Micro-robotic Swarm of Silicone Oil-based Ferrofluid's Microdroplets

Abstract

Microscale droplet-based robotic systems have emerged as a promising platform for targeted drug delivery, minimally invasive surgery, and lab-on-a-chip applications. Here, we report a novel microrobotic swarm based on microdroplets of silicone oil-based ferrofluid, which exhibits excellent biocompatibility and chemical inertness. By modulating three-dimensional magnetic fields, we achieved reconfigurable self-organized patterns of an aggregated state, a dispersed state, and a chain state. We established a dynamic model and reproduced the three states via numerical simulations. Furthermore, we discovered two locomotion modes: sliding and rolling. Utilizing the sliding mode, we navigated the swarm through narrow and complex channels and accomplished directional transport of bubbles, enabling both translational and rotational movements.