Simplified spacecraft vulnerability assessments at component level in early design phase at the European Space Agency's Concurrent Design Facility

Abstract

During recent years, the state-of-the-art risk assessment of the threat posed to spacecraft by micrometeoroids and space debris has been expanded to the analysis of failure modes of internal spacecraft components. This method can now be used to perform risk analyses for satellites to assess various failure levels – from failure of specific sub-systems to catastrophic break-up. This new assessment methodology is based on triple-wall ballistic limit equations (BLEs), specifically the Schäfer-Ryan-Lambert (SRL) BLE, which is applicable for describing failure threshold levels for satellite components following a hypervelocity impact. The methodology is implemented in the form of the software tool Particle Impact Risk and vulnerability Analysis Tool (PIRAT).During a recent European Space Agency (ESA) funded study, the PIRAT functionality was expanded in order to provide an interface to ESA's Concurrent Design Facility (CDF). The additions include a geometry importer and an OCDT (Open Concurrent Design Tool) interface. The new interface provides both the expanded geometrical flexibility, which is provided by external computer aided design (CAD) modelling, and an ease of import of existing data without the need for extensive preparation of the model.The reduced effort required to perform vulnerability analyses makes it feasible for application during early design phase, at which point modifications to satellite design can be undertaken with relatively little extra effort. The integration of PIRAT in the CDF represents the first time that vulnerability analyses can be performed in-session in ESA's CDF and the first time that comprehensive vulnerability studies can be applied cost-effectively in early design phase in general.