Micro-scallop robot can swim through blood, eyeballs

Some of us might imagine robots to be big hulking contraptions of mass destruction, but one of the applications of robotics and science goes in the opposite direction, scaling down these objects so that they could be used for medical purposes. But alas, the laws of physics, as often is the case, hinder instead of help, preventing microscopic robots from swimming inside our bodies for whatever purposes. Prof. Peer Fischer and his research team at the Max Planck Institute for Intelligent Systems in Germany, however, might have found a way around that limitation.

The solution lies in the fact that most of our body liquids, like blood, joint fluid, eyeball liquid, do not behave like water. They fall under a category called non-Newtonian liquids. Newtonian liquids like water behave as you would expect, and robots of small sizes traditionally have difficulty navigating through it. Non-Newtonian liquids, on the other hand, actually change their behavior depending on some factors. For example, the more force you exert on it, the more solid or viscous it becomes.

The scientists have also taken inspiration from the scallop, the only bivalve that can swim in water with a reciprocal motion, that is, like clapping their shells. In water, such a kind of motion is futile for swimming. In non-Newtonian liquids, it works quite well. The tiny scallop is controlled by an external magnetic field, but only for controlling its rate and the energy it receives. It doesn't pull the micro-scallop in a certain direction. In truth, this robot can swim by itself.

The design of the robot is far from finished and it is definitely not ready to go for a dip in your eyes. A lot of optimizations can still be done on the robot. Plus, the researchers are sharing this more as a blueprint for future micro-robots rather than as a specific robot with a purpose. As to what that purpose will be, only time and science will be able to tell.

SOURCE: IEEE Spectrum