SEAMLESS
OUTDOOR/INDOOR NAVIGATION FOR BLIND AND VISUALLY IMPAIRED INDIVIDUALS
Presenter #1
Michael May
Sendero Group LLC
Country; USA
Day Phone: 530—757—6600
Fax: 530—757—6830
Email: mikemay@senderogreup.com
Presenter #2
Charles LaPierre
Sendero Group LLC
1118
day Phone: 530—757—6800
Email: oharles@senderogroup.com
Sendero Group, pioneer of accessible Global
Positioning Systems (GPS) for outdoor navigation, explores the indoor
navigation frontier.
Complete Paper: The Global Positioning System (GPS) and related indoor
navigation technologies, combined with ever-growing location databases, present
the opportunity for those who cannot see signs to have an audible
representation of the environment. Hear about and see demonstrations of the BrailleNote GPS and state-of-the-art way finding
technologies like GPS cell phones and indoor navigation.
Outdoor Navigation Background
Over the past few years, the GPS commercial market has exploded. People are
using UPS in rental cars, on hiking trips, and in many other recreational
activities. Mapping companies have built massive databases with street names,
addresses, business names, points of interest, restaurants, underwater wrecks,
and the list goes on. Anything, which is stationary, is likely to be
electronically labeled.
With this boom in electronic data, blind people no longer need be limited to
the 1% location information to be glean from sighted people. The maps and
points of interest are o longer just a drawing on an inaccessible print map.
They are loaded on compact flash backards within portable Braille and speech
devices.
Accessible UPS for blind and visually impaired people has been developed based
upon the data and the latest GPS hardware. By combining the BrailleNote
PDA with the latest UPS Technology one has the ultimate tool for expanding and
exploring the environment while
able to switch at any time to the other BrailleNote
applications like the Internet, Email, Word Processor, MP3 player, Address
Book, Planner and more. Two other accessible GPS systems have emerged, Trekker
and StreeTalker for the Pac Nate. The blind traveler
can now be a co-pilot in a car, not just a passive passenger. I-Ic or she can keep the taxi river honest and can enjoy
hearing about the sites and businesses being passed while in a
ear, bus, or even on foot. There is nothing more empowering for a blind person
than getting around effectively and location information makes this possible.
GPS Accuracy
GPS receivers have on average 30 feet accuracy. So, instead of picturing CPS
position as a pinpoint, picture it as a bubble of radius 30 feet around your
position. If the GPS receiver is Wide Area Augmentation System (WAAS) enabled,
meaning that there are complimentary satellites and ground stations to correct
for some of the standard OHS error, the user can provide as good as 10 feet
accuracy.
Tall buildings or cliffs can obstruct OPS satellites, potentially degrading
accuracy. The latest receivers are sensitive enough to even pick up satellites
inside buildings but the accuracy and direction of travel are further degraded.
The limitations of GPS could translate into a situation where an individual has
arrived at the building for a job interview on time but spend 30 minutes trying
to navigate the hallways to find an office. Clearly, independent indoor
navigation is as important as accessible outdoor navigation.
Indoor Navigation Developments
For the last four years, Sendero Group has been
working with a Swiss company, Vectronix, which makes
high end compasses for military equipment. They have designed a navigation
module with various motion sensors that allow a person’s movement to be tracked
when wearing this device independent of OPS or other sensors. They have incorporated
OPS into this module and we have connected it to the BrailleNote.
We refer to this as the Personal Navigation Module, PNM. This type of technology is generically called
dead reckoning. One of the challenges with dead reckoning is that an error accumulates
over a distance, unlike OPS which has a fixed error. So, the PNM will
accumulate about 15% error, not so bid after lOb feetbut pretty bad, 150 feet error after walking a thousand
feet.
There are various ways to reduce this error by coupling the PNM with other
sensors and Vectronix is trying to reduce the error
as well in the core module. For one, the OHS can correct the error as soon as
you go outside. We put a command on the BrailleNote
that allows the user to correct the error manually when you are in a known
place like the entrance to a shop. If the PNM says you are 30 feet away from
the shop and you are in the doorway, you just press the Control 0 to zero out
the error. This means the next doorway is more likely to be where you expect
it.
Another option is to correct the error automatically using position sensors in
the environment like RFID tags, Talking Signs or even WiFi
points. There is a technology called Talking Lights whereby a florescent light
has its ballast changed so the light has a unique position ID. Sendero has teamed up with Talking Lights to test how this
combination of BrailleNote GPS, the PNM and Talking
Lights will work for indoor/outdoor navigation. A very early stage test was
conducted at Benetech in July. It worked reasonably
well most of the time and it showed us what needed improvement.
With the introduction of seamless indoor/outdoor navigation, it is possible to
achieve an environment which is totally accessible. One would he able to plan
out a street route to get to a destination. Once at the destination, one would
be able to walk down a hallway inside a building and hear the elevator
announced, or the heading and distance to the rest rooms.
Sendero Group is collaborating on indoor and outdoor wayfinding with 5 universities under 5—year NIDRR grant as
well as working with mainstream navigation companies. A prototype
of the indoor component is expected to be demonstrated at CSDN 2006 where the
first 10- pound accessible OHS system was shown by Sendero
in March 2000. The smallest accessible BrailleNote
OHS, 1-pound, will be demonstrated as well as accessible OHS on a cell phone.
The actual process of getting somewhere can now be fun and not a chore.
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