1. College of Materials Science and Technology, Nanjing University of Aeronautics and Astronautics, Nanjing, China
2. National Key Laboratory of Science and Technology on Helicopter Transmission, Nanjing University of Aeronautics and Astronautics, Nanjing, China
3. State Key Laboratory of Mechanics and Control of Mechanical Structures, Nanjing University of Aeronautics and Astronautics, Nanjing, China
4. College of Aerospace Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing, China