One of the wonders of modern technology is its ability to compensate for impaired or missing functions in the human body. Prosthetic limbs, enhanced hearing, cochlear implants, wheelchairs, and exoskeletons are just a few of the amazing developments that allow individuals to live better lives. One area where technology has helped is with impaired vision. The average person relies on the sense of sight for so many important functions, including the ability to walk around and get where you want to go without bumping into walls or furniture or people.
The solution of choice for millennia as been a stick. Sure, the design has changed over the ages to be more ergonomic, but the long cane is the visible badge of the vision impaired. A team at MIT’s Computer Science and Artificial Intelligence Laboratory (CSAIL) are working on a wearable navigation system that offers some advantages over the traditional stick. It relies on a 3D imaging camera that can perceive depth, a small dynamic braille tactile display, and a haptic belt that provides cues to the wearer by vibrating in different locations. These are tied together by a computer that processes the image signals to provide the necessary feedback. Not only does the system signal the location of obstacles, it also does its best to identify them. As a result, it can distinguish between an occupied seat and an empty one. The braille pad also provides information about what sort of object the system has identified, such as a table or chair. The belt signals proximity, with increased frequency and intensity as the wearer gets closer to an obstacle. It can also signal turns when seeking a chair or other desired objects.
The system is designed to work with or without the addition of a traditional cane. In tests, the researchers found that subjects reduced contacts with objects other than what they were seeking by 80%. It also greatly reduced the number of “cane collisions” with bystanders when walking through a hall with other people. Assuming that the system could be miniaturized and made less obtrusive, this sort of navigation system could be a valuable addition for people with impaired vision.
