Data Processing Method And Its Applications In Integral Impeller Reverse Engineering

With the continuous development of computer technology and automatic measurement technology, and the increasing market competition, the traditional design methods have been unable to meet the effectiveness requirements from product design and rigorous production. Reverse engineering has become an important technical means, playing an increasingly important role, in particular the digital manufacture of certain parts with complex characteristics. This technology has reached the various fields, including aerospace, medical, chemical, construction, and preservation of cultural relics, etc. The difficulty in reverse engineering is the huge number and disordered structure of the process, which also brings an enormous difficulty to the subsequent reconstruction of geometric model. Therefore, it is of great significance to improve the level of reverse engineering technology and study on how to start from the characteristics of point cloud data and realize the reconstruction of complex parts model of characteristics in high quality. This thesis is a study on the method and application of point cloud data processing, on basis of the typical complex parts of characteristics, namely the integral impeller reverse modeling process, and this thesis contains the following several aspects:At first makes an analysis on the surface geometry data measurement method, carries out a detailed comparison between the advantages and disadvantages of contact type and non-contact measuring method, selects an appropriate measuring equipment and develop a suitable data acquisition method of integral impeller blade surface, according to the material and structural characteristics of integral impeller, which is effective to solve the problems, such as the complex surface of the geometrical shape and interference on the surface.Section two elaborates several key techniques in point data processing stage. Through improving the “existing processing methods”, this section summarizes point data processing method, which overcomes the limitations of other methods, and is a more ideal method to meet the demands of subsequent model reconstruction of point data of integral impeller.Section three emphases on the implementation process of model reconstruction method and improve a method of curve and curved surface smoothing reconstruction, based on the theory of wavelet decomposition reconstruction and the pretreatment of point cloud data. On the foundation of rapid model reconstruction technology, this part completes the reconstruction of integral impeller model, combined with the processing of data files in the software.Section four explains several kinds of evaluation methods of reconstruction model in brief, mainly evaluates and analyses the evaluation and analyzes the precision and quality of reconstruction model, and proves that refactoring data model is within the reasonable error range, through the study on the control strategy of surface reconstruction strategy.At last, the point data of integral impeller was collected and pretreated several types, reversely reconstructs the 3-d model, and verifies the quality of the reconstructed surface model. Practice shows that it is a kind of impeller data processing and reconstructed method, which could improve the design efficiency, shorten product development cycle.