New prosthetic limbs can be controlled by the mind NEW YORK � Engineers at Johns Hopkins University Applied Physics Lab have developed a next-generation prosthetic: A robotic arm that has 26 joints and can be controlled by a person mind, just like a regular arm.Researchers think the arm may help people such as Mr Les Baugh, who lost his arms at the shoulder after an accident as a teenager. Now 59, Mr Baugh recently underwent surgery at Johns Hopkins to remap the remaining nerves from his missing arms, allowing brain signals to be sent to the prosthetic.Mr Baugh custom socket can pick up brain signals to control the arms, known as Modular Prosthetic Limbs (MPL), just by thinking about the movements.The lab chief engineer of research and exploratory development Mike McLoughlin said that as the remapped nerves grow deeper, it is possible that Mr Baugh would feel sensation in his prostheses. Each arm has more than 100 sensors, and amputees who have undergone the same surgery reported being able to feel texture through MPL.Patients of varying disabilities have tested the arm at the lab and helped push the design forward. The limb is modular, which means it can be broken off or built up to accommodate people with different needs � from a hand amputee to someone missing an entire arm. Stroke survivors who have lost the ability to move their entire body or parts of it can also use it as a surrogate arm. However, while the limb is fully functional, it faces hurdles such as approval from the Food and Drug Administration, which may mean a clinical trial. Mr McLoughlin also said the cost of the arm needs to be about a tenth of its current price to be viable in the marketplace. There are now about 10 fully functioning MPLs, and each costs about US$500,000 (S$668,000).�We have designed a Maserati, but what most people will want is a good Toyota,� Mr McLoughlin said. �The MPL was designed to be as sophisticated as we could make it, so you could really push the state of the art. But ultimately, for commercialising it, it needs to be a lower-cost design.�The lab has been awarded US$120 million by a programme run by the Pentagon Defense Advanced Research Projects Agency to help wounded warriors, and has worked with technology developer HDT Global to make a prosthetic that mimics the human arm in dexterity and strength.�The long-term goal for all of this work is to have non-invasive � no extra surgeries or implants � ways to control a dexterous robotic device,� said Mr Robert Armiger, project manager for amputee research at the lab. Researchers envision a kind of cap that an amputee can wear that would feed information about brain activity to the robotic arm. The lab is starting to work with industry partners and they hope the MPL, or a version of it, will be available to consumers in a few years.