Dynamic design of a cube-shaped satellite excited by launch vibrations

Abstract

The objective of this Final Project is the structural design of a small cube–shaped satellite. Its primary structure should endure all launching vibrations. To fulfil that objective, a 3D Model of the satellite and a dynamic analysis must be done. The satellite has been designed as a multipurpose platform, so it can satisfy all possible client requirements in order to put different payloads into orbit. To begin with, a general satellite with an arbitrary payload has been designed with the future intention to adapt the current design to each client if necessary. To address the problem the following procedure has been used. First, and with a multi–platform CAD/CAM/CAE commercial software suite called CATIA (Computer Aided Three–Dimensional Interactive Application) a Computer Aided Design Model must be designed. Later, once the parameterized model is created, the engineering simulation software (CAE) ANSYS will be used to study the structural behaviour of the satellite during launch. The scope of this project is to design a multipurpose satellite bus that satisfies the conditions of the ASAP Document (see Section 6.1). That is, a satellite which can withstand all inertial forces and loads during launch in the 0–100 Hz spectrum, with a correctly aligned center of gravity, small enough moments of inertia, and with its natural frequencies above a certain value for each axis. The bus must fulfil the specifications given by the corresponding launch vehicle1 manufacturer, so to choose the launch vehicle, a comparative study has been made between the different options evaluating reliability, availability of the information offered and payload requirements. Once this study has been carried out, the most restrictive launcher has been selected. This has been done in order to be able to use a wider range of LV.