Oak Ridge National Laboratory's robotic prosthesis looks like something out of medieval times—a hand clad in chain mail more appropriate for wielding a broadsword than a mug of coffee. Both the underlying skeleton and thin, meshlike skin are made of titanium to make the hand durable and dexterous while also keeping it lightweight. The powerful miniature hydraulics that move the fingers rely on a network of ducts integrated into the prosthesis's structure—no drilled holes, hoses or couplings required.