Automated Planning for Material Shaping Operations in Additive/Subtractive Solid Freeform Fabrication

Combining the advantages of layered manufacturing and material removal processes, additive/subtractive solid freeform fabrication (A/S SFF) can build parts with complex shapes without compromising precision requirements. However, preparing material removal operations requires special expertise, which has in fact become one of the bottlenecks of the A/S SFF manufacturing process. To achieve automated planning, a shaping process planner is being developed based on 3D solid representation and a surface classification scheme. This planner can generate numeric control (NC) codes for CNC milling in an automatic fashion on non-undercut features of arbitrary 3D input geometry. Planning approaches are also presented in order to shape parts accurately and efficiently. The proposed shaping planner thus delivers on the promise of fully automated process planning in A/S SFF.