【作者】 施国凯；

【导师】 孙毅；

【作者基本信息】 浙江工业大学 ， 机械设计及理论， 2009， 硕士

【摘要】 可展桁架结构是近些年发展起来的一种新型折叠结构体系,在航空航天,机械工程和日常生活中都有广泛地应用。本文对可展桁架的结构设计和动力学分析进行了深入系统的研究。首先,结合车载式自动遮阳装置支撑结构的功能要求、应用环境需求分析结果以及现有可展桁架结构型式的特性对比,选定在剪式单元可展开折叠机构的运动机理上进行改进设计,并提出基本运动准则和约束条件,完成抛物面型和圆柱面型两种可展桁架的赋形设计,同时通过ADAMS仿真软件实现圆柱面可展桁架的运动仿真,验证几何设计和运动的可行性。按照本文的设计原理,可进一步实现可展桁架按任意曲线赋形,丰富了多连杆折叠机构的结构形式。其次,采用有限单元法建立圆柱面可展桁架展开状态下的有限元模型,并通过模态分析掌握了铰接杆、支撑轴截面尺寸变化和等效集中质量变化对结构整体模态和刚度的影响,同时结合可展桁架结构的实际应用环境完成强风载荷的分析。并以上述的分析结果为依据,选择铰接圆管外径和壁厚为优化设计参数,建立数学优化模型,再利用ANSYS软件进行圆柱面可展桁架的截面尺寸优化设计,以获得满足最佳设计要求的截面尺寸参数。然后,针对圆柱面可展桁架的结构特点,应用多刚体系统动力学理论的拉格朗日方法建立系统动力学方程,通过运动求解分析其动力特性,得出驱动力模式与桁架系统运动的关系,并通过ADAMS动力学分析软件验证上述方法的正确性。最后结合虚拟样机技术和有限元技术将可展桁架中的关键铰接杆柔性化,简单、方便地实现了刚柔耦合动力学仿真求解,分析柔性铰接杆对可展桁架运动的影响,避免了传统方式的繁琐推导和复杂计算。最后,基于上述工作的基础,本文完成了圆柱面可展桁架的1:1实物样机试制,并通过收合实验,验证赋形设计理论的正确性和运动的可行性。更多还原

【Abstract】 The deployable truss mechanism is a new type folding architecture developed in the recent several years. It’s widely used in a lot of fields, such as aerospace, mechanical engineering and daily life etc. Structural design and dynamic analysis have been studied systematically for deployable truss mechanism in this dissertation.Firstly, according to the functional requirements of supporting structure used in an automatic sun-shading device of automobile, such as demand analysis of application environment and characteristics contrast of the currently available deployable truss, the paper indicated a new design and moving norms and completed the improve design based on deployable scissor truss which realized the parabola and cylinder shaping of mechanism. And it simulated the motion of mechanism by the aid of ADAMS software which validated the feasibility of geometric design. Following the design principle in the thesis, it can be further realized to get an arbitrary curve shaping and enriched the forms of the multi-link folding structure.Secondly, it was established that the finite element model of the deployable cylinder truss structure while unfolding and researched on what affect the cross-section size changes of hinged rod and supporting axes and the equivalent lumped mass change have on the stiffness and model of the truss with the help of model analysis, simultaneously, it accomplished the strong wind load analysis under the environment of practical application. Eventually, according to the results of above analysis, it made the diameter and wall thickness of the hinged rod as the optimization design parameters and built up the mathematical optimization model, what’s more, with the help of ANSYS, it realized the optimization design of deployable cylinder truss and received the best design parametersThirdly, due to be dead against the structural characteristics of the deployable cylinder truss, the paper set up the dynamic equation of the model based on Lagrange equation in the multi-body system dynamic theory, by calculating equation and analyzing the dynamic characteristics, it obtained the relationship between the driving force and the movement of the truss system, further, the correctness of the above theory was verified through the application of ADAMS. At last, by combining of the virtual prototyping technology and finite element technique, the thesis successfully made the key rigid- rod as flexible and fulfilled the rigid-flexible coupling dynamic simulation simply and easily, which can analyze the impact of flexible rod during the movement, besides, that can avoid the tedious derivations and complex calculations in traditional methodFinally, based on the above research, the paper set up a physical prototype of deployable cylinder truss by 1:1 ratio and verifies the correctness of shaping design theory and feasibility of the movement through a lot of experiments.更多还原