OpenGL based visual modeling for luffing mechanism of portal crane

In order to realize the rapid visual modeling luffer mechanism of portal crane, a special visual modeling platform based on OpenGL and C mixed programming in the Windows XP operation system for four-bar linkage structure was developed in this paper. Firstly, use the beam element to simplify the four-bar linkage structure, in which the driving parameters of the model were analyzed, and combining the model geometry size its spatial position parameters was estimated. Then applying the object-oriented programming, the four-bar linkage structure was represented by the relevant class and construct the model data structure according to NX Nanstran finite element preprocessing data format standard. Finally, establishment of OpenGL visual platform was described, and the drawing method of the model based on units was given, which could make the description of units be directly reflected by the visual model entity. The practice proved this platform could greatly improve the luffer mechanism of portal crane modeling speed and has visual and precise advantages.