针对大射电望远镜(LT)悬索支撑系统特殊的结构形式,对6索组成的馈源支撑系统的静刚度进行分析.首先,对舱索系统静平衡方程沿馈源舱运动方向上求导,同时考虑到悬索刚度随其应力变化而呈现几何非线性的特点,给出了馈源支撑系统静刚度的公式.其次,在上面结果的基础上,分析了一个定点位置下馈源舱在外界扰动下的振动情况,通过与大型射电望远镜50m室外模型振动试验结果相比较,说明了静刚度求解方法的有效性.最后,给出了大型射电望远镜50m模型馈源舱运动空间边缘的悬索应力与馈源支撑系统刚度的关系.
Considering the special structure for the large radio telescope (LT) with large span flexible cable, the stationary stiffness of the cable-suspended-feed system is studied. The nonlinear equilibrium of the cable-cabin system first is derived with respect to the moving cabin's position variables. The stationary stiffness formulation is obtained based on geometrical nonlinear between the stiffness and tension of cable. Then the formulation is applied to analyses vibration of the cabin. A comparison simulation and practical experiment results of LT 50 m model show the validity of the formulation. Additional, the relation of the cable tension and stiffness of the feed system for LT 50 m model is obtained.