1. Department of Mechanical Engineering University of Houston Houston TX 77204 USA
2. Department of Engineering Mechanics and Soft Matter Research Center Zhejiang University Hangzhou 310027 China
3. Materials Science and Engineering Program University of Houston Houston TX 77204 USA
4. Institute of Solid Mechanics Beihang University Beijing 100191 China
5. Department of Chemical and Biomolecular Engineering Rice University Houston TX 77005 USA
6. Key Laboratory of Soft Machines and Smart Devices of Zhejiang Province Zhejiang University Hangzhou 310027 China
7. Department of Materials Sciences and Nano Engineering Rice University Houston TX 77005 USA
8. Department of Electrical and Computer Engineering Department of Biomedical Engineering University of Houston Houston TX 77204 USA