1. School of Engineering and Technology, China University of Geosciences (Beijing), Beijing, China
2. Anhui Province Key Laboratory of Special Heavy Load Robot, Anhui University of Technology, Ma'anshan, China
3. Biorobotics Institute and the Department of Excellence in Robotics and AI, Scuola Superiore Sant'Anna, Pisa, Italy
4. State Key Laboratory of Intelligent Technology and Systems, Beijing National Research Center for Information Science and Technology, Department of Computer Science and Technology, Institute for Artificial Intelligence, Tsinghua University, Beijing, China