Scientists have long attempted to imitate nature's efficiency and mechanical elegance — but this project's minuscule machines are powered by actual living tissue. Rashid Bashir, head of bioengineering at the University of Illinois, leads the effort to build "bio-bots" that use muscle cells culled from rats to get around. The muscle is wrapped around a simple, flexible 3-D printed "skeleton," and stimulated electrically; when the muscle contracts, the tiny contraption takes a "step" forward. The speed can be controlled by the frequency of electrical pulses. You can watch it in action here.
"This work represents an important first step in the development and control of biological machines that can be stimulated, trained, or programmed to do work," Bashir said in a news post describing the research, which appeared in the journal PNAS. He envisions such tiny machines working inside human bodies, for instance navigating toward toxins or injuries to administer aid. "This is very promising for medical applications," added co-author and graduate student Ritu Raman. "But why stop there?"
— Devin Coldewey, NBC News