This is the fourth of the biennial Experimental Robotics symposia which are designed to bring together, in a small group setting, researchers from around the world who are at the forefront of experimental robotics research. The symposia are designed to provide a forum for the presentation and discussion of research in robotics that focuses on theories and principles which have been experimentally validated. This proceedings volume includes the fifty-five contributions that were selected by the International Program Committee for presentation at the symposium. The contributions represent work...