多面体装配模型复合配置空间递进式生成方法

发布时间：2018-05-07 22:42

本文选题：装配模型 + 变拓扑机构　；参考：《华中科技大学》2013年硕士论文

【摘要】：除了满足力学等性能，机械系统需要实现预定的功能，这些功能包括由系统运动实现的行为功能。然而，在系统设计阶段，一般的CAD模型能够直接反映系统的组成与结构，却不能直接表达系统模型在使用时的实际行为。对于复杂变拓扑机构模型，设计者自己也很难全面预测模型的真实行为，如不同目标位置间的可达性、运动不确定性等。所以，系统行为预测能帮助设计者及时发现并回避错误设计，优化系统运动路径等，从而成为正确实现模型预定功能及操作规划的重要保证，可广泛应用于运动行为检验、系统重构及各类工程设计中。对于机械装配模型行为的研究，首先提出了复合配置空间(Composite ConfigurationSpace, CCS)的概念表示机械装配系统行为。复合配置空间的两个基本要素是配置参数及参数定义域。在运动几何的基础上，文中以面面接触关系为依据严格定义了模型接触状态。接触状态反映模型所有零件间的接触关系，继而决定任意两零件间的相对运动关系，从而对系统运动进行参数化。系统行为分两个层次，即参数在参数域内的变化和参数域间的变换。两个层次的参数变化均能引起接触状态转换。当参数在参数域内变化时，系统参数处于同一个连续配置空间，，其中一个区域对应一个接触状态，接触状态的变化确定参数定义域边界。另外详细介绍了参数在参数域间变换时配置空间的映射变换关系以及复合配置空间的性质。然后，面对CCS的自动构建问题，提出一种多面体装配模型配置空间递进式生成方法。该方法对于多面体CAD装配模型中某特定面面接触状态，以一对接触零件作为初始子装配，以求解一个子装配加入一个零件后的新子装配的配置空间为循环体，逐次引入所有装配零件直至完成整体装配模型的配置空间求解。接着通过一定的人工交互进一步求解所有接触状态下CCS。最后，列举了若干实例详细说明了其装配模型CCS求解步骤，说明了研究成果的可行性、有效性及适用性。
[Abstract]:In addition to meeting mechanical properties, mechanical systems need to perform predefined functions, including behavioral functions implemented by system motion. However, in the stage of system design, the general CAD model can directly reflect the composition and structure of the system, but can not directly express the actual behavior of the system model in use. It is difficult for the designer himself to predict the real behavior of the complex variable topological mechanism model, such as the reachability between different target locations, the uncertainty of motion, and so on. Therefore, system behavior prediction can help designers find and avoid the wrong design in time, optimize the system motion path, and become an important guarantee to realize the model predefined function and operation planning correctly, and can be widely used in motion behavior testing. System reconfiguration and all kinds of engineering design. To study the behavior of mechanical assembly model, the concept of Composite configuration Space (CCS) is proposed to represent the behavior of mechanical assembly system. The two basic elements of compound configuration space are configuration parameters and parameter domain. On the basis of kinematic geometry, the contact state of the model is strictly defined based on the surface contact relationship. The contact state reflects the contact relationship between all parts of the model, and then determines the relative motion relationship between any two parts, thus parameterizing the system motion. The system behavior is divided into two levels: the change of parameters in parameter domain and the transformation of parameter domain. The change of parameters at both levels can lead to the transition of contact state. When the parameters change in the parameter domain, the system parameters are in the same continuous configuration space, where one region corresponds to a contact state, and the boundary of the parameter domain is determined by the change of the contact state. In addition, the mapping transformation relation of configuration space and the properties of compound configuration space are introduced in detail. Then, in the face of the problem of automatic construction of CCS, a progressive generation method of configuration space for polyhedron assembly model is proposed. For a particular surface contact state in a polyhedron CAD assembly model, a pair of contact parts is used as the initial sub-assembly, and the configuration space of the new sub-assembly after a sub-assembly is solved is a circular body. All the assembly parts are introduced one by one until the configuration space of the whole assembly model is solved. Then the CCSs in all contact states are solved by a certain amount of manual interaction. Finally, some examples are given to illustrate the steps of solving the assembly model CCS in detail, and the feasibility, validity and applicability of the research results are illustrated.
【学位授予单位】：华中科技大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：TG95;TH112

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