500m球面射电望远镜(FAST)的馈源支撑系统存在大跨度柔性索支撑结构,馈源仓容易受到外界干扰源的激励引起振动,影响馈源舱内接收机定位和指向的性能和精度。质量阻尼器作为一种有效并且可靠的振动控制设备,得到了深入的研究和应用。本文从质量阻尼器的基本原理出发,初步设计出一种应用于FAST馈源支撑系统的被动和主动质量阻尼器模型。数值分析和仿真实验结果表明质量阻尼器对FAST馈源仓的振动有明显的抑制效果。
The FAST (Five-hundred-meter Aperture Spherical radio Telescope ) focus cabin is suspended and driven by 6 cables, moving on a spherical cap of - 206 meters in diameter. Due to the low stiffness and weak damping of large-span cables, vibrations of the focus cabin are expected normally excited by wind-impact and other disturbances from the capstans, which can significantly influence the pointing accuracy of the telescope. A reaction mass damper is effective and reliable for vibration control. In this paper, designs of reactive mass dampers are investigated to suppress vibration and increase damping. As a result of the numerical analysis and dynamical simulation, we show that reaction mass dampers have satisfied performance in suppressing vibrations of the focus cabin and in improving the pointing accuracy of the telescope.