Multi-frequency dynamic absorber for improved spacecraft comfort during the launch phase

In this paper, a methodology to design a multi-frequency dynamic absorber for spacecrafts during the launch phase is presented. A dynamic absorber is a mechanical device which is able to reduce the magnitude of vibration imposed upon a primary structure. The modelling of dynamic coupling between the absorber and satellite is carried out via finite-element (FE) analysis of the coupled structure. The satellite response has been calculated to identify the contribution of the dynamic absorber and to quantify how such a device can improve the overall mechanical environment for the spacecraft during launch. Indeed, an analytical model is used to find relations and conditions to tune the multi-frequency absorber on satellite dynamics in order to improve the payload comfort within a specific frequency band. The feasibility and effectiveness of installing a dynamic absorber has been also illustrated by simulating the behaviour of the coupled absorber-satellite system via FE analysis for an actual case of a satellite vibration control. The results have confirmed the expectations of theoretical approach and modelling and have assessed the capability of the proposed design methodology. © 2012 CEAS.