1. Department of Computer Science and Information Engineering and Graduate Institute of Networking and Multimedia National Taiwan University Taipei 106, Taiwan
2. Qatar Campus Carnegie Mellon University Pittsburgh, PA 15289, USA
3. The AI group Stanford University Stanford, CA 94305, USA
4. The Robotics Institute Carnegie Mellon University Pittsburgh, PA 15213, USA
5. The ARC Centre of Excellence for Autonomous Systems The University of Sydney NSW 2006, Australia