How a double amputee manages to control two bionic arms
Les Baugh is the newest face of bionic technology because the researchers from Johns Hopkins equipped him with two innovative bionic limbs that are under direct control to his brain. This represents a major evolution for modern prosthetics. Furthermore, it looks cool and exemplifies how biology and technology can be combined.
The process is the same whether you move and arm made out of stem cells or carbon fiber. First the storm of neural activity is linked with a specific action. This pattern is acknowledged by a network of neurons or electrodes. After this, the information is transmitted to the nearby destination. For common amputees, electrodes will be used, but there are some like Baugh that have some living nerve tissue left over in his shoulders.
The method used is known as targeted reinnervation. This means that the researchers allowed his brain to make the signal recognition and propagation in order to pick up the muscle orders in the shoulder. Here they redirected the nerves onto a not used leftover arm muscle. The difference between using this technique and using cranial electrodes is the fact that Baugh`s digital hop is only shoulder-to-arm, instead of brain-to-arm.
Anyway, when a motor signal arrives in a chemical or digital way, the aim is to stimulate motor proteins in muscles or electric motors in bionic limbs. After this, movement is obtained. Researchers’ state that is almost no difference between bionic and biological movement. The John Hopkins team showed us that a user can handle two MPLs at once and Baugh is the living example that people can adapt to this very quickly.
Those modular arms still need improvement. The hardware and the software that reads neural signals and the electrodes that offer information and algorithms for interpretation need some serious updates. For the moment, Baugh has to pick out each joint he wants to set in motion. This means that in order to pick an object he has to move his shoulder to the right angle, then the elbow, then the wrist and lastly the fingers.
In order to replace all the functions of a limb, you would have to be able to manage at least a dozen muscles at the same time. Scientists already consider this and plan a brand new generation of limbs. So, they hope that the future will come with a bionic arm dexterous enough to complete meticulous tasks. The limbs weigh almost as a real arm and the team plans to dress them in a skin-like material.
If you watch two bionic arms controlled at the same time by a man with little to none experience in using them, you acknowledge the fact that those will eventually get to act and be controlled like a normal arm. Baugh has shown us that there can be integration of gesticulation with thought and speech. This is the main difference between a robot helper arm and an actual limb replacement.