Department of Computer Science, The University of Auckland, New Zealand;School of Computing and Technology, University of East London, UK;Dept. of Computer Science and Software Engineering, The University of Melbourne, Australia VIC 3010;Computer Science Department, University of Wyoming, Laramie, USA 82070;Robotics Institute, Carnegie Mellon University, Pittsburgh, USA PA 15213;University of Trento, Povo (Trento), Italy