Los Angeles, CA February 19th, 2015 – Last week, 19 year-old Easton LaChappelle from the small town of Mancos, CO publicly released the blueprints for a $350 3D printed robotic arm he developed. LaChappelle’s story has generated quite a bit of buzz; he has given a TEDx talk and shaken hands with President Obama (both with his own biological hand and his robotic hand), and most recently was featured in a new Uproxx video series called Luminaries”. He has decided to make the plans to build and assemble the arm available on his website.The arm is made largely from 3D printed materials and moved by hobby servos and fishing line. While the arm lacks many of the features that high-end prosthetics and myoelectric devivces boast, it could be a more economical solution for patients who can’t afford the high costs of obtaining and maintaining traditional prostheses.This isn’t the first we’ve seen of 3D printing in the realm of prosthetics. Limb and hand prototypes have been produced before by several individuals, and a non-profit group called e-NABLE dedicates itself to connecting 3D printing enthusiasts with individuals who suffer from limb loss, especially children.LaChappelle’s arm is unique in that it is one of the first designs that falls between the extremes of advanced myoelectric prosthetics and rudimentary 3D printed limbs. His design is relatively simple and intended for patients that can’t afford a traditional prosthesis (let alone an advanced myoelectric one), but includes more degrees of freedom and motor functions than the most simple 3D printed hands like the ones made by e-NABLE volunteers.The largest claim that LaChappelle makes of his design, however, is that the arm can be controlled by the user’s brain, with no surgery or device implantation necessary.Using an EEG system (similar to the Emotiv EPOC) to monitor and broadcast the user’s brainwaves and an Arduino hardware and software platform to interpret the signals, LaChappelle’s arm can be controlled entirely with the patient’s own brain.Currently available myoelectric prosthetics work with electrical sensors placed on the arm or chest that detect muscle movement and, in turn, translate that to some movement in the device. The bebionic3 by RSLSteeper, for example, is one of the most advanced prosthetic hands available. The user tells the hand how to move and what grip position to assume by using patterns of muscle flexing in the terminal limb and by manually adjusting the thumb position with the contralateral hand. An entirely brain-controlled device has a higher theoretical ceiling in terms of the amount of control and different movements the user could induce, and an EEG system avoids the very painful innervation (or “nerve re-awakening”), which are sometimes necessary for devices like the Modular Prosthetic Limb (MPL) developed at Johns Hopkins, or device implantation that is necessary with the BrainGate system.The problem with EEG is that it reads activity levels in fairly large areas of the brain, and the total amount of commands the user can issue are limited by the number of channels. This leads to a lot of feedback, which generates sporadic, unwanted movement from a robotic arm, and limitations in the degrees of motion and functionality of the arm. There are some workarounds for these issues; scripts can be programmed to filter out feedback, and users can be taught to give commands effectively. A TED talk by Emotiv founder and CEO Tan Le demonstrates how the EPOC can be trained to recognize thoughts or facial patterns, which can then be mapped to specific commands in a virtual system or to an electronic device.Even with these adjustments, however, LaChappelle’s arm has yet to be proven for use as a prosthesis. To be truly considered a prosthetic arm, and not merely a robotic arm, there should be minimal effort and concentration required by the user. The prosthesis should be something that can naturally and easily replicate a number of human functions. The “Luminaries” video includes a brief demonstration of a man by the name of Rich Stewart using an EEG system to pick up a lightbult with LaChappelle’s arm, but it requires intense concentration and the movements are awkward and unnatural.Admittedly, LaChappelle has not explicitly stated that the arm can currently be used as a prosthesis, and at the time of this writing, the software he has developed to control the arm has yet to be released, so it is hard to say for certain how this project will look moving forward. As is often the case when science and the media collide, his story has been sensationalized a bit. In the same video, both Stewart and LaChappelle seem to indicate that the EEG control aspect of the arm is very much a work in progress. But if his releasing of the plans for printing the arm are any indication, it’s fair to assume he will be making the software related to the EEG control available as well.That is perhaps the most exciting part of LaChappelle’s story, his intention to keep everything open-source. Open-source projects have produced some very impressive, widely used software, among them the Linux OS, VLC media player, Firefox Internet browser, and Audacity audio editor. Bringing medical devices into open-source means thousands of users worldwide can tinker with and contribute to LaChappelle’s arm, removing bugs and adding functionalities that perhaps he missed. The rapidly developing field of neuromodulation and brain-computer interfaces certainly could benefit from additional input in the design process.There is a large unmet need for this type of device. According to the Amputee Coalition, there are almost 2 million people in the U.S. living with limb loss, and an additional 185,000 amputations are performed each year. The National Center for Health Statistics estimates that 20 – 30% of these are of the upper limb, meaning there are currently ~500,000 individuals with upper limb loss, and an additional ~47,000 procedures performed each year.Prosthetic devices, especially myoelectrics, are expensive and can require regular maintenance and servicing. Commercially available prostheses and myoelectric devices range in price from ~$3,000 to ~$30,000, and currently in-development advanced bionic arms, such as the Johns Hopkins MPL and the DARPA funded DEKA arm, are projected to reach upwards of ~$100,000. Individuals who are affected by limb loss from an early age would need several prostheses over the course of their life as they outgrow old ones.By keeping this project open-source and not manufacturing anything himself, LaChappelle is able to eschew many of the development and business costs that drive up the prices of commercial devices. Outside of development, the hardest aspect of a device like this would be physically printing and assembling it, which requires access to a 3D printer and a bit of craftiness, but this is the sort of project a robotics hobbyist or college group could handle and would likely enjoy working on.Economy prosthetics offer considerable quality of life improvements for individuals who otherwise wouldn’t have access to them, and adding even basic brain-controlled motor functions could introduce some elementary level of utility that is currently only available in myoelectric devices. The specificity limitations of EEG, at least in its current state, may prohibit LaChappelle’s arm from being the answer to that need, but it’s likewise unfair to assume there won’t be any significant contributions to the world of prosthetics and brain-computer interfaces from the project. The Wright brothers certainly didn’t start by building a 747.And while it seems LaChappelle has no intention of commercializing this venture in any capacity, it’s an important step in moving the prosthetics industry forward. 3D printed prostheses have all the makings of a true disruptive innovation (as described HBS professor Clayton Christensen).It will be interesting to follow how this arm, especially with the input of new contributors, and also keep tabs on any new projects from LaChappelle’s company, Unlimited Tomorrow.Disclaimer: Some of the companies listed above may be DeciBio clients or customers.

Author: Anthony DeBenedetti, Analyst at DeciBio Consulting, LLCdebenedetti@decibio.comConnect with Anthony on LinkedInwww.linkedin.com/in/addebenedetti/enThanks to Pierre Asselin of ReWalk Robotics for his input.