1. Center for Self‐Powered ActuationDepartment of Biomedical EngineeringHanyang University Seoul 04763 South Korea
2. Department of Physical EducationDepartment of Active Aging IndustryHanyang University Seoul 04763 South Korea
3. Australian Institute for Innovative MaterialsARC Centre of Excellence for Electromaterials ScienceUniversity of Wollongong Wollongong NSW 2522 Australia