Design on CAD system of airfield clearance zone
DONG Xiuping~1,HUANG Mingji~2,ZHANG Yuan~1(1. School of Mechanical Eng.,Beijing Univ. of Business & Tech.,Beijing 100048,China;2. School of Mechanical Eng.,Univ. of Sci. & Tech.,Beijing 100083,China)
As to the heavy tasks of airfield clearance zone design such as design,calculation,manual plotting and so on,the function frame of a special CAD system is proposed for airfield clearance zone design based on 3D terrain model and an integrated CAD system is developed by parametrization method. Some important functions of the special CAD system are implemented by the secondary development of AutoCAD using ARX(AutoCAD Runtime eXtension) and VC++. The establishment of data structure of 3D terrain triangle grids and modeling method of airfield clearance zone’s each limit surface are proposed. By construction,comparison and analysis on the 3D models of terrain and airfield clearance zone,the distribution of obstacles in airfield clearance zone can be displayed intuitively,and the ichnography and section graphs of airfield clearance zone including terrain graphs can be generated automatically. The application of an airport indicates that the special CAD system can simplify the heavy calculation and plotting tasks and has important significance to promoting airfield clearance design.