Non-developable Surface Mapping Method Of Approximate Expansion And Internal Structure

Integral panel is a flat part integrated with framework elements, connection elements and skin in traditional aircraft structure, it is the main supporting structure in aircraft, having the advantages of high-intensity, low-weight, and so on. The forming of complex integral panel requires meeting the need of aircraft gas figuration and fatigue-life, and the forming is very difficult. The primary problem in using the method of Numerical Control Manufacture-Shot Peen forming to manufacture the part on rough is to determine the size of the roughcast.According to the research on approximate development of small curvature aircraft panel surface in the period of designing the new generation of plane. On the assumption of ignoring the distortion of thickness, this paper determines the rough shape by the geometric modeling method of equal area developing using mixed mesh cell of triangle and quadrangle for the first time, presents the equal area developing arithmetic of quadrangle-triangle. On the virtual geometric symmetry axis, we puts forward the method of determining the developed coordinate of the point on the base band in the development of using regular quadrangle cell, determines the developed shape of internal structure in plane utilizing point-to-point mapping theory. Furthermore, We realize the approximate developing of undeveloped-irregular boundary surface using a few triangle cells.Applying the above-mentioned method, the author developed an approximate Developing-Mapping System based on CATIA V5 using VB, realized the development computing of panel surface and auto-drawing of developed shape in CATIA, dealt with the problem: getting mesh data from Analysis & Simulation module of CATIA, picking up structure information data in IGES, showing 2D developed model in CATIA.The applications on Chinese aircrafts showed the validity of the proposed numerical method in aircraft panel. We give out several typical instances in this paper, the result showed that the system has also wide application foreground in spaceflight, automobiles and ships fields.