Laboratory for Biological Systems Analysis, Department of Mechanical Engineering and Mechanics, Drexel University, Philadelphia, PA, United States of America.
Museum of Comparative Zoology, Harvard University, Cambridge, MA, United States of America.
Bioinspir Biomim. 2024 Jan 24;19(2). doi: 10.1088/1748-3190/ad1dba.
Fish coordinate the motion of their fins and body to create the time-varying forces required for swimming and agile maneuvers. To effectively adapt this biological strategy for underwater robots, it is necessary to understand how the location and coordination of interacting fish-like fins affect the production of propulsive forces. In this study, the impact that phase difference, horizontal and vertical spacing, and compliance of paired fins had on net thrust and lateral forces was investigated using two fish-like robotic swimmers and a series of computational fluid dynamic simulations. The results demonstrated that the propulsive forces created by pairs of fins that interact through wake flows are highly dependent on the fins' spacing and compliance. Changes to fin separation of less than one fin length had a dramatic effect on forces, and on the phase difference at which desired forces would occur. These findings have clear implications when designing multi-finned swimming robots. Well-designed, interacting fins can potentially produce several times more propulsive force than a poorly tuned robot with seemingly small differences in the kinematic, geometric, and mechanical properties.
鱼类通过协调其鳍部和身体的运动来产生游泳和敏捷机动所需的时变力。为了有效地将这种生物策略应用于水下机器人，有必要了解相互作用的类鱼鳍的位置和协调如何影响推进力的产生。在这项研究中，使用两个类鱼机器人游泳者和一系列计算流体动力学模拟，研究了相位差、水平和垂直间距以及对鳍的顺应性对净推力和侧向力的影响。结果表明，通过尾流相互作用的对鳍产生的推进力高度依赖于鳍的间距和顺应性。鳍分离的变化小于一个鳍的长度会对力产生巨大影响，并且会影响到所需力发生的相位差。当设计多鳍游泳机器人时，这些发现具有明显的意义。设计良好、相互作用的鳍可以产生比运动学、几何和机械性能似乎差异很小但调节不佳的机器人多几倍的推进力。
