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Forum Proceedings

Stakeholder Forum on Technology for Vision Impairment

Wayfinding: Forum Data

The following information was collected during the T²RERC's Stakeholder Forum and reflects the comments and needs expressed by the Forum participants. The materials are not presented in order of importance.

Market Needs (unmet needs of people with blindness and low vision)

Market needs related to wayfinding are separated into three broad categories including global, local, and immediate.

Global Wayfinding needs span beyond the person's immediate environment. These needs include the ability for planning a route, identifying travel impediments and identifying the compass direction of travel. Global needs include the ability to:

obtain the information contained in printed maps;
determine the best route to travel to a destination related to traveling preferences (e.g., walking or taking the bus);
communicate directional information to a sighted person when lost or in emergency (e.g., current location, path to new location);
locate bus stops and subway stations.

Local Wayfinding needs include identification of the ambient environment as the traveler is en route. Local needs include the ability to:

obtain directions that incorporate orientation and mobility language (e.g., move forward 120 feet, turn left; move forward 50 feet, turn right);
identify dangerous obstacles along the route of travel (e.g., a construction detour);
determine what buildings are located in the immediate area (e.g., points of interest);
determine how individual locations within an area are directionally related to each other (e.g., the park is north and east of the library);
determine how far away a building is in relation to a starting point;
determine the address of the current location (e.g., 255 Main Street);
determine the type of building you are in (e.g., the bank, the library);
determine what is housed within the building (e.g., cafeteria, specific offices, restrooms);
locate important landmarks within a building (e.g., elevators, emergency exits, restrooms);
orient to and within a structure using cardinal directions (e.g., north, south, east, west);
know the information displayed on building windows (e.g., business hours, advertisements of sales);
access emergency information within a building (e.g., location of fire extinguishers and emergency exits);
find the way back to a seat on an airplane, in the movies or at a restaurant.

Immediate Wayfinding needs include obstacle avoidance in the immediate path of travel and locating specific architectural and environmental fixtures within physical reach of the individual. Immediate needs include the ability to:

identify and locate objects, including people, in the immediate vicinity;
follow a path (e.g., cross the street without veering, in a park);
identify, avoid, and/or navigate around hazards (e.g., ladder in front of elevator, tree limb across sidewalk);
identify and communicate non-visual landmarks (e.g., the noise and air movement from a fan, tactile changes from carpeting to granite flooring) for providing directions to others (e.g., to a friend who is looking for you);
access textual information within buildings (e.g., office directories, names and numbers of rooms).

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State-of-the-Practice (current technology, strengths, weaknesses, etc.)

