The Defense Advanced Research Projects Agency or DARPA has set out to develop a mechanical arm with functionality on par with a flesh-and-blood limb by 2009. So far, the researchers at the Johns Hopkins University Applied Physics Laboratory (APL) has already developed a prosthetic arm which allows its user to actually feel an object it grasps.

The forefather of this project, Proto 1, was attached to nerves in the user's chest and shoulder. This paved the way for direct sensory feedback, triggering the sensation of grip in the nerve receptors that map to the missing hand. In addition to this, Proto 1 also allows for more natural walking, since it can swing freely.

Now, APL expects to complete the newest model, Proto 2, by the end of the summer. The arm is said to be stronger, faster and more flexible. In addition to this, it will provide even more sensory feedback, including limb position and temperature.

Of course this comes at a price, users will need to become even more bionic with this new product. The installation of the mechanical arm requires replacing surface electrodes with tiny sensors that will be implanted or injected into the body to allow for better feedback to the user.

This technology looks to provide a very good replacement arm for those who have lost their original limbs. However, it also poses two questions that society will have to tackle eventually. When it [the bionic arm] is further refined, will we be finding people who would willingly swap out their biological limbs for the improved bionic arms? Secondly, is it ethical to do so?