Prosthetic limbs have come a long way in a very short amount of time. Not long ago, prosthetic hands and arms were clunky, awkward and limited in function. Now, thanks to 3D printing, prosthetics can be quickly and easily custom-fit and even specially designed for functions like playing basketball or swimming. People who have lost limbs are no longer limited in what they can do, as 3D printed prosthetics continue to develop and offer function and mobility that rival that of a natural limb.
One thing that prosthetics haven’t really managed to do yet, though, is restore the sense of touch. The loss of that sense in any limb is a great one; I can only imagine what it must be like to no longer be able to experience texture, warmth, or coolness in one or more extremities. Even that limitation, however, may soon be a thing of the past thanks to a collaboration between the University of Melbourne, the University of Wollongong, and several other institutions coordinated by St. Vincent’s Hospital’s Aikenhead Centre for Medical Discovery.
A group of researchers from the Australian institutions is studying the way the human arm communicates signals to the brain, with the intention of reproducing that signaling process artificially. Right now they’re working on prototyping a robotic arm that would use 3D printed microchips to facilitate communication between implanted electrodes and natural tissue and muscle. The project stems largely from the research of Mark Cook, a neurologist at St. Vincent’s, who used a highly complex set of mathematical models to record and decode the electrical activity happening in the brains of test subjects as they performed different movements. By analyzing the recordings, Dr. Cook was able to ascertain which combinations of electrical signals correlated to which movements.
It’s all pretty mind-blowing stuff – and that’s even before learning about how the researchers intend to facilitate the communication between the brain and the prosthetic. In collaboration with the researchers developed a way to 3D print muscle cells onto microchips. While much of the research remains confidential, the idea is that the microchips will act as conduits enabling communication between tissues and electrodes – between human brain and robotic arm.
“You can listen to the electrical activity and figure out which limb is going to move and which part of the limb and so on,” he said. “We can understand your thoughts and turn them into mechanical action.”
“The artistry at the moment is that we are creating the chip that is able to connect biological and mechanical movement through electronics to create sensation percepts in the brain,” said University of Wollongong professor Rob Kapsa. “We can connect nerves and muscles on a chip and read the signals. We have an electrode system on which we have been able to grow the cells on and been able to read the muscle function coming out of it, and we have created a cocktail that creates nerve-muscle connections which will potentially assist in connection of muscle-based movement with mechanical (robotic) movement.”
Right now, the researchers are experimenting with using electrode technology on prosthetic hands and arms that already exist. Their goal is to have a prototype of a new robotic prosthetic completed in the next year, but that’s only the beginning of what this technology could potentially accomplish. These methods of “translating” brain signals and connecting nerves and electrodes have the potential to regenerate tissue and treat epilepsy, muscular dystrophy and more. We could even see a future in which amputated limbs will be replaced with something that’s much closer to a natural limb than a prosthetic.
“Everyone has their Everest — for me it is building amputated limbs,” said Professor Peter Choong, Director of Orthopaedics at St. Vincent’s. “Science has to go to the absolute extreme to deliver on this. Rebuilding partial or total amputation is really about 3D-printing bone, using stem cells to generate bone, hooking up with artificial muscle, engineering connections and then getting the nerves to join them. That will be the robot. This is a mechanical device that responds to electrical signals, and these electrical signals are thoughts.
“Because these pathways for thought are already there in the form of nerves, it is like a telephone line and we just have to hook it up to the machinery and program it to respond to the signal.Then sensors in the fingers will pick up that you have closed them and send signals back up the telephone line, so you feel it. That is the dream that we want. With the sort of firepower we have around the table, this is something that we clearly can do.”
The Aikenhead Centre brings together several of Australia’s leading biomedical research institutions, which are pushing for a new facility to be built to further expedite the development of technology like the aforementioned. Discuss further in the Australian Researchers Combining Robotics & 3D Printing forum over at 3DPB.com.[Source: Herald Sun]