Vehicle Body Retrofit Design And Optimization Based On Reverse Engineering

Focusing on the retrofit design and optimization of vehicle body, which is based on reverse engineering, the three supporting techniques of reverse engineering are investigated in the present paper: the digitalization of complex curved surface, pre-processing of point cloud data, and modeling of complex curved surface and the extraction of feature surface. Based on the research above, the retrofit design and optimization of vehicle body are accomplished, and its products have got excellent market feedback.Aiming at the digitalization of complex curved surface, the importance of digitalized measurement technique to vehicle body reverse engineering is analyzed, and its fundamental theory, typical equipment and technical features are detailed. The plan principles and contents of body measurement paths are focused in the present paper. With the goal of supporting retrofit design of certain heavy truck's driver's compartment, the lectotype of measurement equipment, preparation of the pre-stage of measurement, plan of measurement paths and the measurement of the driver's compartment are accomplished.Aiming at improving the feasibility and completeness of point cloud data, its pre-processing techniques are discussed. Gouped by scanning beam point cloud and discrete point cloud, data sequencing is investigated, the automatic filtering and interactive filtering techniques are explained, second sampling and grid method for simplifying data are researched. The above research has been explained and approved in application.In the research of techniques in curved surface reconstruction and feature extraction, the modeling of NURBS interplation curved surface based on rectangular is focused, in which centripetal parameter is applied to construct node vector, the application of interplation method guarantees the accuracy of curved surface construction, bicubic NURBS curved surface is taken as an example to demonstrate the process of curved surface modeling, and the effectiveness of NURBS is approved in application; Meanwhile, the application of feature techniques in reverse engineering is also diSCUSSed, the recognition and extraction method of feature curved surface are investigated, the relationship between feature recognition and the curvature of curved surface is discussed, with the application of linear and non-linear least squares procedure, data fitting of conicoid in ball surface, cylinder surface and cone surface is...