1. Robotic Systems Lab; ETH Zürich 8092 Zürich Switzerland
2. Robotics and Autonomous Systems Group; CSIRO Pullenvale, QLD 4069 Australia
3. Department of Mechanical and Process Engineering; ETH Zürich 8092 Zürich Switzerland
4. Institute for Mechatronic Systems in Mechanical Engineering; Technische Universität Darmstadt; 64287 Darmstadt Germany
5. Vision for Robotics Lab; ETH Zürich 8092 Zürich Switzerland