基于VR-CAD系统集成实现虚拟环境中建模

Immersive Modeling Based on Integration of Virtual Reality and CAD

传统计算机辅助设计工具受制于桌面系统非自然的人机界面,而虚拟现实技术(VR)以其沉浸感、交互感等特性为设计师提供了新一代更为自然的交互方式。但由于虚拟环境中缺乏有效的建模工具,产品开发过程中这项技术主要是作为可视化工具使用。作者提出了通过VR-CAD系统集成,利用传统CAD系统所提供的强大建模工具实现虚拟环境中的建模的解决方案。分别从横向集成和纵向集成两个角度出发,文中详细分析了虚拟现实系统和传统计算机辅助设计系统之间的不同连接方式,并基于3DMAX与CUBE采用两种方式进行了集成试验。其中一种是在面片层次上通过Unix和Windows间的Socket通讯将两个软件进行整合,另一种更通用的方法则基于VRML文件的共享。尽管集成系统所能处理的产品模型复杂度还受到一定限制,但初步的结果已经显示出该设想具有很大潜力。

Traditional CAD works suffer from unnatural human-machine interface supported by desktop system. With its character of immersion and interaction, virtual reality technique afford more natural interface of new generation to support designer. But owing to lack of modeling tools in virtual environment, the use of virtual reality technique is mostly limited to visualization in the product development process. This paper proposes a concept of immersive modeling based on system integration of virtual reality and CAD. Drawing on the study of different horizontal coupling and vertical coupling modes, two prototypes of integration are implemented between CUBE and 3DMAX. By one method, two systems are coupled in one process at the level of tessellation, which are transmitted through socket communicating between Unix and Windows platforms. The another more flexible approach is based on the VRMLfiles sharing. The resulting integrative VR-CAD systems can provide designers with an immersive environment, where they can use traditional CAD modeling tools to perform design works. Even though the complexity of the models that can be handled in real-time is limited in these two approaches, the prototypes demonstrate big potentials of the integrative concept.