Remove Mesh Self-Intersections Based on Light Projection Algorithm

Offset in computer aided design and manufacturing (CAD/CAM) is a kind of important geometric operation, such as rapid prototyping technology, NC machining, the collision detection, etc. When offset distance d is greater than the minimum radius of curvature on the original surface, or part of the distance between parts of curved surface pieces, it causes self-intersection. Self-intersection makes distance between two models smaller than the offset distance r, leading to offset model local intersection or distortion. This paper proposes a method based on light projection algorithm to remove self-intersections and achieve good results. Firstly, set point coordinates on the original model as the light source locations and build the projection light according to adjacent plane vector weighted sum. Secondly, the projection light passes through the offset model. We extract the triangles on the outermost layer and load it into a list. Finally it is essential to filter the intersection points and construct triangle mesh. We use different discrete data models to do experiments and prove the validity and practicability of the algorithm.