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通过介绍以飞机为对象的集成制造系统 C I G M A,给出了一个实现计算机辅助设计技术集成的解决方案,如集成系统结构、数据管理模式等.与其它集成系统不同, C I G M A 系统不但具有数据统一、资源共享、易于信息交换、实时处理等特点,而且还具有测量造型的功能. C I G M A 测量造型子系统解决了飞机、汽车等行业普遍存在的无图纸实物的设计问题,具有自动化程度高、通用性强、易于修改、便于误差实时控制等特点,尤其是对于外形复杂、棱线较多的实物进行测量造型具有较好的效果. C I G M A 系统及其测量造型子系统已经应用于工业生产中,取得了显著的效益.“,”China needs to develop her own integrated manufacturing systems. We participated in the effort of developing such a system-CIGMA, which is an integration of CAD/CAE/CAM. Figure 1 shows the system structure of CIGMA. The system kernel lies in the center of CIGMA. Around the system kernel is the CAD module, which consists of the following subsystems: A) 3D geometry design ; B) feature based modelling; C) reverse engineering; D) solid modelling; E) advanced surface modelling; F) 2D drawing. We developed the reverse engineering subsystem, which is the main feature of CIGMA. Figure 4 gives the diagram of the reverse engineering subsystem. Different from others, we first divide the measurement data into several data blocks. After some pre processing of each data block, we fit each data block into a surface, then we join the surfaces into one surface. Our method gives better results when the objects have complex shapes and a lot of crest lines. CIGMA and its reverse engineering subsystem have met with preliminary success when applied in several Chinese factories.