Even more so than their sighted counterparts, blind people rely heavily on public transport. In a survey of blind youth conducted by the Royal London Society for Blind People (RLSB), however, about half of the participants stated that they were uncomfortable using the London Underground. With that in mind, the RLSB's Youth Forum partnered with the ustwo design firm to create a prototype system known as wayfindr. It uses a combination of Bluetooth beacons, an app, and bone conduction headphones to guide users through the subway system.

The beacons take the form of iBeacon-based Estimote modules (seen below), which are placed at strategic locations around the Underground system. iBeacon is an indoor proximity system developed by Apple, in which Bluetooth Low Energy transmitters are used to notify nearby iOS mobile devices of their presence.

In the case of wayfindr, the app picks up the signals of the three closest beacons, the physical locations of which are already pre-programmed into the software as waypoints. By comparing the strength of those signals, the app is able to triangulate the user's location relative to the waypoints – it's not unlike the fashion in which GPS works, although it utilizes satellites instead of iBeacons.

From there, the app delivers spoken navigational cues to the user, via the AfterShokz brand headphones. Because those headphones work by sending vibrations through the cheek bones, they don't block the ear canals, allowing the user to still hear what's going on around them.

"What we learned whilst tackling this challenge is that young vision impaired people cherish their independence, like all people of their age," said Umesh Pandya of ustwo. "What we accomplished with wayfindr is something that will complement existing efforts by public transport operators to help them achieve it. We have received incredible feedback about it in discussions with these operators and a trial is in the offing."

The University of Nevada, Reno’s Navatar system is also designed to guide blind users indoors (where GPS doesn't work), although it utilizes a combination of digital building maps, the phone's compass and accelerometer, and occasional landmark verifications provided by the user.

More information on wayfindr is available in the following video.

Sources: Royal London Society for Blind People, ustwo