GPS/GIS [Note: Global Positioning System (GPS) operates using a web of 24 satellites placed and maintained by the U.S. Department of Defense around the earth's orbit. These satellites transmit information to ground receivers placed on the earth's surface. These receivers utilize the satellite data to pinpoint the geographic location of the user's system (TechTarget 2003). Geographic Information System (GIS) is a data base of location information that is spatially referenced (United States Census Bureau, 2001). These systems allow for spatial information to be analyzed and displayed allowing for route planning and information gathering (Wyoming Geographic Information Science Center 2002)];
a bilingual talking compass. [Note: The bilingual talking compass is a hand held device that verbally announces eight major compass points including north, east, south, west, northeast, northwest, southeast and southwest. It announces the direction that the compass is pointing at the touch of a button and provides output using digitized speech in two languages, selected from a large list of most major languages (Robotron 2000)];
the Miniguide (miniaturized Mowat Sensor) [Note: The Miniguide is a mobility aid designed to provide information to a blind traveler which will supplement that provided by other aids such as the white cane and dog guide. There is both an audio and a tactile version in which sensors send and receive data (GDP Research, n.d.);
the Mowat Sensor is a lightweight, hand-held ultrasonic torch. It detects objects by sending out brief pulses of high frequency sound (ultrasound). Users can tell how close they are to an object by the rate of vibration produced by the Mowat Sensor. The device ignores everything but the closest object within the beam (Guide Dogs NSW/ACT 2003)];
white cane;
guide dog;
Sonic Cane / Sonic Guide [Note: The Sonic guide is an electronic travel aid that uses a downswept FM ultrasound signal to detect obstacles. A two-channel receiver picks up and converts the signal into a binaural audio signal (The Eye of the Pacific Guide Dogs and Mobility Services 2003)];
Laser Cane [Note: The Laser Cane produces three beams of laser light. Reflected rays are detected to identify objects in the user's path. The Laser Cane generates three auditory tones and a vibration for high, low and mid-height objects. Sweeping the cane provides 3-dimensional information about the user's surroundings (Nurion-Raycal, 2000)];
Braille labels (providing navigation cues);
guided tours, or more generally, asking assistance from another person;
environmental cues (e.g., edged tiles);
Audio tours (e.g., voice recorded information systems that direct the visitor through an exhibit or a museum in a linear fashion. Variations include systems where the visitor meanders to exhibits of choice and presses a selection button to have related information spoken);
Czechoslovakian "Talking Box" – distributed navigation system. [Note: The Talking Box uses a transmitter to activate beacons located on or around public facilities, including buildings, and public transportation systems. In order to use the system, the person with a visual impairment carries either a small 6 button transmitter or a system is mounted on a standard white cane. The beacons provide auditory tones or verbal information about the surrounding environment. The system is required on all new buildings and on reconstructed buildings across the Czech Republic creating a city-wide orientation system to assist in wayfinding (Allen-King & Wilkens, 2002)];
Netherlands "Talking Box" – distributed navigation system. [Note: refers to the "Easy Walker System," in which a hand-held, infrared receiver uses beacons that are installed in strategic places within a building. The user chooses the desired destination (e.g., restroom, exits) by using a keypad on the receiver. Verbal directions to that location are then provided through the receiver. (Royal National Institute of the Blind, 2002)];
Monocular [Note: Monocular telescopes, available in a variety of magnification strengths, are used for distance viewing of street signs, grocery store aisle signs, bus signs, etc. (Corn & Koenig, 1996)];
Audible, automated stop calling system [Note: In order to comply with accessibility measures outlined by the ADA, this system is an automated system used to announce location information to passengers, including stops, train/bus information, etc. (Talking Bus®, 2003)];
Talking Lights™ [Note: The Talking LightsTM utilizes specialized fluorescent light ballasts to encode information in the emitted fluorescent light. A portable receiver decodes this information and provides it to the user (Talking Lights, 2003)];
iButton [Note: An iButton allows a user to carry digital information or wireless functions to open doors, access funds for payment (much like the Mobile Speedpass). The iButton is small enough to place on a keychain, ring, or watch (Waloszek, 2002)];
Talking Signs® [Note: Talking Signs® receivers decode infrared signals from transmitters located in the environment (e.g., street, library). Each receiver has a distinct audio message. Receivers provide navigational information. The user sweeps the receiver until its signal strength is maximized (pointing at a nearby transmitter). Talking Signs receivers work robustly in daylight (with the exception of pointing the receiver toward the sun). WiFi networked transmitters are available in the most recent version (Talking Signs 2001)];
audible signs / audio pedestrian signals (chirping) [Note: Accessible or audible pedestrian signals provide information in non-visual format, which includes audible tones or verbal messages, and/or vibro-tactile information. Birdcalls (cuckoo and chirp) are sometimes used to indicate which crosswalk currently has a walk interval (Bentzen 1998)];
Talking Tactile Maps [Note: Talking Tactile Maps provide texture, raised lines and audio to allow persons with visual impairments access to map information. Audio information is accessed by touching tactile regions. This system can provide important route information in both interior and exterior environments (Landau 1999)];
public transportation voice recorded information / audio transportation announcements [Note: The ADA mandates that public transportation systems provide accessible information for people with disabilities. For people who are blind or visually impaired, this means that all print information will be presented in either large print, tactile or audio formats (American Foundation for the Blind 1998).]

Global Positioning Systems /Global Information Systems

Note: GPS and GIS are distinct but synergistic technologies. Roughly, GPS wirelessly triangulates a location of a receiver on earth, while GIS is a database(s) populated with information about that location. GPS and GIS are distinct but complimentary technologies.

