacturability of Enclosed Cavities

Hollowing is a simple and effective method for achieving light-weighting by removing interior volume while maintaining the external shape of the model. However, the enclosed cavities created through hollowing can limit its applications due to the residual material restrictions of common additive manufacturing technologies, such as selective Laser Sintering (SLS) and Stereo Lithography Apparatus (SLA). To address this problem, we propose an efficient channel design framework to eliminate enclosed cavities and make the structures apply to common additive manufacturing technologies. The channels are treated as ideal objects with length and inclination angle. A differentiable channel planning is then devised to connect all enclosed cavities and make them manufacturable. An automatic optimization utilizing gradient-based optimization is applied to solve the problem, optimizing both the angles and positions of the channels to ensure the residual material can be discharged freely through the channels. Experiments and 3D printed models are carried out to demonstrate the effectiveness and feasibility of the proposed method.