【作者】 储柳；

【导师】 郑长良；

【作者基本信息】 大连海事大学 ， 工程力学， 2012， 硕士

【摘要】 500米口径球面射电天文望远镜是目前世界上最大的单口径望远镜,其在工程技术上的突破和创新将保证其在未来20至30年间保持世界一流地位。FAST馈源支撑系统主要功能是承载和驱动馈源在百米尺度大工作空间内运动,实时地达到毫米级高精度定位。FAST馈源舱结构由四部分组成：STEWART下平台、STEWART上平台、AB轴转环、星型架。其中STEWART上、下平台由六条驱动腿相连构成六轴机器人,实现对安置于STEWART下平台的馈源接收机的精调。本文运用商用有限元软件ANSYS对馈源舱原结构方案进行了校核,以参数化设计语言将上述四部分分块建模,并分别进行了有限元分析,对各部分连接处所对应的节点变形进行了记录和追踪,并提供了四部分结构在各坐标轴方向的变形云图以及位移矢量和云图。将刚度校核后的四部分结构进行组装,建立FAST馈源舱整体结构模型,运用ANSYS后处理模块进行有限元求解。结合优化模块以及截面选择的非连续性,反复迭代对结构进行优化。在优化方案中对STEWART下平台进行了结构概念的重新设计,以满足STEWART六轴机器人六条腿合理、对称地分布,同时在承载9套接收机时受力分布均匀且结构本身对称性良好。对STEWART上平台、AB轴转环以及星型架进行了截面优化,重新选择结构中杆件的截面尺寸,去除了部分冗余杆件,在保证结构刚度以及结构对称性的同时,降低整体结构的重量。将结构优化后的STEWART上、下平台以及AB轴转环三部分进行组装构成DOWN结构,通过DOWN结构的旋转模拟星型架与DOWN结构的相对转动,之后实现DOWN结构与星型架的装配,构成整体模型,通过整体模型的旋转模拟馈源舱整体结构的服役状态,对结构中连接处所对应的节点的变形进行了记录,并提供了整体结构在典型服役环境下的位移矢量和云图。运用ANSYS后处理模块进行模态分析,以分块Block Lanzcos法分别对DOWN结构、星型架结构以及馈源舱整体结构进行了模态分析,分别给出前10阶频率和阵型。更多还原

【Abstract】 Five-hundred-meter aperture spherical radio telescope is the largest single-aperture telescope in the world, the breakthroughs and innovations in engineering technology will maintain the first-class status in the next 20-30 years. The main function of FAST feedback supporting system is to bear and drive the feedback cabin to have the movement in the space of one hundred meters scale, and real-time precise positioning.FAST feedback cabin structure consists of four parts:under-platform of Stewart, up-platform of Stewart, AB-axis structure, star-shaped frame. Under-platform connected with up-platform by six driver legs constituting a six-axis robot, and precisely controlling the feedback receivers. This article checks the original structure design of feedback cabin, using commercial finite element software ANSYS to have finite element analysis, and parametric design language to build models of above mentioned four parts, respectively, records and tracks deformation of the corresponding node of connected places, and provides structure deformation in the axis direction of the cloud images as well as the displacement vector images.Assembled the four parts and established the overall structure model of FAST feedback cabin; obtained the solution of finite elements in post-processing modules; Operated optimization module and considering the non-continuous selection of the cross-section to optimize the structure, Under-platform had a re-designed concept to meet the STEWART six legs of six-axis robot reasonable symmetrically distributed in the structure, the same time carrying the nine sets of receivers by uniform force distribution, and ensure symmetry good. Up-platform, AB-axis structure and star-shaped frame had section optimization, re-selected the section size, removed some redundant parts to ensure the structural stiffness and structural symmetry, and reduce the weight of overall structure.After structural optimization, under-platform, up-platform and the AB axis structure was assembled to constitute DOWN structure, rotated DOWN structure to realize the relative rotation between DOWN structural and star-shaped frame. Then, DOWN Structure and star-shaped frame was assembled to constitute the overall model, rotated the overall model to simulate the service state of the overall structure. Deformations of the corresponding node of connected places were recorded, cloud images in the axis direction as well as the displacement vector images were provided in the typical service environment. Modal analysis(Block Lanzcos Method) was finished by using ANSYS post-processing modules, DOWN structure, star-shaped frame structure and the overall structure of the cabin, had modal analysis, respectively, given in the first ten frequency and formation.更多还原