The strengths of GPS include:

GPS signal is available "anywhere;"
requires no infrastructure modifications;
available to anyone with a receiver;
portable receivers.

The strengths of GIS (on a GPS system) include:

provides location dependent information;
able to locate points of interest;
describes points of interest;
identifies an intersection;
gives distance to destination;
gives recommended path to destination;
provides information on the local environment (e.g., addresses, businesses, streets);
user can add information about points of interest and landmarks;
user can add wayfinding points (i.e., analogous to laying trail markers that can be followed later);
no monthly fee incurred by using GPS/GIS system;
mainstream technology (e.g., car navigations systems) - production volume keeps the cost down.

The weaknesses of GPS include:

does not work well indoors (e.g., building infrastructure interferes with satellite signal);
performance degrades in bad weather (interferes with satellite signals);
satellite signals can be blocked (e.g., mountains, buildings, trees) in which case, receiver cannot triangulate position.
commercial GPS is currently accurate within 3 to 10 meters. Not a basis to avoid immediate obstacles when walking. [Note: Military GPS is more accurate. Technology called Differential GPS employs additional satellite signals to improve positional resolution. DGPS also helps alleviate the signal blocking problem. DGPS is very accurate and is now available on high end commercial systems (Trimble Navigation Limited, 2003).]
does not provide the user with point directionality (e.g., cannot tell the user the direction they are facing);
receiver has to be carried by the user;
cannot tell the user which side of the street he is on.

The weaknesses of GIS (on a GPS system) include:

GIS databases are not updated frequently (e.g., location based information goes out of date);
GIS databases are often specialized (e.g., local plants, streets and businesses, historical landmarks) [See Trimble http://www.trimble.com/bp_mgis_az.html];
GIS database must be installed on the receiver;
does not include local and daily information (e.g., today's menu, news or safety warnings, etc);
significant cost to develop GIS databases;
must purchase GIS databases;
GIS data sets are focused on the information needs of sighted consumers - much of the information needed by blind consumers is lacking;
GIS databases focus on roads, buildings and "civilization" rather than parks and wilderness;
sometimes hard to interpret information;
sometimes provides too much information.

Talking Signs

The strengths of Talking Signs include:

can interface with and provide real-time information from other message technologies (e.g., can be programmed to receive information from the variable display signs at a bus station to make the information related to the next bus arrival accessible);
can be used to obtain directional information (signal strength is maximized when receiver is pointed at transmitter);
easily expandable (arbitrary number of transmitters can be added);
flexible in the information they provide;
easily reprogrammed to adapt to the changing environment [Note: A new version has RF receivers and can be accessed through a wireless WiFi network, programmable from a single computer];
relatively inexpensive (e.g., receivers in some areas are provided for free or with a small deposit, transmitter for a store or business costs approximately $385, sometimes money from city is available for merchants to offset the cost);
the infrastructure for use is in place (e.g., the technology is developed, it works, and systems are in place to expand and improve it, and there is a industry to support it.)
can be easily installed by a business;
unobtrusive (e.g., the transmitter for businesses is a box that can be installed in the window and plugged into a standard wall socket);
doesn't require a lot of training to use the receiver;
very intuitive (e.g., for orientation purposes, as you scan the receiver, the message is fuzzy. As you orient to and approach the source, the message gets clearer. As you go past the source, the message gets fuzzy again);
facilitates greater independence;
can be used with headphones to provide a level of privacy.

The weaknesses of Talking Signs include:

receiver requires a lot of battery power to run outdoors;
has limited range (especially in daylight);
each transmitter must be individually installed;
the signal can be cut off (even by glass);
transmitters are not located everywhere;
sound is disconnected from its source (e.g., the sound comes from the receiver in your hand, not from the destination. Does not support "normal" hearing-based orientation.);
the user must carry a receiver;
the receiver is too big;
the user must scan/look for the Talking Signs (e.g., this can sometimes draw unwanted attention to the user);
message is not always understandable (e.g., poorly recorded, degraded signal).

