[Art_beyond_sight_educators] Maps, mapping

fnugg at online.no fnugg at online.no
Sun Sep 29 05:46:19 UTC 2013

Calgary company makes perfect pitch for top prize at tech showcase

Invici (pronounced 'en VEE cee') actually sprang from Hagedorn's work on 
his Master's Degree in Geography at the University of Calgary; he 
learned how difficult it was for some to use maps, and so he began to 
explore other ways to represent geographic features and information. 
Invici is an acronym for 'non-visual cartography'.

Now Hagedorn plans to change the lives of blind and visually impaired 
people with a multi-touch computer interface that lets them interact 
with on-screen information in totally new ways.


Mapping a room in a snap
  Blind people sometimes develop the amazing ability to perceive the 
contours of the room they're in based only on auditory information. Bats 
and dolphins use the same echolocation technique for navigating in their 
environment. At EPFL, a team from the Audiovisual Communications 
Laboratory (LCAV), under the direction of Professor Martin Vetterli, has 
developed a computer algorithm that can accomplish this from a sound 
that's picked up by four microphones. Their experiment is being 
published this week in the /Proceedings of the National Academy of 
Sciences/ (/PNAS/). "Our software can build a 3D map of a simple, convex 
room with a precision of a few millimeters," explains PhD student Ivan 

Randomly placed microphones

As incredible as it may seem, the microphones don't need to be carefully 
placed. "Each microphone picks up the direct sound from the source, as 
well as the echoes arriving from various walls," Dokmanic' continues. 
"The algorithm then compares the signal from each microphone. The 
infinitesimal lags that appear in the signals are used to calculate not 
only the distance between the microphones, but also the distance from 
each microphone to the walls and the sound source."


Echolocating app will let you map a room with sound

Bats, dolphins and even some blind people use echoes to create a mental 
3D map of their environment and where they are in it. A smartphone's 
chirp could soon let us do the same.

Ivan Dokmanic and colleagues at the Swiss Federal Institute of 
Technology (EPFL) in Lausanne have developed a system capable of 
reconstructing the shape of a room -- and where you are in it - using 

What's key to the trick, say human echolocators 
is sensing the strong early reflections off the walls, rather than the 
noisy, confusing mishmash of late-arriving, weaker echoes.

Hoping to computerise this process of 3D visualisation, the EPFL team 
has developed a system capable of reconstructing the shape of a room 
using these "first order" echoes. To do this, the researchers wrote an 
echo-sorting algorithm which can discriminate between the first and 
later echoes.

To test their plan they set up a loudspeaker and five microphones in 
Lausanne cathedral. The speaker briefly emitted an audible chirp - 
sweeping from 200 hertz to 10 kilohertz - and the reflections were 
analysed to successfully reveal the cathedral's 3D shape and the 
location of the sound source (/PNAS/, DOI: 10.1073/pnas.1221464110).

Computer algorithm uses echoes to create 'virtual' room maps

A new computer algorithm that can give humans the ability to map their 
environments with sound could lead to an app to aid blind people, Swiss 
researchers say.

Some animals such as bats, whales and dolphins use echolocation -- 
emitting a sound and listening to the echo -- to create a mental map of 
their environment, and some blind people have learned to use finger 
snaps or tongue clicks to create a rough equivalent, they said.

Read more: 


A New Echolocation Algorithm Can Map Spaces Based on Sound Alone 

How software works out room shape


Blind Maps: Braille Navigation System Concept
A couple of years ago we learned about Plan.B 
<http://technabob.com/blog/2010/11/02/plan-b-concept-map-for-the-blind/>, a 
concept for a map for blind people. The idea behind that system was 
sound, but I thought the execution left much to be desired. I like this 
other concept called Blind Maps 
<http://www.industrialdesignserved.com/gallery/Blind-Maps/2951161> much 
more. It's supposed to be a Bluetooth add-on for the iPhone that 
provides Braille-like turn-by-turn navigation.

Plan.B Concept: a Map for the Blind
I'm amazed every time I see blind people walking around on their own 
using only a cane to guide them. But what if there was also a way to 
make the sight-impaired "see" the surrounding geography? That's the idea 
behind Robert Richter's concept device, plan.b. Plan.b is a digital 
device that applies a simplified version of the Braille system, making 
tactile versions of maps.

Blind Maps

Autonomous Vehicle Technology Could Help Blind to Navigate


Blind Robot Gets Around

Biologists at LMU have demonstrated that people can acquire the capacity 
for echolocation 
although it does take time and work.

As blind people can testify, we humans can hear more than one might 
think. The blind learn to navigate using as guides the echoes of sounds 
they themselves make. This enables them to sense the locations of walls 
and corners, for instance: by tapping the ground with a stick or making 
clicking sounds with the tongue, and analyzing the echoes reflected from 
nearby surfaces, a blind person can map the relative positions of 
objects in the vicinity. LMU biologists led by Professor Lutz Wiegrebe 
of the Department of Neurobiology (Faculty of Biology) have now shown 
that sighted people can also learn to echolocate objects in space, as 
they report in the biology journal /Proceedings of the Royal Society B/.

Wiegrebe and his team have developed a method for training people in the 
art of echolocation. With the help of a headset consisting of a 
microphone and a pair of earphones, experimental subjects can generate 
patterns of echoes that simulate acoustic reflections in a virtual 
space: the participants emit vocal clicks, which are picked up by the 
microphone and passed to a processor that calculates the echoes of a 
virtual space within milliseconds. The resulting echoes are then played 
back through the earphones. The trick is that the transformation applied 
to the input depends on the subject's position in virtual space. So the 
subject can learn to associate the artificial "echoes" with the 
distribution of sound-reflecting surfaces in the simulated space.

*A dormant skill*

"After several weeks of training, the participants in the experiment 
were able to locate the sources of echoes pretty well. This shows that 
anyone can learn to analyze the echoes of acoustic signals to obtain 
information about the space around him. Sighted people have this ability 
too; they simply don't need to use it in everyday situations," says Lutz 
Wiegrebe. "Instead, the auditory system actively suppresses the 
perception of echoes, allowing us to focus on the primary acoustic 
signal, independently of how the space alters the signals on its way to 
the ears." This makes it easier to distinguish between different sound 
sources, allowing us to concentrate on what someone is saying to us, for 
example. The new study shows, however, that it is possible to 
functionally invert this suppression of echoes, and learn to use the 
information they contain for echolocation instead.

In the absence of visual information, we and most other mammals find 
navigation difficult. So it is not surprising that evolution has endowed 
many mammalian species with the ability to "read" reflected sound waves. 
Bats and toothed whales, which orient themselves in space primarily by 
means of acoustic signals, are the best known.


Smartphone-like device that maps surroundings to aid blind

A smartphone-like gadget that senses an entire room's features, builds a 
virtual map of it and communicates this to the user may one day replace 
the humble white cane to help blind sense their surroundings.

Using special multi-sensor array technology, the Indoor Navigation 
Project will enable blind to sense their surroundings beyond the cane's 
tip, researchers said.

Project leader Dr Iain Murray from the Curtin University said the gadget 
would resemble a smartphone and would sense an entire room's features, 
build a virtual map of it and communicate this to the user.


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