Run by motors and sensors that transfer muscle movements from the arm into mechanical motion, the standard aluminum myoelectric limb was too heavy and bulky for a child.

 

"I'm not an engineer, but from the very beginning there seemed to be all these ways we could improve prosthetics, from how they fit and look to what they could do, but there was nowhere to go to find out," said Haag, who works in information technology sales for an Atlanta firm called Ripple.

 

Researching the problem online, he came across an organization called Open Prosthetics Project...