Bioinspired magnetic soft gripper for rapid and non-injurious capture of deep-sea organisms

The rapid, flexible, and non-injurious capture and sampling of live organisms in deep-sea high-pressure environments is a critical component for establishing environmental baselines prior to deep-sea development operations. Here, we propose and fabricate a bionic multi-fingered magnetically driven soft gripper (MSG) designed for underwater grasping tasks. The gripper adopts a modular, bioinspired multi-finger structure composed of portable magnetic field actuator and high-pressure-resistant silicone elastomer with integrated surface microneedle arrays for enhancing contact friction. Remote, non-contact actuation and programmable deformation are achieved through an external magnetic drive system. The fabrication process, mechanical and magnetic characterization, flow disturbance analysis, magneto-fluid-structure coupling simulations, and grasping experiments on five representative underwater targets were systematically investigated. Structural response, control efficiency, and operational performance were comprehensively validated. Experimental results demonstrate that the MSG can complete expansion-contraction movements within 1 s and achieve high grasping success rates across diverse underwater organisms, with reliable, rapid, and damage-free manipulation. This research establishes a novel technological pathway for soft robotic grasping in underwater applications, offering both engineering value and scientific significance.