Did 3D-printed guns make you nervous? Too bad. Now watch this 7mm robo-critter crawl.

University of Illinois has developed a “Bio-Bot.” It’s body is a biological machine, made from 3D-printed flexible hydrogel. It is then injected with rats’ heart cells, which consume microscopic nutrients and “beat,” bouncing on the “bones” as if it were springboards. This gives the asymmetrical, flexible legs of the Bio-Bot the necessary kick they need to begin to “walk” at 236 micrometers per second.

Up next: The future. Organic-based robots, clone muscle, 3D printed bones. Oh, they’re coming. Better close up your face hole. (Image: Phys.org)