The Impeller Modeling And CAM Research Based On Reverse Engineering

Reverse engineering is based on products or models which is already existing,through the three-dimensional measuring equipment to obtain the surface point cloud data,,according to the obtained 3D CAD model of point cloud fitting after treatment, then used to the product analysis, manufacturing and innovation. In this paper, based on the reverse engineering design. Studied the denoising technique in the process of the impeller reverse. Put forward curved surface fitting for processing and verified tool selection and path generation the NC machining.Point cloud data preprocessing is an important technique in reverse engineering. The quality of pretreatment process of point cloud denoising will have a direct influence on the subsequent surface modeling. In this paper describes the technical process of point cloud data preprocessing, compared methods of the denoising and smoothing, improved the data processing algorithm. According to the characteristics of research object, proposed piecewise denoising fairing method to the point cloud, The big noise and redundant data point cloud removal first, then the corresponding streamline, Then we use improved piecewise curvature examination method of the processing. Use the local corner point cloud smoothing method to smooth the point cloud, avoid damage the feature of point cloud in the global fairing. Get the satisfactory point cloud processing effect.CAD model reconstruction surface is one of the key research of reverse engineering, and the NC machining is carried out on the basis of 3D model, which are closely linked to the each other. In the current process of reconstruction surface in reverse engineering, not considering the contact and influence with the machining process. It appears the machining accuracy is not up to the fitting accuracy, a series of problems such as over cutting and interference in NC machining. In this study, introduces the principle and method of surface reconstruction, finished the impeller reverse modeling. Analysis of the surface form and fitting method to the surface reconstruction process and the Influence to NC machining, Put out the method of curved surface fitting method based on numerical control machining, The model get by this methods not only meets the requirement of the obtained model reconstruction in reverse engineering accuracy, but also guarantees the smooth progress of the NC machining. Finally, validated in NC machining of the obtained model. Explored the NC tool selection and tool path trajectory generation method. Trajectory generation simulation of NC machining, Get the trajectory simulation tool path of rough machining and finish machining.