Damage due to hypervelocity impact (HVI) of micrometeoroid and space debris (MMOD) is a common threat in the current space environment for any spacecraft orbiting the Earth and for future launches of new spacecraft. For this reason, the choice of structure and protection materials is an important issue during the design and manufacture of spacecraft. These materials must be chosen based on their survivability in the space environment. The probability of an HVI of MMOD is determined based on a specific impact risk assessment procedure. Starting from identification of the most commonly-used materials for the manufacture of spacecraft and sorting them into three main groups; metal alloys, composites and sandwich panels, the present work presents the results of time-frequency analysis of the signals obtained from numerical simulations of HVI. The damage detection method is based on applying a Choi-Williams Distribution (CWD) and a specific TF-Analysis algorithm developed in-house. A student version of LS-Dyna software was used to carry out these numerical simulations. For the case of penetration, the CWD method reveals clear differences in the HVI form and frequency amplitude for one or two materials of each group initially identified. The characteristics of each perforation on the materials investigated are discussed and results obtained are corroborated through analysis of the signals collected during a previous HVI test session.
Keywords: Satellites, hypervelocity impact (HVI), numerical simulations, spacecraft materials