Audible Pedestrian Signals

The strengths of Audible Pedestrian Signals include:

have a variety of audible sounds, some also provide information using speech and / or tactile output and / or vibrating feedback;
provides a beacon that makes it easier to cross streets;
reduces the need for traveler to pay close attention to the sounds of moving traffic.

The weaknesses of Audible Pedestrian Signals include:

cause noise pollution;
have an annoying noise;
have an ambiguous signal (e.g., the sounds are not universal);
some birds mimic sounds used by pedestrian signals (e.g., distracts or misleads the traveler);
high pitched frequencies used for audible signal are not easily located in space (e.g., low frequency signals are easier to localize);
costly to retrofit signals.
provide the user with specific location information that they did not know;
show spatial relationships;
reinforce spatial learning;
provide a concrete image of the surroundings;
are fairly detailed;
provide access to individuals who are deaf/blind;
are portable (e.g., although depending on their size and the material they are made of, they can be awkward to carry around);
can be inexpensive (e.g., if small and simple);
can be modified (e.g., labels and other tactile cues can be added for individual use);
can be reproduced (e.g., multiple copies of the same map can be made).

The weaknesses of Tactile Maps include:

are not readily available;
require a learned skill to interpret them;
require a lot of preparation time to make;
require a lot of skill to make;
difficult to pack detailed information onto map;
can be expensive to design (e.g., if large and complex);
susceptible to damage (e.g., paper Braille susceptible to weather damage and tearing, thermoform maps and or plastic are more durable);
are not dynamic so they won't represent recent changes.

Talking Tactile Maps

The strengths of Talking Tactile Maps include:

provide a good overview of the local setting;
has the potential to identify all necessary landmarks;
the programmed information is provided by orientation and mobility experts so it is understandable;
are self-identifying so they are easy to find (e.g., motion detector activates a message is identifying map location);
can provide lots of detailed information in audio recording;
easy to use (e.g., raised line map mounted on a touch sensitive computer pad, provides audio information by pressing down, or use a keypad if you don't want to touch the graphic);
when available, persons with visual impairments don't have to rely on strangers for information.

The weaknesses of Talking Tactile Maps include:

are not available in many locations;
do not assist in getting to a specific location (does not provide path guidance);
are not portable;
can only be used by one person at a time;
kids like to play with them (e.g., sometimes monopolize the use so a person with a visual impairment does not get the chance to use it);
require skill in interpreting the tactile graphics;
requires an expert to complete the programming;
tactile graphics cannot be dynamically updated (e.g., , only the audio information can be easily changed - not the physical map).

Public Transportation Voice Recorded (PTVR) Information

The strengths of PTVR include:

provides information in unfamiliar surroundings;
provides information on which bus you are entering and where it is going;
presents the same information that is available on printed signs;
assists everyone, not just those who are visually impaired;
does not require the user to carry extra equipment with them;
is usually loud and clear;
is easily installable in existing vehicles;
if it breaks down, human assistance can take over.

The weaknesses of PTVR include:

is limited to pre-recorded announcements;
sometimes the information provided is insufficient;
does not announce all stops;
information is often incorrect (e.g., not properly updated);
you cannot always hear it;
causes noise pollution;
is an accommodation that cannot be refused (e.g., you receive information even when you do not want or need it);
breaks down frequently.

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Unmet Needs (Identification of important consumer needs that are poorly met by technology that has been introduced or discussed to this point).

General needs that are unmet by current wayfinding tools include:

ability to determine the best route to travel to a destination that reflects the preferences and needs of the traveler;
ability to determine the best means of transportation (e.g., walking, taxi, bus, subway) to reach a destination;
improved GPS/GIS-like functionality;
ability to identify obstacles and re-plan routes (e.g., a detour past a construction site);
ability to obtain changing environmental information (e.g., new sidewalks, driveways, buildings);
ability to orient to a structure (point of interest) using cardinal directions;
ability to orient within a structure (point of interest) using cardinal directions;
need to know the configuration of an intersection;
ability to gauge proximity (nearness, distance) of buildings of interest;
ability to construct a path (through a city);
ability to navigate free space (through a park, in the wilderness);
ability to follow a path (feedback on deviation from path);
need a technology to provide spatial cognition training for specific wayfinding needs.

