2001 Conference Proceedings

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ACCESSIBLE GPS NAVIGATION AND DIGITAL MAP INFORMATION FOR BLIND

Michael May
Davis, California
E-mail: MikeMay@SenderoGroup.com

As computers become smaller and faster, and with the vast improvements in voice input and output, revolutionary navigation devices for blind and other disabled individuals no longer need to be special high-priced, niche-market units. Accessible mainstream navigation technology represents the potential for a quantum leap in independence and social integration.

What are the traditional map and mobility tools for the blind?

When it comes to maps, blind people are not only in the dark, they are in the dark ages. While tactile maps are great for giving one an overview of a country, state or city, they are not suited for detailed street and landmark information. The fundamental size limitation of tactile resolution and the lack of other options have left blind people depending upon sighted people to describe map details.

The talking digital map, Atlas, provides blind people independent and equal access to maps. For the first time, blind people have as good as or better detailed street maps as sighted readers have on printed maps. It is possible to figure out a route and become familiar with the lengths of blocks and directions in the comfort and safety of one’s home or office. This is much easier than trying to figure out directions while also using a cane or dog on the street. Atlas provides access to millions of streets and addresses through the use of a talking street-map browser with a digital database. Orientation is an important task for blind people, and Atlas provides access to a very important part of orientation, information.

What comprises a talking GPS navigation system?

The Sendero Group combines a talking notebook or wearable computer, satellite signals and digital map data with special software to speak block-by-block orientation information to the user. Strider was the first iteration of this system, which was under development at Arkenstone from 1993 to 1999. The Sendero Group licensed this technology from Arkenstone in late 1999 and released their first products in March 2000.

What mainstream navigation products may be applicable for the blind?

The evolution of commercial GPS technology is key to our efforts. GPS is cheaper and smaller and the hardware pieces are more integrated. However, screen information is not accessible on GPS units, talking car units do not describe intersections and voice input systems are slow in responding and undependable in many environments.

Why haven’t GPS systems for the blind caught on?

Arkenstone put strider on hold in 1997 largely because the GPS hardware design was weak and expensive. The GPS industry itself was still immature. Commercial products were too large and costly. The lack of integrated components made the systems bulky and cumbersome.

What are some of the hurdles and the benefits of this technology?

Atlas has been on the market for 5 years and we have demonstrated it to hundreds of blind and sighted users. Everyone is very impressed when his or her own address appears on the screen and is spoken out loud. As they have explored using Atlas, users have discovered cross streets they never knew existed even in they’re own neighborhoods. Most blind users who purchased Atlas, have become avid proponents.

Massive map databases offer a tremendous amount of detailed information which could be challenging for a blind user who has traditionally only had limited street map information. When Atlas describes an intersection in terms of the compass, clock face or right-left-front-back, the user may not initially have the mental imaging skills to understand the intersection description. It takes practice hearing these descriptions before the user can automatically process the information. Atlas users learn this detailed map information in a non-threatening setting.

It is important that users have mental imaging skills when they use GPS-Talk in addition to Atlas. We don’t want the navigation information to interfere with mobility. GPS-Talk can be completely quiet other than announcing when it is time to turn or when the user asks it for information like, "which way is my destination?"

Most of us think of GPS navigation being used by accomplished travelers, it was Lukas Frank of the Seeing Eye who suggested that there might be a more crucial role for this technology in assisting the person who has no sense of direction. He used the phrase, "can’t find their way out of a paper bag." If the technology is simple and reliable enough, he may be correct.

Another aspect of GPS navigation for the blind, which has been under-played, is the use in vehicles. We live in an age of motor vehicles and although blind people may walk more than the average person, more than half their travel time is probably spent in a vehicle. When a blind person is in a vehicle, there is little to no contact with the signs and landmarks one is passing. We ride in a vehicular cocoon, deprived of information even more than when walking. There are no mobility safety issues either when listening to audible information in a car versus on foot. The blind user can be a navigator, a blind back-seat driver so to speak.

Also, GPS works better in a car than when on foot because the vehicle is in better view of the satellites in the street than a pedestrian is on the sidewalk, possibly blocked by buildings. It works well in a bus or train traveling in the relative open. For the first time in vehicles, a blind person has the choice of as much or as little information about their surroundings as they want with Sendero’s GPS-Talk.

Future Sendero Navigation Developments

One of the greatest weaknesses for GPS based navigation systems has been inside buildings and subways. We are working with several military oriented products to integrate a Dead Reckoning Module with GPS-Talk to enhance navigation in urban canyons and indoors. A technology called Snap Track allows weak GPS signals to be received inside buildings. The fact that mobile telephones must have an accurate "E911" location ability gives the incentive for commercial manufacturers to come up with good all-around location technology.

There are a couple of projects underway to utilize "Smart Phones" which are a combination mobile cellular telephone and GPS receiver. Some day we will be able to press "511" and ask an operator or automated attendant directions to the nearest pub.

If what one needs were to follow a simple route to the store, a basic talking waypoint box would do the job. This box could double as the GPS component of GPS-Talk so one would have the choice of which system to bring along, the Way-Talker unit or the complete GPS-Talk street navigation unit.

As the demand for low cost GPS integration increases, the pedestrian oriented products will begin to emerge. The challenge when we are on the cusp of a technology transition is that it is difficult to demonstrate demand for products, which don’t yet exist. It is the proverbial chicken and the egg, which face manufacturers and consumers of emerging navigation technologies. The mobility field and blind users have the opportunity to be at the leading edge of these developments; we have the chance to shape the technology rather than adapting it to our needs. Sure, there are lots of improvements, which can be made, and those improvements will be even more appropriate if we get Atlas and GPS-Talk into the hands of blind users and mobility instructors and integrate their feedback into future location information products.


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