1. School of Mechanical and Materials Engineering, University College Dublin, Belfield Campus, Dublin 4, Ireland;
2. Department of Aerospace, Mechanical, and Electronic Engineering, Institute of Technology Carlow, Kilkenny Road, Co. Carlow, Ireland
3. European Space Agency, Keplerlaan 1, P.O. Box 299, NL-2200 AG Noordwijk, The Netherlands
4. School of Mechanical and Materials Engineering, University College Dublin, Belfield Campus, Dublin 4, Ireland