A remotely actuated magnetic actuator for microsurgery with piezoresistive feedback

This paper reports on a novel magnetic actuator that allows remote magnetic actuation with piezoresistive feedback for remote microsurgery. A novel fabrication scheme of magnetic extrusion of a ferromagnetic column on a silicon nitride cantilever is developed. In conventional magnetic actuator fabrication a high-aspect lithography combined with electroplating is required to make high aspect ratio structures. Here, we fabricated high aspect ratio columns with a suspension of ferromagnetic nanoparticles and epoxy using magnetic extrusion. The fabrication does not require any lithography potentially reducing cost of structures. The magnetic actuation of the magnetic high-aspect-ratio structure mounted on a cantilever was monitored with an integrated strain gauge. The magnetic actuator was remotely actuated under water and generated either acoustic streaming or vigorous agitation depends on the deriving frequency