Dynamic characteristics and influencing factors of azimuth axis of a new antenna pedestal

Abstract Based on the finite element method, the dynamic characteristics of the azimuth axis of an antenna pedestal were studied. With the help of modal analysis module of finite element software, the modal natural frequency and modal shape of the structure were obtained, and the influence of structural size parameters on its dynamic characteristics was also investigated. Through the research, it can be concluded that the first six natural frequency values of the azimuth axis are 220.21, 220.24, 1178.2, 1519.9, 1531.3, 1531.3 Hz. And the first six modes are shown as follows: the first and second order is the swing mode of the axis, the third order is the up and down stretching mode of the azimuth axis, the fourth order is the torsional vibration mode of the azimuth axis, and the fifth and sixth order are the first bending vibration mode of the azimuth axis. The first and second order natural frequencies of the axis decrease with the increase of size parameters d2 , l1 and l2 , and increase with the increase of size parameters d1 , d3 and d4 . The analysis results provide a theoretical basis for the optimization of the dynamic performance of the azimuth axis.