Through thousands of years, all living organisms including humans have undergone evolution. This is to cope with the constantly changing environment we live in. Scientists say that human beings used to have a tail.
Most quadrupedal animals-like cats and dogs-have tails and they use this part of their body mainly to counterbalance the weight of their heads. As humans only walk on two legs, our center of gravity passes through our spine, so another appendage is not necessary to play the same role as tails do with other animals.
Recently, however, researchers at Keio University in Tokyo have created a tail-like appendage worn at the waist. As they presented at a recent conference, the additional jointed appendage could help people with problems in balance stabilize their stance. They also said that it could provide another layer of safety for people in construction or other physically challenging nature of work. The designers explained that upon swinging, the center of gravity of a person changes. A tracker, worn on the trunk of the user, can approximately identify the center of gravity and dictates the action of the robotic tail.
One of the researchers, Junichi Nabeshima, states that they copied the structure of the tails of seahorses, and not of monkeys. This is because the square-shaped vertebrae provide additional strength. The robotic tail is made of a sequence of artificial vertebrae, which are actuated by artificial muscles. The 'muscles' are made of pneumatically controlled balloons that are placed in strategic locations of the robotic tail so that they contract and expand according to the amount of compressed air fed to the system through hoses. They called their prototype the Arque: Artificial Biomimicry-Inspired Tail for Extending Innate Body Functions.
With another objective that is the complete opposite of the previous one, the robotic tail can also disturb one's balance. This is relevant for some fields such as in virtual reality. The researchers looked at the disruption of balance as a way to provide realism in virtual reality games. With this idea, they tested its effect. A user wore a virtual reality headset and played a game while wearing the tail. The tail swung around, causing the player to lose balance.
Of course, technology such as this one would receive different reactions. Fast Company, for example, asked if it would be socially acceptable to wear this in public without looking like a cosplayer. On the other hand, some people, like bioengineering professor James Patton of the University of Illinois, praised the creativity of the idea.
