Multi-environment robotic locomotion through integrated pectoral and caudal fin propulsion

Abstract

Amphibious robots, inspired by aquatic and terrestrial animals, play a vital role in advancing robotic capabilities across diverse environments. This study proposes a novel design for stingray-inspired amphibious robots to enhance propulsion efficiency. First, a pectoral fin propulsion system, also known as an undulating-fin system, is introduced, reducing the robot’s size and weight while enabling effective locomotion in both aquatic and terrestrial settings. Additionally, a combined propulsion system integrating undulating fins with dual caudal fins is developed to improve underwater propulsion efficiency further. The performance of the proposed design is evaluated through fluid dynamics analyses and validated with real-world experiments, demonstrating superior swimming speeds, enhanced underwater maneuverability, and versatile motion gaits compared to single propulsion modes. The robot achieves a minimum Cost of Transport of 3.25 for aquatic locomotion and 5.08 for terrestrial locomotion, outperforming several existing amphibious robots. These advancements highlight the valuable insights for the development of efficient and versatile amphibious robots.