基于物理模型的虚拟装配技术研究

虚拟装配是虚拟现实技术在产品设计领域的一个重要应用 .为了从运动学与动力学的角度来考察虚拟装配过程中零件的运动 ,以便更真实地反映虚拟环境中零件装配运动的本质规律 ,提出了一种虚拟装配环境中用于将装配几何约束自动映射为运动副约束的基于运动自由度分析的物理约束生成方法 ,同时 ,提出了基于变刚度弹簧模型的装配力交互输入方法 ,并实现了位移输入与装配力输入的映射 .另外 ,还给出了基于物理模型的虚拟装配的基本过程 .该方法在虚拟设计与装配原型系统的研究与开发中已得到实现 .

Research on Virtual Assembly Based on Physically Modeling

Virtual assembly is one of the most important applications of virtual reality in product design fields. Virtual assembly method based on physically modeling is proposed for further investigating the kinematics and dynamics performance of assembling parts during virtual assembly process in this paper. The automatic constraints mapping method, which maps geometrical constraints implied in assembly relationships onto joint relationships based on degree of freedom analysis, is presented to construct the physical constraint models for physically simulation in virtual assembly environment. A variable stiffness spring model, which maps the geometrical displacement onto assembly force, is devised to realize the interactive input of assembly force. The methods are implemented in the development of VIRDAS (Virtual Reality Design and Assembly System) and the primary process of virtual assembly based on physically modeling in VIRDAS is also given in this paper.