1. Shandong Engineering Research Center for Additive Manufacturing, Qingdao University of Technology, Qingdao 266520, Shandong, People’s Republic of China
2. Institute of Electrical Engineering, Chinese Academy of Sciences, Beijing 100190, People’s Republic of China
3. Qingdao Engineering Vocational College, Qingdao 266112, Shandong, People’s Republic of China