1. Shenzhen Institute of Artificial Intelligence and Robotics for Society (AIRS), The Chinese University of Hong Kong, Shenzhen, Guangdong 518129, China
2. Department of Mechanical and Energy Engineering, Southern University of Science and Technology, Shenzhen 518055, China
3. Chinese University of Hong Kong, Shenzhen, Shenzhen 518172, China
4. Multi-Scale Robotics Lab, Institute of Robotics and Intelligent Systems, ETH Zurich, Tannenstrasse 3, CH-8092 Zurich, Switzerland