Millipede-Inspired Multi-legged Magnetic Soft Robots for Targeted Locomotion in Tortuous Environments

Miniature robots capable of untethered operation hold great promise for performing diagnostic and therapeutic procedures in hard-to-reach regions within the human body. Nonetheless, navigating these complex and diverse physiological environments remains a significant challenge. To effectively navigate the tortuous pathways inside the human body, it is essential to equip miniature robots with flexible body structures that can adapt to complex geometries and develop efficient actuation strategies for deformed robots. In this study, we present a miniature soft robot featuring a zigzag body structure, imparting the robot with remarkable deformation capabilities that enable it to adapt to confined and tortuous spaces. This robot is equipped with arrays of magnetic legs, enabling robust locomotion propelled by traveling metachronal waves. We demonstrate that the robot can crawl on both flat surfaces and slopes. Leveraging its in-plane flexibility and discrete actuation system, this robot can navigate through intricate environments with precise control using magnetic fields. Our work provides valuable insights into the development of crawling robots with enhanced agility and adaptability, creating opportunities for their future use in a wide range of biomedical applications.