Evolution of maneuverability for biomimetic underwater soft robots

The success of biomimetic unmanned underwater vehicle (UUV) missions depends on their turning performance in confined regions without causing unprecedented disturbances to their surroundings. In this paper, we present an efficient computational model for fully resolved simulations of maneuverability and agility for complex deforming swimmers, and visualize their precise hydrodynamics with quantification of vortex formation and shedding processes during turning motion. We implemented a new momentum redistribution method to couple three-dimensional fluid–structure interactions within the OpenFOAM platform. We demonstrate the accuracy of our model by considering challenging benchmark simulations of the maneuverability of batoids and validated them with particle image velocimetry observations of natural species. Furthermore, we explore the development of batoid-inspired UUVs utilizing efficient turning maneuver strategies. We present the effects of morphological features, such as extended fin span, tail actuation, and hydrofoil shaping, on turning parameters and swimming performance. Quantitative results demonstrate improved hydrodynamic performance in the hydrofoil-shaped model, with a peak forward velocity of 1.5 BL·s−1 and a turning rate of 26.25°/s. The solver demonstrated robust numerical stability, achieving periodic force convergence within four cycles and efficiently capturing full six degrees of freedom motion under complex, unsteady flow conditions. This study enables the accurate and precise development of locomotor kinematics for biomimetic underwater vehicles, particularly in scenarios involving multiple deforming bodies, such as swarm behavior in batoids.