1. The Key Laboratory of Biomedical Information Engineering of Ministry of EducationSchool of Life Science and TechnologyXi'an Jiaotong University Xi'an 710049 P. R. China
2. Bioinspired Engineering & Biomechanics Center (BEBC)Xi'an Jiaotong University Xi'an 710049 P. R. China
3. State Key Laboratory of Mechanics and Control of Mechanical StructuresNanjing University of Aeronautics and Astronautics Nanjing 210016 P. R. China
4. MOE Key Laboratory for Multifunctional Materials and StructuresXi'an Jiaotong University Xi'an 710049 P. R. China
5. Department of Mechanical Engineering & Materials ScienceWashington University in St. Louis St. Louis MO 63130 USA
6. NSF Science and Technology Center for Engineering MechanobiologyWashington University in St. Louis St. Louis MO 63130 USA