Roboticists and engineers around the world are chasing after the next great prosthesis to help bring autonomy, control, and comfort back to more than 2 million amputees in the U.S. alone. But even the most advanced, fine-tuned robot limbs share one common limitation—the brain.
Advanced artificial limbs can’t help anyone if they can’t speak with the body’s muscles and nerves. Even with all their high-tech enhancements, robotic prostheses are mostly controlled by old-school biology with leftover nerves severed during amputation. After an operation, those signals can be weak and hard to isolate, so some prosthetic scientists are turning their attention to human biology over robotics in the hopes that better surgical amputation will make current prosthesis work even better.
“Why try to replace these mechanisms instead of leveraging human evolution which has spent millions of years to engineer the ability to perform high speed, high resolution communication?” says Shriya Srinivasan, a doctoral candidate at the Harvard-MIT Health Sciences and Technology program.
Srinivasan studies how prostheses can restore the natural push-pull balance among muscles, called an agonist-antagonist relationship, like when our bicep flexes while our tricep stretches (and vice versa). Rebuilding and exploiting these biological relationships will make for better prosthetic control, as Srinivasan explained to Science Friday this past summer.