In a huge breakthrough for prosthetics, researchers are developing limbs that can automatically move and reach for things. It’s all in an effort to make the limbs more natural and organic, and it could greatly improve the movement and quality of life for people with prosthetic arms and hands.
Limbs that “see”
Biomedical engineers from Newcastle University with funding from the Engineering and Physical Sciences Research Council have developed a hand that “sees” objects in its environment. Using a camera, the bionic hand takes a picture of whatever is in front of it, analyzes the shape and size of the object, and then automatically triggers movement to grab the object.
Items can be grabbed with one of four movements: a palm-wrist neutral grasp, a tripod movement using two fingers and a thumb, the movement required to grab a TV remote, or by pinching the thumb and first finger together.
This all happens within milliseconds, similar to the way natural limbs naturally grab items without the person even thinking about it. The technology combines artificial intelligence and neural networks to teach computer systems what kind of grip is required for various objects. To account for environmental factors, researchers took pictures of different objects from a number of angles to best understand what object the camera is seeing.
“Using computer vision, we have developed a bionic hand which can respond automatically—in fact, just like a real hand, the user can reach out and pick up a cup or a biscuit with nothing more than a quick glance in the right direction,” said Dr. Kianoush Nazarpour, Senior Lecturer in Biomedical Engineering at Newcastle University. “Responsiveness has been one of the main barriers to artificial limbs.”
The more objects the limb sees, the more it learns and adapts to find the right grip more quickly and naturally over time, meaning that users who grasp similar things on a regular basis could have faster response times than those just starting to use the hand.
The revolutionary technology now moves into testing with patients at the Newcastle Freeman Hospital.
Between the UK and the US, there are more than 500,000 upper-limb amputees a year. Currently, the most ground-breaking prosthetics use electrical activity to connect muscle movement from the stump to movements of the bionic arm or hand, but the movements still tend to be rather jolty and require lots of practice and skill.
To many amputees who are used to how quickly their hands would naturally move to an object, waiting for the muscle movement to translate to the prosthetic seemed slow and burdensome. Researchers hope the new technology will make the entire process much faster and be easier to use.
One of the best parts of the device is that is significantly cheaper than many other prosthetic options, meaning it could potentially be mass produced and used by large numbers of people.
There is still work to be done in the area, and patient tests will be telling in the actual safety and usability of the device. However, the research team already has plans to expand its efforts to create a hand that can sense pressure and temperature and send the data back to the brain as quickly as a natural hand, which could improve the accuracy and possible movements of prosthetic hands.
“It’s a stepping stone towards our ultimate goal,” said Nazarpour. “But importantly, it’s cheap and it can be implemented soon because it doesn’t require new prosthetics—we can just adapt the ones we have.”
If tests prove successful, the new prosthetic limb could change how amputees move, live, and interact and could lead to huge breakthroughs in other areas of prosthetics.