From deterministic to adaptive magnetic micro-robots

Robotics has long pursued the development of systems that can control physical objects remotely and precisely in diverse environments. With ongoing miniaturization, micro-robots have emerged as promising platforms for a wide range of applications. In particular, magnetic micro-robots are compelling because external magnetic fields provide a wireless and biocompatible means of actuation, overcoming the constraints of on-board power sources in confined and complex settings. Despite extensive studies, the classification of magnetic micro-robots has often remained indistinct. This review seeks to contribute a more systematic understanding by defining four major categories—rigid, reconfigurable, shape-changing, and swarm—while also discussing emerging hybrid systems that bridge these paradigms. We synthesize the fundamental actuation principles and representative designs of each category. By examining the capabilities and limitations of each paradigm, we identify challenges and outline future directions for the advancement of adaptive and intelligent magnetic micro-robotic systems.