The University of Massachusetts Amherst
University of Massachusetts Amherst

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Ganz to Install Electronic Navigation System for Visually Impaired in MBTA

Imagine being blindfolded and then turned loose to navigate the complex Boston subway system. Your plight might recall The Man Who Never Returned, that classic Kingston Trio song about a guy named Charlie whose fate on the subway was to “ride forever ‘neath the streets of Boston.” Now imagine you can never take off that blindfold. That’s the real-life predicament of any visually impaired person who enters a busy subway station, and University of Massachusetts Amherst Professor Aura Ganz has a brilliant solution.

Called PERCEPT, Ganz’ invention is a seeing-eye directory for the blind and visually impaired which will provide them with verbal directions, electronic signs, and a virtual information booth for finding their way around the subway station.

Ganz, a faculty member in the UMass Electrical and Computer Engineering Department, has received a two-year, $238,321 grant from the Massachusetts Bay Transportation Authority (MBTA) to install a prototype of her electronic navigation system for the visually impaired in the Arlington Metro Station.

When in place, PERCEPT can be utilized by any visually impaired individual equipped with a smartphone, a special Interactive Metro Spaces (IMS) application loaded with pre-set navigation instructions, and a near field communication (NFC) set of standards that allows smartphones to communicate with the PERCEPT NFC tags deployed throughout the station.

As Ganz explains, “Independent navigation through unfamiliar indoor spaces is beset with barriers for the visually impaired. A task that is trivial and spontaneous for the visioned population has to be planned and coordinated with other individuals for the visually impaired.”

Independent sight-impaired individuals typically receive training from an orientation and mobility instructor in order to accommodate themselves to buildings they need to visit regularly, but subway stations are much more complex spaces. Unlike an office building, a subway station has no general flow or layout. Moreover, the subway layout can change, depending on time of day. For example, gates open at rush hour are closed at other times. Escalators move up sometimes and then down at others.

Signage is usually placed out of sight from those with low-functioning vision. The high level of ambient noise in the underground atmosphere makes it harder for the visually impaired to use their sense of hearing and detect openings, follow the flow of traffic, and generally navigate through space. Indeed, as noted by the MBTA and the Massachusetts Commission for the Blind, no deployed technological solutions exist that provide accurate and affordable navigation instructions in subway systems.

 Not until now, that is.

As Ganz has written, “We will develop a prototype of an accurate and affordable navigation system for the visually impaired in subway stations. The prototype will be piloted in Arlington Metro Station of the MBTA and will be initially tested with visually impaired users as volunteers.”

The proposed system is innovative because it incorporates several new paradigms. First, it features “interactive spaces,” which relate to users in real time and accounts for their changing location throughout the station. Next, PERCEPT is operated by a gesture-based user interface on the smartphone that enables visually impaired users to interact with the space in the station. Finally, the system will offer detailed navigation instructions with safe navigation fundamentals.

When PERCEPT is in place at the Arlington Metro, NFC tags will be deployed at specific landmarks determined by an orientation and mobility instructor. Ganz cites the navigation experience of a hypothetical user, named Alice, to illustrate how PERCEPT will work in Arlington Station. Alice carries her smartphone that includes the IMS application. After choosing the destination (e.g. inbound), the IMS app will provide navigation instructions, either when the smartphone touches the NFC tag or when she swipes its screen for Next instructions.

Once Alice reaches the entrance to the station, she places her phone over the NFC tag located there. When the phone scans the tag, the app says: “Your current starting station is Arlington Main entrance, please proceed down the stairs along the right-side wall. When you get to the bottom of the stairs, scan the card on the wall to your immediate right, or swipe Next.”

Alice proceeds down the stairway and identifies the next NFC tag located at the bottom of the stairs. She places her phone over the tag, and the app says: “Turn left and follow your right-hand wall past the elevator until you reach the opening and then swipe Next for further instructions.”

After Alice identifies the opening, she swipes Next on her phone and the app says: “Continue to follow your right-hand wall into the opening. This is a long hallway that will lead into the main lobby. Swipe Next when reaching the end of the hall.” In this way, the navigation system will continue to direct Alice to her destination.

Before being put into use, the new navigations system will be thoroughly tested by a total of 10 visually-impaired subjects recruited by Carole Wilson, certified orientation and mobility specialist with more than 25 years of experience from the Massachusetts Commission for the Blind in Boston.

As Ganz observes, “PERCEPT can significantly alleviate the challenges introduced above.”

The PERCEPT system was developed with the cooperation of the Massachusetts Orientation and Mobility division of the Massachusetts Commission for the Blind using approximately $400,000 in funding from the National Institute of Health/National Eye Institute. (February 2014)