Development of a bionic jellyfish robot for collecting polymetallic nodules

The polymetallic nodules on the seabed contain rich rare metal elements, which are the indispensable and important strategic resources for human beings' sustainable development. For the task of collecting and exploring seabed polymetallic nodules, a novel bionic jellyfish robot is presented in this paper. Based on multibody dynamics and numerical analysis methods, the key components of the bionic jellyfish robot vehicle system and gripper system have been designed and optimized. A fluid-structure interaction simulation analysis of the bionic jellyfish robot in self-propelled mode is conducted, to reveal the influence of key structural and dynamic parameters such as the opened and closed state of the gripper, the fluctuation frequency of the tentacles, and the fluctuation amplitude on the propulsion effect of the robot. The prototype of a bionic jellyfish robot and a corresponding testing platform is developed. The underwater propulsion and sample collection experiments are conducted and the experimental results show that the robot maximum ascending propulsion acceleration and speed are 27 mm/s² and 33.2 mm/s, respectively. The experiments demonstrate that the robot can complete the task of collecting polymetallic nodule samples stably and efficiently, which will provide a new solution for the sampling of seabed polymetallic nodules.