Sensing robots and smartphones help navigate the blind

Robots use gyroscopes and accelerometers to monitor their speed, location and to keep track of their position. Now, these technologies are being employed to help those who are blind navigate indoor and outdoor spaces.

Helen Knight, a writer for “New Scientist,” wrote about one such system, being developed by Edwige Pissaloux and colleagues at the Institute of Intelligent Systems and Robotics at the Pierre and Marie Curie University in Paris, France, that consists of a pair of glasses equipped with cameras and sensors like those used in robot exploration.

Unveiled at the Massachusetts Institute of Technology this month, the system features a pair of 3D glasses that produce a map of the user’s environment and their position in it that is constantly updated, simplified and displayed on a handheld electronic Braille device.

It could eventually make it so that people who are blind could go wherever they wanted unaided Pissaloux said.

“Navigation for me means not only being able to move around by avoiding nearby obstacles, but also to understand how the space is socially organised,” Pissaloux said, “for example, where you are in relation to the pharmacy, library or intersection.”

On either side of the glasses sits a camera that generates a 3D image of the scene. A processor analyses the image, picking out the edges of walls or objects for example, which it uses to generate an image. Gyroscopes and accelerometers keep track of the users location and speed. This information, combined with the image, is used to determine the user’s position in relation to other objects.

The system generates about 10 maps per second which are translated to the Braille device in the form of a tactile map. The Braille pad consists of an 8-centimeter-square grid of 64 taxels – pins with a shape memory alloy spring in the middle. When the Braille pad is exposed to heat, the pins rise forming boundaries. Pissaloux said the Braille version of the map is updated fast enough for a visually-impaired wearer to pass through an area at walking speed.

While this new technology is no doubt exciting, David Ross at the Atlanta Vision Loss Center in Decatur, Georgia said that it must be configured to meet a wide variety of needs.

“”Sensing systems developed for mobile robots may have some application,” Ross said, “but must be adapted considerably to suit a wide variety of human needs and situations.”