First of all, I would like to express my gratitude to my supervisor. Thank you Pablo for your guidance during this work, for your always positive and constructive feedback and, especially, for the patience and encouragement when I thought nothing was going to work. To my family, for believing in me. Your endless support and encouragement made possible this thesis. To my friends, Irene, Paloma, Alfredo, Victor, Claudia, Maripaz, Sandra, Dani... everytime I saw you on weekends gave me energy to go back to work. To Prado, for the endless support, wise advise and suggestions. To my workmates and friends, Andrea, David, Pablo, Miguel... the coffees and afternoons having a drink or at the rockodrome made Valencia feel more like home and less like my working place. Finally, thanks to David and all the fabrication team that also made possible this thesis.