Magnetically driven soft robots: A review of actuation methods, magnetic material innovations, and medical applications

Soft robots have emerged as a research hotspot in the field of robotics due to their flexibility and adaptability. Magnetically driven systems have found widespread application owing to their penetrability and controllability. This paper presents an in-depth investigation into both permanent magnet and electromagnetic drive mechanisms, comparing their characteristics and applicable application scenarios. It also provides a detailed overview of magnetic soft materials, which are classified into three types (soft magnetic, hard magnetic, and superparamagnetic) based on their intrinsic properties, along with their practical applications. Emphasis is laid on the design and implementation of four novel materials. Furthermore, a critical evaluation is conducted on the applications of magnetically driven soft robotics in the medical field, accompanied by specific case studies in minimally invasive surgery and targeted drug delivery. To ensure objectivity, the paper also incorporates a dedicated section on bias risk and study characterization, presenting both advantageous performance and unintended outcomes. Finally, it outlines future development directions, providing theoretical references and practical guidance for the research, development, and application of magnetic-driven soft robots.