针对大射电望远镜FAST的整体变形索网反射面方案的可行性问题,研制开发了一套专门的有限元计算软件,并提出了一个索网反射面拟合旋转抛物面的反馈控制算法。利用有限元计算软件,在索网反射面力学模型上,对反馈控制算法进行仿真实验,以论证该方案的可行性。采用有限元方法对索网进行力学建模和计算,推导了一种适于大范围空间运动的四节点索单元,利用动力松弛法进行三维索结构找形计算。
For the feasibility problem of the cable mesh reflector for a large radio telescope FAST, this paper develops a set of specialized finite element software and proposes a feedback control algorithm for fitting the cable mesh reflector to paraboloid. Simulation of the feedback control algorithm is carried out on the finite element model of the cable mesh reflector utilizing the finite element software to study the feasibility problem. Finite element method is adopted for modeling and simulation of the cable mesh. Thus a four-node cable element suitable for large-scale spatial displacements is derived, and dynamic relaxation method is used for the form-finding of three-dimensional cable structures.