【作者】 郭兴辉；

【导师】 秦伟；

【作者基本信息】 重庆大学 ， 机械设计及理论， 2008， 硕士

【摘要】 为适应复杂、恶劣工作环境的变化或多功能要求的变化,现代机械系统要求现代机构向自重构性发展,即机构在运动过程中,可以改变其拓扑结构、运动学参数或动力学参数。变拓扑机构是在变胞机构的基础上提出的一类具有自重构性的新机构,变拓扑机构可以通过构件的缩并与裂变、邻接关系的变化和运动副类型的变化,以改变机构在运动过程中的构型,适应不同的工作环境,拓展了机构应用的范围。目前,变拓扑机构在构型的综合与选择、构型间的关系、运动学和动力学分析等领域还有大量的问题没有解决。由于对变拓扑机构的分析涉及到多种构型分析,具有复杂性,因此寻找多种构型之间的拓扑结构变换关系就显得非常重要,同时变拓扑机构的变换点的选择以及对前后构型的影响也是机构分析的重点。针对以上情况,本文进行了以下研究:①提出了变拓扑机构构型综合的方法,对三种变拓扑方式下机构构型综合的规律进行了研究,得到了一种变拓朴机构构型综合的实用方法。②通过对机构变换过程中前后构型之间关系的分析,建立了以瞬时功率差的平方最小为目标来选择机构变拓扑点的目标函数以及变换时的约束条件;通过分析机构两种构型间的关系,推导了机构速度矩阵在前后构型中的传递关系,为机构的奇异性分析提供了一种简便快捷的方法。③利用MATLAB软件对5-4杆变拓扑机构进行了仿真分析,得到了5-4杆机构第一次出现奇异位形时的机构的最优变拓扑点,通过对变拓扑机构进行运动仿真,得到了其运动曲线,在此基础上提出了变拓扑区域选择的方法。本文提出了的变拓扑机构的构型综合方法,分析了变拓扑点的选择和机构奇异位形计算中前后构型间的速度传递矩阵R;通过R阵的计算,简化了后一构型速度矩阵的计算步骤,充实了变拓扑机构的分析和设计方法。本文的研究工作对于变拓扑机构的设计及应用提供了比较重要的参考。更多还原

【Abstract】 In order to adapt to the exploration and poor working environment or multi-functional requirements, the modern mechanical systems require the modern machine develops towards the reconstruction. That is to say, machine can change its topology configuration, kinematic parameters or dynamics parameters in the process of movement. Variable topology mechanism which is based on the metamorphic mechanism is a new type of machine of self-reconstruction. By the combination and split of the bar, the change of connecting relationship and changing the type of kinematic pair , variable topology mechanism can change the machine configuration in the process of the working motion to be adapted to different working environment and expand the scope of application of the mechiansms.At present, variable topology mechanism hasn’t yet solved some problems such as the synthesis and the selection of the configuration, the relationship between the before and after configuration and the anslysis of kinematics and dynamics. It’s a very complex problem to analyse variable topology mechanism which involves in the variety of configurations. Therefore it is important to search the topology configurations transform relationships among the different configurations. And the selection of the topology transform point and the effect on the before and after configuration is the focus of the analysis of variable topology mechanism.To the above situations, this paper has carried on the following research:①The synthesis approach of variable topology mechanism configuration has been proposed.And the law of mechanism configuration synthesis under the three variable topology ways has been studied. Consequently, a method of the variable topology mechanism configuration synthesis has been obtained.②By the analysis of the relationship between the before and after configuration in the process of mechanism transformation, objective function of the variable topology point of the mechanism chosen according to an objective whose square instantaneous power difference is minimum and constraint condition have been built. By analyzing the relationship between the two configuration, its transmission relationship of the machine speed matrix has been obtained, which provides a convenient method for the analysis of the singularity of mechanism.③By using MATLAB software, the simulative analysis of five-four bar variable topology mechanism, has been carried on. Then the optimum variable topology point appears for the first time. Through the analysis of variable topology mechanisms, the mechanical motion curve has been obtained, Besides the method of selecting the variable topology region is proposed on the basis of the curve has been porposed.This paper has proposed the metheods of configuration of variable topology mechanism, and analysed the choice of variable topology points and calculation of the mechanism singularity between the before and after configuration of the speed of the transfer matrix R . Through the matrix R, it has simplified the calculation speed matrix steps of the after configuration and enriched the variable topology mechanism analysis and design methods. The research has offered important reference for the design and applocation of variable topology mechanism.更多还原