1. School of Naval Architecture and Ocean Engineering, Huazhong University of Science and Technology, 1037, Luoyu Road, 430074, Wuhan, People's Republic of China
2. Department of Robotics, CNRS-LIRMM-UMII, UMR 5506-CC 477, 161 rue Ada, 34392 Montpellier Cedex 5, France