A Soft Robotic Jellyfish with Decoupled Actuators for Agile 3D Locomotion

Jellyfish‐inspired soft robots have attracted significant attention for their alternating contraction‐recoil dynamics and efficient solid‐fluid interactions. However, existing designs often suffer from mechanical coupling between locomotion modes, where a single propulsion action simultaneously induces steering and depth changes, making independent control of each mode difficult. In this work, we present a novel soft robotic jellyfish with a functionally decoupled actuation system that separates propulsion, steering, and buoyancy control into independent modules. The propulsion module utilizes pneumatic tentacles with passive valves to generate net thrust via differential drag. A dedicated lateral water‐jet system enables agile near zero‐radius rotation independent of forward speed. Furthermore, a variable buoyancy module allows for active vertical navigation without continuous power consumption. Experimental characterization demonstrates a maximum swimming speed of and a rapid turning rate of . This decoupled architecture significantly enhances the agility of soft underwater robots, providing a robust platform for complex exploration tasks.