Multimodal Motion Magnetically Actuated Microrobot Based on Heterogeneous Magnetization Design

Magnetically actuated microrobots have shown great promise in medical diagnosis and therapeutic applications due to their miniature size and non-invasive controllability. However, conventional rigid microrobots face significant challenges in navigating natural orifices, exhibiting limited adaptability and struggling to perform complex biomedical tasks. Flexible magnetic microrobots, while offering better compliance with biological environments, often suffer from poor environmental adaptability, limited controllability in multimodal locomotion and difficulties in integrating actuation and functional operations. To address these limitations, this study proposes a novel design strategy combining heterogeneous magnetization and soft-material fabrication techniques to develop two functional microrobots: a quadruped crawling microrobot and a starfish-inspired grasping microrobot. Under the control of a triaxial Helmholtz coil system that generates programmable dynamic magnetic fields, the microrobots demonstrate versatile locomotion modes, including rolling and crawling. A real-time vision-based servo system is integrated to monitor the microrobot's motion and enable autonomous decision-making at branched pathways via predefined motion judgment points. Furthermore, the proposed system supports adaptive mode transitions in response to complex and unstructured environments, paving the way for intelligent operation of flexible microrobots in biomedical scenarios.