Study On The Part Accuracy Of Rapid Prototyping System Based On Reverse Engineering

Reverse Engineering (RE) which stems from precision measurement and quality inspection is a technology that serves to transfer from design lower reaches to design higher reaches. In this paper, a preliminary discussion is presented on the application and appraisal of RE in Rapid Prototyping system on the basis of a self-designed reverse model building system.In order to produce more complex parts by Rapid Prototyping, a new concept-sub dividing part is introduced in Rapid Prototyping. The method renders the whole mould unloading process into a several parts unloading process. Through sub dividing part proper designed, some local parts are protected in mould unloading and the complex parts are produced successfully in Rapid Prototyping.Under a serious analysis of current commercial profile machine, a three-coordinate reverse model building machine is put forward according to the experimental requirement. This system includes X-Y-Z three axle gear system, laser measuring system, data acquisition and processing system. The design and operation principle of every section is analyzed in details and every system is assembled completely. It successfully completed the three-coordinate data acquisition of common model.A new reverse model building software system is developed based on the three-coordinate reverse model building machine. The software system includes four parts: kinetic control, data acquisition, data processing, and model building. The idea of design and function of every part are analyzed. The software system fulfills the kinetic control of reverse model building machine and model drawing of acquired data successfully. Two methods are adapted in the assess of model building part, which are dummy appraisal method and real appraisal method respectively.In application, with dummy appraisal method, appraisal of Rapid Prototyping parts is obtained though the contrast simulating model with the original part overlap, color and surface areas discrepancies. Some work pieces are constructed by reverse data cloud building method. A new data processing path is proposed in this reverse data cloud building method. This new data processing path fulfills building model of mouse, bevel gear and impeller part successfully. Finally, an appraisal for the precision of rapid prototyping work pieces is obtained through the comparison the reverse model and the original one.