【作者】 胡其彪；

【导师】 关富玲；

【作者基本信息】 浙江大学 ， 结构工程， 2001， 博士

【摘要】 空间可伸展结构是近四十年迅速发展起来的新结构，无论在空间站还是在通讯卫星上都得到了广泛的应用。新的空间技术要求无线大口径化、轻量化、高精度、高收纳率和高展开可靠度等，本文对其在构筑思想、设计实践、展开运动力学及可伸展结构特有的结构力学问题几方面展开系统的研究。 本文对可伸展结构进行了分类，并以分类为基础，提出了概念设计的四个层面思想，在不同的层面上，设计者可以根据需要提出新的结构或者是选择合理模型。对于第一层面-构件和连接，列举了几种设计中常碰到的问题，本文综合诸多文献提出了解决办法。对于第二层面-单元，本文认为新提出的诸多结构都是从这个层面产生的。第三层面是第二层面的深化，它的实质是将单元层面的单元构件刚片化，采用超单元思想增大了单元库的范围从而提高了新结构产生的可能性。第四层面研究整体的组织形式。 本文提出并设计了四种可伸展结构方案，其中第一个以三棱柱为单元组建伸展臂，其结构刚性较高。它主要解决的问题是初始驱动力的问题，研究中发现采用中间节点设置扭簧能够显著地降低初始启动力矩，结构的动力特性体现为扭转变形。第二个模型首次采用的三杆铰是一种新结构尝试，它具有良好的三向刚度，与剪式铰相比，它的变形大一些，但质量较轻，动力特性较好。第三个模型主要解决的问题是曲面构筑，本文发展的单元等投影尺寸膨胀法可以简练的解决这个问题，它遗留的主要困难在于解决超单元间的协调。本文还给出了这种抛物面结构的最佳吻合抛物面的计算步骤。最佳吻合抛物面的计算表明结构自重对于型面的影响是不可忽略的，同时得出是否把对角杆视为杆件并不显著影响结论。第四个模型是四面体单元组合结构，其主要解决的问题是整体折叠准则，它采用腹杆等长，上下弦杆对折的办法，并以此为根据设计整个模型。 空间可伸展结构运动力学分析对于掌握可伸展结构对星体运动的影响是至关重要的，本文采用达朗贝尔-拉格朗日原理推导Kane方程能有效的解释无功力和去除理想约束反力的影响。本文共有六种方法参与比较，依次是Newton-Euler方程、D’Alembert原理，Lagrange方程，Hamilton正则方程，Gibbs方程和Kane方程。比较结果是就复杂结构来说，采用Kane方程是较优的选择。采用Kane方法时，虽然能够灵活选取广义速率是一个优点，但是对于计算机应用来讲，程序员希望广义速率的选取能够规范化，如果需要灵活选取显然不利于编程，本文讨论了如何利用优点，避免缺点。 在选定Kane方法后，本文系统建立Kane方程的Huston形式，采用低序体阵列能够有效的描写树形多体系统。偏角速度阵列是形成动力学方程的基础，而转换阵则是简化矢量运算和求导运算的有效工具。通过一系列推导可以看出，Kane方程Huston形式具有与一般振动方程相同的形式，故而关于一般振动力学方程的理论可以应用到多体系统上。Kane方程的Huston形式还可以求解少量的闭环系统，求解前，需要将系统等效成带闭环约束的开环系统。采用类似于有限元分析中的后处理法可以实现多体分析中的计算机自动处理。处理约束有两种有效方法，分别对应于需要求出约束反力和不用求出约束反力。采用第一种约束处理方法时，当系统约束有增加时，只需修改B矩阵项即可。对于铰接点和柱铰点等姿态约束节点，Huston形式具有不必另外列写约束方程的优点，全部自动满足。胡其彪：空间可伸展结构的设计及动力学分析研究 浙江大学博士学位论文2001年4月 但是采用Huston形式描述可伸展结构存在诸多的困难，对于比较简单的开环伸展结构采用Huston形式是比较好的选择。本文首次提出Kane方程的FCC形式，它利用刚体上的两个固定节点和一个附着的单位矢量来描述刚体，整个系统则通过这些节点和单位矢量完整描述。采用FCC方法描述多闭环系统最大的优势在于不必将系统等效，这对于多闭环系统有重大意义。采用FCC的第二个优点是求解方程的解答就是设计中要使用的关键数据，不象Huston形式点求解结果还需进一步转化才能被工程师们使用，缺乏直观性。 弹簧连接对于计算的影响是不可忽略的。对于弹簧的连接可以采用简化计算方法。采用子结构凝聚自由度法，可以方便的对结构进行分块，从而实现对于特殊节点的处理，本文的方法如果进行推广，可以类推柔性连接的各个自由度或几个自由度组合的于结构矩阵。采用于结构法推导的矩阵可以很方便的模拟节点从铰接到刚接的连续变化，这对于钢结构中的柔性连接模拟有借鉴作用。 对于整体可伸展结构，本文提出的采用裙边和加劲肋的方法可以达到增强刚度的目的。为了提高结构的可折叠性，在裙边处开设缺口。本文详细的分析了有无裙边、壳厚、肋数、肋宽、裙边宽、缺口数对结构的变形和自振特性的影响，并对系统的可折叠性进行了几何非线性分析。得出的结论是：有无裙边对改善结构动力特性效果最显著；对于sin口径的抛物面天线，采用 3tTun厚度，2根加劲肋，肋宽为 200mrn，裙边宽为 1更多还原

