2025/09/09 by Joost Wijnmalen, Wijnmalen, Joost, Léon Abelmann +3
Engineering · Physics and Astronomy · #Characterization and Applications of Magnetic Nanoparticles #FOS: Physical sciences #Medical Physics (physics.med-ph) #Micro and Nano Robotics #Soft Robotics and Applications
paper · pdf · doi:10.48550/arxiv.2509.07959
openalex publication_date 2025/09/09 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
This study compares the propulsion of helical microrobots based on hard- and soft-magnetic elements under rotating magnetic fields. Results show that hard-magnetic microrobots achieved step-out frequencies and maximum propulsion speeds 4.5 times higher than soft-magnetic microrobots. Below saturation magnetization, soft-magnetic micro-robots demonstrated similar performance irrespective of magnetic susceptibility, high-lighting that torque generation in these materials is purely geometry-dependent. Employing a tapered ribbon design increased propulsion speed by a factor of 3.5 compared to regular helical designs. These results provide a quantitative basis for selecting materials and designs, enabling designers to weigh the propulsion benefits of hard magnets against the biocompatibility of soft-magnetic microrobots.