The robot snake in a model of human veins. (Credit: Kim et al., Sci. Robot. 4, eaax7329 (2019))

You probably didn’t picture the robots of the future to be slimy, magnetized snakes. But a hyper-flexible robot modeled after the legless reptiles and designed by researchers at MIT could make it easier to diagnose and treat blood clots, aneurysms and perform other small-scale procedures in the brain.

The device, less than a millimeter thick, was designed to crawl through the narrow, twisting