Biomimetic Approaches to Underwater Vehicle Propulsion: A Systematic Review of Nature-Inspired Solutions

Abstract

Marine organisms have evolved highly efficient propulsion mechanisms through millions of years of natural selection, offering valuable insights for unmanned underwater vehicle (UUV) design. This systematic review comprehensively examines biomimetic propulsion approaches inspired by aquatic locomotion, spanning fish-like undulatory motion, jellyfish jet propulsion, cephalopod fin-based maneuvering, and crustacean appendage-driven systems. We analyze the hydrodynamic principles underlying biological propulsion including vortex generation, boundary layer control, unsteady thrust production, and energy recovery mechanisms that enable superior efficiency compared to conventional propeller-based systems. The review categorizes biomimetic UUV designs by their kinematic patterns: body-caudal fin (BCF) swimmers mimicking tuna and sharks, median-paired fin (MPF) swimmers inspired by rays and cuttlefish, and hybrid configurations combining multiple locomotion modes. For each category, we evaluate propulsion efficiency, maneuverability characteristics, noise signatures, and operational speed ranges based on experimental and computational studies. Particular attention is devoted to the actuator technologies enabling biomimetic motion including shape memory alloys, ionic polymer-metal composites, dielectric elastomers, and fluidic artificial muscles, assessing their power density, response time, and durability in marine environments. We examine control strategies for coordinating multiple degrees of freedom in biomimetic propulsion, including central pattern generators, reinforcement learning approaches, and hybrid model-based controllers. The review also addresses practical implementation challenges such as waterproofing, biofouling resistance, and scalability across vehicle sizes from micro-robots to large autonomous submarines. Comparative analysis reveals that biomimetic propulsion offers significant advantages in stealth, efficiency at low speeds, and maneuverability in confined spaces, though conventional systems remain superior for high-speed transit. The paper concludes by identifying promising research directions including multi-modal locomotion, adaptive morphology, and bio-hybrid systems integrating living tissues.