Apparatus, method and article for direct slicing of step based nurbs models for solid freeform fabrication

摘要: Direct slicing of CAD models to generate process planning instructions for solid freeform fabrication may overcome inherent disadvantages using STL format in terms the accuracy, ease file management, and incorporation multiple materials. This paper will present results our development a direct algorithm layered fabrication. The was based on neutral, international standard (ISO 10303) STEP-formatted NURBS geometric representation is intended be independent any commercial software. following aspects effort presented: 1) Determination optimal build direction upon STEP-based models; 2) Adaptive subdivision data refinement; 3) Ray-casting slice generation into sets raster patterns. Feasibility studies applying example involving multi-material structures also presented.