This paper explores online stiffness modulation within a single tail stroke for swimming soft robots. Despite advances in stiffening mechanisms, little attention has been given to dynamically adjusting stiffness in real-time, presenting a challenge in developing mechanisms with the requisite bandwidth to match tail actuation. Achieving an optimal balance between thrust and efficiency in swimming soft robots remains elusive, and the paper addresses this challenge by proposing a novel mechanism for independent stiffness control, leveraging fluid-driven stiffening within a patterned pouch. Inspired by fluidic-driven actuation, this approach exhibits high bandwidth and facilitates significant stiffness changes. We perform experiments to demonstrate how this mechanism enhances both thrust and swimming efficiency. The tail actuation and fluid-driven stiffening can be optimized for a specific combination of thrust and efficiency, tailored to the desired maneuver type. The paper further explores the complex interaction between the soft body and surrounding fluid and provides fluid dynamics insights gained from the vortices created during actuation. Through frequency modulation and online stiffening, the study extends the Pareto front of achievable thrust generation and swimming efficiency.

中文翻译：

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软机器人鱼尾的在线液压刚度调节，以提高推力和效率。


本文探讨了游泳软体机器人在单个尾行程中的在线刚度调制。尽管加强机制取得了进步，但很少关注实时动态调整刚度，这给开发具有匹配尾部驱动所需带宽的机构带来了挑战。在游泳软体机器人中实现推力和效率之间的最佳平衡仍然难以捉摸，该论文通过提出一种新颖的独立刚度控制机制来解决这一挑战，该机制利用图案袋内的流体驱动硬化。受流体驱动驱动的影响，这种方法表现出高带宽并有助于显着改变刚度。我们进行实验以证明这种机制如何提高推力和游泳效率。尾部驱动和流体驱动的加强可以针对推力和效率的特定组合进行优化，根据所需的机动类型进行定制。本文进一步探讨了软体与周围流体之间的复杂相互作用，并提供了从驱动过程中产生的漩涡中获得的流体动力学见解。通过频率调制和在线加固，该研究扩展了可实现的推力产生和游泳效率的帕累托前沿。