【Abstract】 The deployable space structure is a new type of space architecture that developed expeditiously in recent 40 years and is used in from communication satellite to space station widely. New space technology requires lighter weight and higher shape accurate reflectors, bigger stowed volume ratio and high reliability for deployed, etc. In this dissertation a systematic research is made in construction ideas, design practice, deploying kinetic and dynamic analysis, and intrinsic structure mechanics problems for deployable structures.A classification is made to deployable structures on the viewpoint that the person with a fine classification knowledge can have a good idea to choose a practical method to design and realize the deployable structures. Further, concept design for deployable structure is developed in this paper. Here a four-layer hierarchy concept for concept design is presented. In different layer designer can select a rational model or bring forth a new model and only when he wake up to the hierarchy concept, he can put all irons in the fire. About the first layer, some frequently asded questions(FAQs) are enumerated. At the same time according solution are released. That a design is successful or not has a tight connection with member design. About the second layer, it is the right place new idea comes from. Later a tri-rod-hinge structure is brought forward, which is just based on the second layer. About the third one, name as extra-element, differs from the second one just on that the former has a rigid piece. Extra-element concept enlarges the element library and enhances the possibility for inventing new structures. As to fourth layer, the light is put on integration the element and extra-element. In fact, many designs can not depend on a type of element or an extra-element. A good arrangement is necessary for the fourth layer concept design. Later a scheme for stiffness improvement of integration deployable structures is shown. The scheme is grounded on the concept design.Four kinds of schemes of deployable structures are proposed. The first one is deployable prism-shaped mast. The main effort is to solve the initial driving force. During the research we observed that the torsion spring at the middle node could lessen the scale of driving force obviously. Model dynamic appearance is torsion deformation. To minish the friction force between the slide node and horizontal strut, the least contact area is necessary. The second one is a tri-rod-hinge model. It has a better 3-D stiffness, dynamic characteristic and lighter mass compared to scissor-like model. The third model is hexahedron element with flexible strut. Only diagonal strut has tension spring, so that the diagonal strut can change its length by straight-line spring. As the pre-tensioned springs shrink, the structure deploys in synchronization. Until reaching its design position geometry, it is locked into a stable structure. It has character of high stiffness, high stability and can be manufactured easily. The main job is to construct concisely bend face by method named Equal Projection Dimension and Equally Bulging Scale (EPDEBS). But there is a remaining question how to deal with harmony among the elements. The numeration process of best-anastomosed parabolic face is shown and the result shows that the gravity effect is not neglectable and whether treating the diagnose strut as a rod or not has not effects to the result remarkable. The forth model is integrated by tetrahedral elements from central element. The basic tetrahedral element consists of six struts. The length of three abdominal struts is not changed during deploying processing. Other three on the base plane have foldable nodes, which areequipped with a torsion spring, so that tetrahedral element can be foldable. The torsion spring is in pre-stress situation when stowed and deploy automatically after release. The elastic energy can keep the parabolic face. The main job for the model is to determine the guideline for whole deploying. The guideline is that length of更多还原