DARPA’s Research into the Next Generation of Prosthetic Limbs

The loss of a limb is undoubtedly one of the most traumatic injuries – both physical and emotional – an individual can suffer. Creating artificial limbs to compensate for lost ones is nothing new – peg legs, and wooden hands and arms have been around for centuries. However, the new generation of prosthetic limbs is not seeking to just add a shell of a similar shape to the lost limb. Advances in technology are allowing for the fusion of man and machine to create prosthetic limbs that not only look like human flesh but can also be moved and manipulated just like the limbs they replace.

When the exponential increase in terrorists using IEDs caused a huge spike in the number of soldiers suffering amputations, the U.S. Department of Defense turned to its advanced research division, Defense Advanced Research Projects Agency (DARPA).darpas-bionic-arms DARPA, working together with the John Hopkins Applied Physics Lab, has already created a prototype of an arm that is controlled by the thoughts of its wearer. Yes, just like we wish our hands and fingers to work simply by thinking of an action we want to perform, the patient does not exert any physical force for the device to work. Sensors attached directly to the neural pathways in the amputee’s arm interpret the signals from the brain and relay them to actuators.

The current prototype allows for 360-degree rotation of the wrist and individual manipulation of each robotic finger and thumb. Each finger is equipped with two joints and the thumb with one, so that it is physiologically equivalent to the human hand. The device also attaches directly to the bone instead of through an external harness. This setup is more stable and comfortable than other connection options.

While the transfer of signals to the bionic arm has been achieved, developers are already looking to transform the information exchange into a two-way process. The idea is to allow sensors to send information on texture, pressure and temperature to the brain of the wearer.

DARPA’s ultimate aim is to create a closed-loop system that will integrate prosthetics and their control systems with the biological system. Neural pathways will blend seamlessly with synthetic data transmission cables so there is unprecedented speed and accuracy of signal transfers.

Other researchers are working on synthetic skin to go over prosthetic limbs so that there is no visual indication that it is being worn. It seems that the day is not far when we will be able to shake hands with an amputee and just not tell the difference.