参考价值.
关键词:机场; 净空区; 三维地形; CAD
中图分类号:TU248.6; TP391.72
文献标志码:A
Design on CAD system of airfield clearance zone
DONG Xiuping1, HUANG Mingji2, ZHANG Yuan1
(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)
Abstract: 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.
Key words: airfield; clearance zone; 3D terrain; CAD
0 引 言
机场净空区是为保证飞机起飞、着陆和复飞的安全性,在机场周围划定的限制地貌、地物高度的空间区域[1-2],其好坏直接关系到飞行安全.为保护机场净空,国务院于2001年颁布新的《军用机场净空规定》,提出净空区各处地形地物的许可高度,即现行机场净空规格.新规定的机场净空区由升降带、端净空区和侧净空区等3部分组成(见图1),其范围和规格根据机场等级确定.