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Technology Solutions

From the list of unmet needs above, two areas were discussed in detail in an attempt to identify the functions and characteristics of the technology that would best meet these needs.

The Obstacle Avoidance Device

(defined as a device that can obtain constant updates of changing environmental information).

Need Areas:

identify obstacles, both overhead and below;
discern the nature of obstacles (e.g., sharp, soft, thin);
identify inaccessible terrain at a distance corresponding to a street width (able to discern problems before crossing a street);
identify extreme changes in elevation, a block away;
identify rapidly approaching vehicles;
identify the direction of the obstacle (e.g., left/right/up/down);
inform the user when traffic lights are not working;
identify the cardinal direction the user is pointing to;
detect the indentation of doorways;
provide navigation information inside buildings and outdoors;
provide peripheral information (e.g., what lies to both sides);
provide output in tactile, speech, audio and Braille formats;
be user customizable (e.g., specify the distance at which obstacles are identified, set how often the feedback is provided);
have the capacity to calculate a pedestrian route;
provide an alternate route once an obstacle is identified [Note: perhaps integrated with GPS/GIS capabilities];
accesses (and utilizes) regional and community obstacle information (e.g., road construction, building construction blocking walkways) in route planning (and otherwise);
operate on a battery that lasts at least one day;
be small and lightweight (e.g., the size of a cell phone, pager, or PDA);
interface with other technology, preferably through a wireless connection (e.g., cell phone capabilities, WiFi, BlueTooth) [Note: this capability would allow devices to access and integrate local and perhaps rapidly changing information, download GIS data sets or transmit information about the local environment to others];
accept video camera input [Note: with cell phone capabilities, this would support transmission of video information to a remote sighted person to ask for description of local environment);
employ smart universal interface supporting integration with 1) GPS, 2) ultrasonic systems, 3) Talking Signs, and 4) laser canes;
work in all lighting conditions [Note: more generally, wayfinding technology should work across all environmental conditions likely to be encountered];
be waterproof;
work indoors and outdoors;
not be affected by color, only grayscale, black & white;
provide location specific information (e.g., room name, room description, today's menu etc);
incorporate all these features and be enclosed within one device.

Travel route and transportation device

(defined as a device that can determine the best travel route and means of transportation to a destination including user preferences and predefined criteria).

Need Areas:

be used as travel planning tool;
calculate the travel time;
calculate the travel distance;
identify the expense of the transportation mode (e.g., bus, train, cab fare);
be programmable to the user's interest and skill level (e.g., "simple," "fast," "short," or "cheap");
tap into the airline schedules, bus schedules and modes, and train schedules;
generate the e-ticket;
have local information (about streets, buildings, construction, traffic, etc.) that can be integrated into planning for the route;
have a "know as you go" feature (e.g., where am I now, what is immediately about me, how far do I have to go, what direction am I going, etc.);
be customizable (e.g., allows user to determine the level of details related to the travel route and the transportation mode);
have an emergency backup telephone internet connection;
have GPS capabilities;
have updatable GIS capabilities;
be the size of a cell phone or smaller;
be intuitive to use;
fail gracefully (e.g., infrequent crashes, sure recovery from crashes, quick restart from crashes);
tell you when it is not working [Note: notification must be in accessible format];
have voice input (for control), voice output and a tactile, large print touchpad interface;
be backwards compatible [Note: Must be able to work well with current systems (Bos, 2003.);
use standard interfaces (e.g., USB ports, WiFi) supporting communication with a wide range of input/output devices including laptops and tactile displays;
employ a wireless interface (e.g., WiFi, BlueTooth);
be built into existing technology, like a cell phone;
be developed by a reliable company who will maintain the databases (reflecting needs of persons with vision impairments).

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Barriers

What barriers will hinder the development and introduction of these ideal products?

