Study On Equipment Control, Process Optimization And Simulation For Rapid Prototyping

Equipment control is basal for successful implementation of the Rapid Prototyping (RP)manufacturing. Process optimization is crucial to the correct and efficient working of RP.Process simulation is an effective means of process validation and one of key technologies forVirtual Manufacturing. At present, the researches on these aspects are incomplete. So, thispaper focuses on these aspects and studies some key technologies. The main contents andresults are as follows:(1) A reconfigurable architecture of control software for RP equipment is introduced.Reconfigurable mechanism is established based on component technology. Reconfigurablemodules are divided according to the similar functions of control software. The key dataobjects of control software are defined. The reconfigurable modules are designed as COM(Component Object Model) component. A GUI (Graphic User Interface) for equipmentcontrol with multi-tasks and multi-parameters, is designed. By reconfigurable developing, thecontrol software is successfully applied to two different RP equipments.(2) An extendable architecture of tool path planning software for RP equipment isintroduced. Extendable mechanism is established based on plug-in technology. Extendablemodules are divided according to the data processing of tool path planning software. The keydata objects of tool path planning software are defined. The extendable modules are designedas plug-ins. A host program for tool path planning with multi-tasks and multi-parameters, isdeveloped. Parallel algorithm for path generation is studied and verified by experiment.(3) Computer-aided production efficiency optimization method for RP process is studied.After analysing the time consumption of RP production process,2.5-D nesting rules areestablished, aimed at arranging the3-D parts on the2-D platform more efficiently. Then,computer-aided2.5-D nesting is studied and a simplified method is presented. The methodcan transform the2.5-D nesting to2-D nesting by projection. At last, an experiment is givento verify the proposed optimization method.(4) Geometric simulation for RP process is studied. A common model, namely DiscretedBuilding Space Model, for showing the addition of material in RP process is presented.According to the corresponding roles of building vector in different RP processes, dynamicgeometry simulations of “adding” RP process and “cutting” RP process are studied based onthe model. In order to reduce the graphics processing data, dynamic reduction algorithm fordisplay data is studied. At last, several common models are used to verify the proposedalgorithm. (5) Bas-relief image processing methods for RP equipment is studied. The Visual Toolkit(VTK) is used for generating the3-D model from2-D bas-relief image and extracting thecontours from3-D bas-relief model. Then, the NC code generation for bas-relief is studiedbased on the extendable architecture of tool path planning software. Due to the advantages ofRP process and the characteristic of bas-relief, hollow bas-relief is presented to reduce thematerial used in RP process. The method for directly generating NC code for hollow bas-reliefis studied. At last, a hollow bas-relief is fabricated by Selective Laser Melting (SLM) process.(6). Computer-aided fabrication quality optimization method for SLM process is studied.A two-step method is proposed for optimizing building orientation and energy input. Anoptimization model for building orientation is established and a solving method based ongenetic algorithms is given. In order to optimize energy input, a static lookup table isestablished. At last, an experiment is carried out to verify the proposed optimization method.