Magnetic Hammer Drives Tiny Medical Robot Through Brain Tissue

Many medical researchers have experimented with magnetic fields that push and pull tiny robots to move them around inside the human body. In this case, University of Houston researchers also created a “magnetic hammer” inside a bullet-shaped robot that would produce enough force to drive it into animal brains.

The robot contains a stainless-steel bead that is pulled back and forth inside the robot’s transparent acrylic body by directional changes in the magnetic field produced by a magnetic reso­nance imaging (MRI) scanner. When pulled in one direction, the bead compresses a mechanical spring at the back of the robot, which propels the bead forward when released to strike the robot’s front end, hammering it deeper into bodily tissue.

“The robot is the combination of the MRI system and this relatively simple component that could be mass produced,“ says Aaron Becker, an assistant professor in electrical and computer engineering at the University of Houston.