3D Model Based Machining Process Planning

The wide application on fields of designing and NC programming based on 3D model of part not only provide the supporting for applying 3D based process planning, but also raise the challenge for the design capability of 3D based process planning. The 3D based process is not just replacing 3D process drawing with 3D model, it is concerned with schemas of designing, managing information applying of process. This paper presents a novel architecture of modeling process information in 3D scene, the 3D based architecture proposed manages process information on the base of geometries and serial changes, which reflect machining operations applied to part, of geometry of part from raw material to final part and comprises such three sub-modules as manufacturing features, 3D model based processes and manufacturing resources. A methodology is exploited aiming at reducing overload of 3D modeling for process planner and keeping the consistency among 3D working procedure models when inevitable process change occurred, then a related algorithm is detailed in which the process decision information retrieved from the technician is transformed automatically to geometrical information to generate 3D working procedure model. Several typical applying of 3D based process consisting of Recognition and analysis of technology dimension chain based on 3D serial model, NC programming for CMM and analysis of feasibility of process are discussed and a prototype is demonstrated to verifying validity of the architecture and the methodology.