A review on the multimodal motion hydrodynamic mechanism of the manta ray-inspired underwater vehicle

Bio-inspired underwater vehicles primarily draw on two types of fish propulsion modes: Body/Caudal Fin (BCF) propulsion and Median/Paired Fin (MPF) propulsion. Among them, the manta ray-inspired underwater vehicle, which mimics the manta ray's use of broad pectoral fins to achieve bowed gliding and flapping-gliding alternating motion patterns, has demonstrated outstanding performance in gliding efficiency, flapping maneuverability, and motion stability, making it a current research hotspot. This paper systematically reviews domestic and international research progress in the fields of manta ray biology, hydrodynamic mechanisms of individual swimming, and hydrodynamic mechanisms of collective swimming for manta ray-inspired vehicles, summarizing and synthesizing key achievements and the developmental trajectory in this area. Finally, based on existing research, the paper identifies the main challenges in the study of hydrodynamic mechanisms for multimodal motion in manta ray-inspired vehicles and provides an outlook on future directions.