1. Laboratoire des Systèmes et Energies Embarqués pour les Transports, Higher School of Aeronautical Techniques and Automobile Construction (ESTACA), Parc Universitaire Laval-Changé, Rue Georges Charpak, 53000 Laval, France
2. Department of Mechanical Engineering, University of Bath, Claverton Down, Bath BA2 7AY, UK