Improvement on the passive method based on dampers for the vibration control of spacecraft solar panels

Abstract

In this study, a passive vibration control method termed as translational root mounting method is proposed and investigated, for suppressing the low frequency vibrations of spacecraft solar panels. The translational root mounting method employs dampers installed at the roots of solar panels to dissipate the dynamic energy. The key of translational root mounting method is that translational root mounting method modifies the fundamental mode shape of the solar panel, by releasing the translation freedoms at its root. The root of the solar panel then has translational freedom instead of rotational freedom. As a result of mode shape modification, the translational root mounting method enables the root dampers to have sufficient working stroke, however without obviously reducing the solar panel’s fundamental frequency. Finite element model of a satellite solar panel with the length of 7 [Formula: see text] is established. Applying the finite element model, the limitation of a conventional passive vibration control method based on rotational root mounting is illustrated. To verify and illustrate the principle of translational root mounting method, the free vibration of the 7 [Formula: see text]-length satellite solar panel controlled by translational root mounting method is analyzed by finite element method. Finite element analysis (FEA) results indicate that the effect of a conventional passive control method is not obvious unless dampers with quite large damping coefficients are employed. In contrast, applying dampers with much smaller damping coefficients, the effect of translational root mounting method is fantastic comparing with the conventional passive method. To optimize the translational root mounting method and theoretically compare it to the conventional passive vibration control method, the solar panel is simplified into a non-linear one-degree of freedom system, and the analytical solution of its low frequency vibration is derived. Applying the analytical solution, it is found that damping ratio of the whole solar panel system does not increase with the damper’s damping coefficient, instead there are optimum values of damping coefficient. Applying the translational root mounting method, for the discussed 7 [Formula: see text]-length satellite solar panel, the damping ratio of which can be elevated from 0.0027 to 0.326.