Mudskipper-inspired amphibious robotic fish enhances locomotion performance by pectoral-caudal fins coordination

Amphibious robots face challenges in efficiently combining locomotion strategies and coordinating propulsive mechanisms, hindering their locomotion performance similar to amphibian animals. This study presents the design and implementation of an agile amphibious robot inspired by the mudskipper, a highly adaptive amphibian. This innovative robot employs fish-like locomotion underwater and legged locomotion on land to achieve high propulsion efficiency. Furthermore, the maneuverability of the robot is significantly enhanced through the coordination of the pectoral and caudal fins. Our experimental results demonstrate that the minimum cost of transport for terrestrial and aquatic locomotion is 4.56 and 2.02, respectively, outperforming many existing amphibious and unimodal robots. In addition, the robot’s terrestrial and aquatic turning speeds improved by 50.1% and 24.4%, respectively, owing to the effective coordination of the pectoral and caudal fins. Our amphibious robot has great potential for diverse applications and provides valuable insights for the development of advanced and versatile robotic systems.