I think I may know what Carnegie Mellon is up to in Pittsburgh, and I'm not sure that it would interfere all that much with what we do at this point. Someone from CMU is going to install an 'experimental' system to assist path of egress for the visually impaired. From my understanding this is app based on either andriod or ios.
There is a convention for the visually impaired coming to a property I work with (Hotel AV) and they are installing the system so that the visually impaired know where to walk their seeing eye dogs (like to the field in which dogs 'walk'). From what I was told, the last time the convention was in they used some kind of buzzer outsize that buzzed 24/7 and another guest got so agitated he ripped it down and threw it over the hill side. Before my time.
A friend of mine worked on a similar project for the Disney parks involving guided tours, talking Mickey dolls, and strategically placed RFID tags. Get close enough to the RFID and Mickey tells you something about the ride or whatever - this was 10-12 years ago. No idea what happened with the project.