A navigation system for permanent-magnet-actuated microswarm

Abstract

Micro/nanorobots have significant potential applications in biomedicine. However, their small size and the need for intricate control make long-distance navigation of microswarms composed of such robots challenging in complex environments. To address this problem, we have developed a permanent-magnet-actuated microswarm navigation system to achieve precise control of micro/nanorobots in complex fluid environments. The controlled microswarm is composed of monodisperse Fe3O4@PVP nanoclusters synthesized using the polyol method. These nanoclusters can self-assemble into highly controllable microswarm structures under a rotating magnetic field and are then guided by the robotic system for precise navigation. The system uses visual positioning and motion control to enable real-time dynamic navigation. In experiments, it successfully performed autonomous navigation over a 55 mm distance in a transparent channel, with flow rates ranging from 0 to 10 mm/s. It completed the task in 132 s at an average speed of over 0.45 mm/s, with an average trajectory tracking error of only 0.28 mm. These results demonstrate excellent path accuracy and stability under various flow rate conditions, validating the system’s adaptability and efficiency in fluid environments and highlighting its potential for biomedical applications. This study offers a robust and versatile platform for expanding micro/nanorobot applications in biomedicine.