These “robot-threads” developed by MIT expand on research done on so-called “hydrogels,” which are materials made mostly of water that work well within the human body. At the thread’s core is a material called “nitinol” that can bend, and is springy, meaning it has a natural tendency to spring back to its original shape when bent.
The material is coated in an ink-like substance, which is then bonded with a hydrogel, thus regulating it in a magnetically manipulable material that can still survive within the human body. Using a large magnet, the researchers could then steer the thread through a demonstration obstacle course they built to show off how it could work in a surgical situation.
MIT’s researchers also note that you can modify the core construction of the robot threads with other materials to serve different functions, and showed this by replacing the nitinol at its center with a fiber-optic filament, which in practice could be used to transmit laser light to blast away a blockage in a brain blood vessel.