Ben Wang1,2, Yabin Zhang1,2, Li Zhang1,3,4. 1. Department of Mechanical and Automation Engineering, The Chinese University of Hong Kong, Hong Kong, China. 2. Department of Biomedical Engineering, The Chinese University of Hong Kong, Hong Kong, China. 3. Chow Yuk Ho Technology Centre for Innovative Medicine, The Chinese University of Hong Kong, Hong Kong, China. 4. T Stone Robotics Institute, The Chinese University of Hong Kong, Hong Kong, China.