1. School of Mechanical and Aerospace Engineering; Nanyang Technological University; 50 Nanyang Avenue 639798 Singapore
2. Singapore Centre for 3D Printing; School of Mechanical and Aerospace Engineering; Nanyang Technological University; 50 Nanyang Avenue 639798 Singapore
3. Department of Mechanical Engineering; Khalifa University of Science, Technology and Research; Abu Dhabi 127788 United Arab Emirates
4. Key Laboratory of Flexible Electronics (KLOFE) & Institute of Advanced Materials (IAM); Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM); Nanjing Tech University (NanjingTech); 30 South Puzhu Road Nanjing 211816 P. R. China