Actuation, sensing, and fabrication for in vivo magnetic microrobots

This paper investigates some of the fundamental design issues related to untethered biomedical microrobots guided inside the human body through external magnetic fields. Immediate application areas for these microrobots include cardiovascular, intraocular and inner-ear diagnosis and surgery. Issues investigated include the effects of magnetic actuation forces and viscous drag forces faced by magnetic microrobots, fabrication of MEMS devices with integrated hard magnetic materials and position sensing of the microrobot for intraocular applications. A new active defocused tracking method is proposed for visually servoing the microrobot in 3D using only a single microscope view.