Obstacle Avoidance Device

the required processing power is too large;
it will be expensive to develop;
it will be difficult to convey the amount of information required in an understandable way;
pattern recognition technology has not been developed yet;
not enough consumer field testing.

Travel Route and Transportation Device

will require a great deal of programming to develop and maintain the database;
may be difficult to use;
the required GIS information doesn't exist on a global level.

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Resources

What resources will facilitate the development and introduction of the ideal product?

Travel Route and Transportation Device

GPS, ultrasound and laser systems are already out there;
GIS provides multiple layers of information, and that capability can be exploited;
various state, local, and possibly federal agencies with the technologies they have (e.g., Department of Transportation);
Talking Signs as well as Talking Lights and anything that is going to be put into the environment;
Stanford Center for Design Research;
The Defense Mapping Agency (DMA).

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References

Allen-King, J. & Wilkens, P. (2002). Independent mobility for blind people: Moving forward the Czech way. Retrieved June 17, 2003, from http://www.euroblind.org/fichiersGB/czech.htm
American Foundation for the Blind. (1998). Factsheet: Accessible mass transit. Retrieved June 24, 2003, from http://www.afb.org/info_document_view.asp?documentid=907
Bentzen, B. L. (1998). Accessible pedestrian signals. Retrieved August 27, 2003, from http://www.access-board.gov/research&training/pedsignals/pedestrian.htm
Bos, B. (2003). Backwards compatibility. Retrieved January 30, 2004, from http://www.w3.org/People/Bos/DesignGuide/compatibility.html
Corn, A.L., & Koenig, A.J. (1996) Foundations of low vision: Clinical and functional perspectives, NY, NY: ABF Press.
GDP Research. (n.d). The Miniguide ultrasonic mobility aid. Retrieved June 17, 2003, from http://www.gdp-research.com.au/ultra.htm
Guide Dogs. (2003). Electronic mobility devices. Retrieved June 17, 2003, from http://www.guidedogs.com.au/services/electron_mobility_devices.htm
Landau, S. (1999). Tactile graphics and strategies for non-visual seeing. Thresholds 19, pp. 78 – 82. MIT School of Architecture. Retrieved June 17, 2003, from http://www.touchgraphics.com/thresholds.htm
Nurion-Raycal. (2000). The new Lasercane TM N-2000. Retrieved January 7, 2003, from http://www.nurion.net/lasercane.htm
Robotron. (2000). Columbus talking compass. Retrieved August 27, 2003, from http://www.robotron.net.au/columbus.htm
Royal National Institute of the Blind. (2002). Personal electronic mobility devices. The Easy Walker system. Retrieved August 27, 2003, from http://www.tiresias.org/equipment/eb23.htm
Talking Bus. (2003). The DR500C+ Talking Bus system. Retrieved June 24, 2003, from http://www.talkingbus.com/products/dr500c/dr500c_moreinfo.html
Talking Lights. (2003). How we do it. Retrieved June 17, 2003, from http://www.talking-lights.com/how.htm
Talking Signs. (2001). How talking signs work. Retrieved June 17, 2003, from http://www.talkingsigns.com
TechTarget. (2003). Global positioning system. Retrieved June 17, 2003, from http://searchnetworking.techtarget.com/sDefinition/0,,sid7_gci213986,00.html
The Eye of the Pacific Guide Dogs and Mobility Services (2003). The laser cane. Retrieved June 17, 2003, from http://eyeofthepacific.org/prod02.htm
Trimble Navigation Limited (2003). Why do we need differential GPS? Retrieved January 7, 2004, from http://www.trimble.com/gps/whydgps.html
United States Census Bureau, 2001. The GIS FAQ. Retrieved January 7, 2004, from http://www.census.gov/geo/www/faq-index.html
Waloszek, G. (2002) Changing the world, changing ourselves. Retrieved June 24, 2003, from http://www.sapdesignguild.org/community/readers/print_reader_chi2002_gw.html
Wyoming Geographic Information Science Center (2002). Definitions: GSI. Retrieved June 17, 2003, from http://www.wygisc.uwyo.edu/gis.html

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