1. The BioRobotics Institute, Scuola Superiore Sant’Anna, 56127 Pisa, Italy
2. Department of Mechanical, Energy, Management and Transport Engineering (DIME), University of Genoa, 16145 Genoa, Italy
3. Department of Engineering, Nottingham Trent University, Nottingham NG11 8NS, UK
4. School of Engineering, Deakin University, Geelong, VIC 3216, Australia