Soft actuators offer numerous potential applications; however, challenges persist in achieving a high driving force and fast response speed. In this work, we present the design, fabrication, and analysis of a soft pneumatic bistable actuator (PBA) mimicking jellyfish subumbrellar muscle motion for waterjet propulsion. Drawing inspiration from the jellyfish jet propulsion and the characteristics of bistable structure, we develop an elastic band stretch prebending PBA with a simple structure, low inflation cost, exceptional driving performance, and stable driving force output. Through a bionic analysis of jellyfish body structure and motion, we integrate the PBA into a jellyfish-like prototype, enabling it to achieve jet propulsion. To enhance the swimming performance, we introduce a skin-like structure for connecting the soft actuator to the jellyfish-like soft robot prototype. This skin-like structure optimizes the fluid dynamics during jet propulsion, resulting in improved efficiency and maneuverability. Our study further analyzes the swimming performance of the jellyfish-like prototype, demonstrating a swimming speed of 3.8 cm/s (0.32 body length/s, BL/s) for the tethered prototype and 4.7 cm/s (0.38 BL/s) for the untethered prototype. Moreover, we showcase the jellyfish-like prototype's notable load-bearing capacity and fast-forward swimming performance compared to other driving methods for underwater biomimetic robots. This work provides valuable insights for the development of highly agile and fast responsive soft robots that imitate the subumbrellar muscle of jellyfish for efficient water-jet propulsion, utilizing skin-like structures to enhance swimming performance.

中文翻译：

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由气动双稳态执行器驱动的受水母启发的软机器人。


软执行器提供了许多潜在的应用；然而，在实现高驱动力和快速响应速度方面仍然存在挑战。在这项工作中，我们展示了一种模拟水母伞下肌肉运动的软气动双稳态执行器（PBA）的设计、制造和分析，用于喷水推进。借鉴水母喷射推进的灵感和双稳态结构的特点，我们开发了一种结构简单、充气成本低、驱动性能优异、驱动力输出稳定的弹力带拉伸预弯PBA。通过对水母身体结构和运动的仿生分析，我们将PBA集成到类似水母的原型中，使其能够实现喷射推进。为了提高游泳性能，我们引入了一种类皮肤结构，用于将软执行器连接到水母状软机器人原型。这种类皮结构优化了喷气推进过程中的流体动力学，从而提高了效率和机动性。我们的研究进一步分析了类水母原型的游泳性能，证明系留原型的游泳速度为 3.8 厘米/秒（0.32 体长/秒，BL/s），而水母原型的游泳速度为 4.7 厘米/秒（0.38 BL/s）。不受束缚的原型。此外，与水下仿生机器人的其他驱动方法相比，我们展示了类似水母的原型具有显着的承载能力和快进游泳性能。这项工作为开发高度敏捷和快速响应的软机器人提供了宝贵的见解，这些机器人模仿水母的伞下肌肉以实现高效的喷水推进，利用类皮肤结构来提高游泳性能。