Prosthetic Hand Restores Amputee's Sense of Touch
Luke Arm (Sept. 2009)
How long did Luke Skywalker have to wait for his prosthetic arm? Not long he was back in the action within days it seems.
I’ve been loosely following the Luke Arm - Dean Kamen’s name of the DARPA funded prosthesis. First I’m floored that in 30 months the team could create such a beautiful design (beautiful in an engineering way). The human arm (counting the hand also) has 22 degrees of freedom (DOF) (movements like forearm rotation). The traditional hook and cable prosthetic has just 3 DOF. That hook was designed in the days of sailing ships, updated with aircraft cabling to allow some movement after World War I.
The typical user gives up on the frustrating hook/cable arm after a few years. Why? Kamen’s group think it is the low return on investment (ROI) the arms provide the user. They don’t provide enough benefit (mobility, dexterity, functionality) for their cost - here cost is not money as many are provided by VA benefits - but cost in more human terms, like comfort of the device interface. Just one of the drawbacks; the socket is designed to cup the “stump” and becomes sweaty and slippery reducing functionality and decreasing comfort.
Update: see 3D Printing a Better Socket for Prosthetic Limbs (TED.com) by David Sengeh of MIT Media Lab
Want to see the Luke arm in action? YouTube - IEEE Spectrum (video).
Now what puzzles me is that it took less that 3 years to invent the prosthetic arm but will take at least 3 years in clinical trials (FDA) if there is funding for the trials. DARPA funding does not extend into the clinical trial. But why does this device even require FDA approval and trials?
If this was a game console (Wii or Xbox) controller - like a Power Glove it would not require FDA approval. How is the Luke arm different?
Deka (Kamen’s company) received $18.1 million for a 30 month contract started in 2005, and delivered working prototypes in late 2007. A modular device weighing less that the human arm and nearly just as capable! It appears to be a wonderful invention, waiting on FDA approval to become an innovation.
What’s the difference between invention and innovation? Innovation is when that wonderful idea actually gets to usefulness in society. It is typically a 30 year process between invention and innovation. Will we have to wait another 30 years?
Ray Kurzweil has plotted the exponential curve of innovation for some well know inventions, see: Mass use of Inventions (mass use defined as 1/4 of US population).
More info on the Luke arm and other DARPA prosthetic arm research at IEEE Spectrum.
Update: May 2014 - It appears that the DARPA project is on a fast track - it will not take 30 years.
USA FDA approves Deka to market a prosthetic arm that can perform multiple, simultaneous powered movements controlled by signals picked up from sensors on the user's arm (electromyogram or EMG).
See story and video from re/code:
FDA Approves Robotic Prosthesis Controlled by Muscle Contractions By James Temple
Weird but related - a robotic arm that can catch random objects thrown to it.
Robotic Arm Catches Objects on the Fly
Kids Design Their Own Prosthetics
A Budget Exoskeleton