1. Key Laboratory of Bionic Engineering (Ministry of Education), College of Biological and Agricultural Engineering, Jilin University, Changchun 130022, China
2. Weihai Institute for Bionics, Jilin University, Weihai 264200, China
3. Department of Mechanical Engineering, The Pennsylvania State University, Philadelphia, PA 16802, USA
4. Department of Agricultural and BioSystem Engineering, Iowa State University, Ames, IA 50010, USA