Master thesis and internship[BR]- Master's thesis : Design of a microvibration damper for satellite reaction wheels[BR]- Integration internship

Abstract

Microvibrations management is a very important task in view of improving the quality of operation of modern satellites. Microvibrations can resonate with the structural modes of the satellite and its components and impact the results of the payload. This master thesis describes the development of a microvibration damper for reaction wheels, which are a great source of these vibrations. In the introduction, a review of the state of the art is conducted with the aim of determining which existing solutions seem suitable for the current problem. Other solutions are proposed later in this work. Then, a benchmarking of reaction wheels is performed as well as an analytical modelling of their dynamic behavior, in an attempt to make the analysis of reaction wheels and the subsequent design of a microvibration damper scalable. This work allowed to conclude that this scalability is not possible. The design of the damper is thus conducted for the reaction wheel of interest. An initial trade-off is performed among all the considered vibration isolation systems. Elastomeric materials and their peculiarities are presented and silicone rubber is chosen for the present design. Finite element simulations are performed with the software Siemens NX in order to study the effect of temperature, shape and dimensions, and to compute the transfer function of the reaction wheel assembly (RWA). Based on these analyses, a baseline solution is defined, consisting of four conical elastomeric dampers providing the required attenuation. Finally, the conclusion discusses the limitations of the proposed solution and some recommendations are made for further improvements.