CASTalk.com

"Wieslaw Bicz" <W.Bicz@optel.pl> schrieb im Newsbeitrag
news:41B85BA4.3030501@optel.pl...

fragil technology with higher resolution and lower costs.

After I have read this post, I have had the idea, that I would be able to
propose a novel idea for this purpose, that may be very attractive,
because this allows to makes devices with even large surfaces, that can
produce even large pictures. This idea is based on may

Yes, I guess it would be possible to apply a core technology similar to
displaying TV pictures line by line.

experience, and

this is the reason, whyI think, that this will work, but it requires some
money for the development.

You are right, and this is probably the problem why such technology is not
further developed or even sold.

The device will not contain any moving

elements.

Sure not, the three things I see as obstacles is

a) To find a suitable surface material
b) to find components which are able to switch a high voltage on and off
with high frequency and deflect it.
c) Do extensive testing to see if the approach as such works as we think it
might word.

If somebody is interested in it, I would be able to do this development
and create a product. This can be surely patented.

But I simply don't see a big market for such product since even my old
machine is no longer made.
/Roland

"Jim Douglas" <james.douglas@genesis-software.com> wrote:

Check out the medical device called a "Tens" unit, it's send a small
tingle.

The first part of the problem is to find a set of nerves on/in the body
which can be used to "see". The fingertips are sensitive, but very small.

I would try the skin on one of my thighs, it is fairly easy to attach a
thin elastic cloth around it and leave it on all day.

Then I need a way to excite the nerves in the skin of my thigh.

200*300 points, or more, on the inside of the cloth will excite the
nerves and create a picture which wraps around my thigh, and I use the
nerves in the skin to "see" it.

The idea about electrostimulation fits well into this device.
I would simply try different combinations of frequencies and currents
until I found a setting which gave the best "image" without being painful
in any way.
Mechanical stimulation is also possible, but would be a little more
difficult to manufacture.

A small videocamera can be hidden below or above my own face, in a
band around my head, like a tennis player's sweatband, for example.

So I would feel with my thigh what the camera sees.

With some training it could become really useful.



--
Roger J.

I read in sci.electronics.design that Roger Johansson <no-email@home.se>
wrote (in <Xns95BBC317B4A5786336@130.133.1.4>) about 'Circuit that
produces a tingling sensation in the fingers.', on Fri, 10 Dec 2004:

I would try the skin on one of my thighs, it is fairly easy to attach a
thin elastic cloth around it and leave it on all day.

Then I need a way to excite the nerves in the skin of my thigh.

IIRC, you have picked the body area where nerves in the skin are most
sparse.
--
Regards, John Woodgate, OOO - Own Opinions Only.
The good news is that nothing is compulsory.
The bad news is that everything is prohibited.
http://www.jmwa.demon.co.uk Also see http://www.isce.org.uk

John Woodgate <jmw@jmwa.demon.contraspam.yuk> wrote:

I would try the skin on one of my thighs, it is fairly easy to attach a
thin elastic cloth around it and leave it on all day.

Then I need a way to excite the nerves in the skin of my thigh.

IIRC, you have picked the body area where nerves in the skin are most
sparse.

That may be so but the number of receptors is big enough.
Touch the thigh anywhere very lightly and you
will feel it and you can tell exactly where it is touching.

I thought about the back of the body first, because it is big area, but
it would need some kind of adhesive and very flexible surface to stay in
contact with every piece of skin. An elastic cloth around the thigh stays
in contact with every piece of skin under it.

To make a prototype I would try to find a very thin and flexible wire,
which I could fix in the cloth, by sewing into the fabric. At the end of
the wire I would take off the isolation for a few millimeters and make a
loop or knot which does not irritate the skin mechanically.
(copper wire may irritate the skin, so I would get some other surface
metal on the wire, or chemically add a layer of zink or whatever works
better against the skin than copper)

Then I need a microprocessor which can be programmed to take the average
of the light level in one small area of the video picture and send a
signal of that level to the skin. Maybe 4*4 pixels for each skin
stimulation point. (Because the number of pixels in the camera will
probably be much higher than the number of pixels in my thigh cloth.)

We need controls for intensity and contrast for the skin. They will work
just like the intensity and contrast control on a tv. I might want to
adjust these controls during the day, and when I sleep I turn down to
black screen, or take of the cloth.



--
Roger J.

On Fri, 10 Dec 2004 17:38:43 +0100, Roland Zitzke wrote:

"Robert Monsen" <rcsurname@comcast.net> schrieb im Newsbeitrag
news:eSHtd.628892$mD.13594@attbi_s02...
Roland Zitzke wrote:
I am using such device for 25 years now myself and as an engineer I am
constantly looking for techniques to replace / rebuilt it.


Roland, is this a device to help you see? I've read about these, but never
actually had any direct contact. Can you recognize different faces? Or the
fact that a face is in front of you?

Yes, I use it because I am blind and it lets me recognize images when moving
a CCD camera over it.

As mentioned the represented image is quite small (20 x 5) and this is not
enough for recognizing complex structures like a face in the sence that I
could tell two faces apart.
Biometry is a science of it's own ;-)

With a device I suggested it could be a much larger image and that would
certainly enable "TV for the blind" to some degree.

I seem to remember seeing a thing on edjamacayshunal TV where somebody
actually put electrodes against some volunteer's brain, at the back, at
the visual cortex. The lobes all have names, but all I can remember of
them is Steve Allen pointing at a skull, saying, "This is the frontal,
this is the top-al, this is the back-al, and these are the two sides-al."

Occipital?

But I don't think you're ready to have electrodes poked into your brain,
are you? =:-O

On a less goofy note, I do wonder how hard it would be to build a bigger
array of little piezo thingies. Probably not all that hard, just big bucks. )-;

Good Luck!
Rich

On Fri, 10 Dec 2004 17:50:08 +0100, Roland Zitzke wrote:

But I simply don't see a big market for such product since even my old
machine is no longer made.
/Roland

I hope I'm not being impertinent, but how do you read newsgroups? With
your device we're talking about, or do you have talking software?

Thanks,
Rich

On Fri, 10 Dec 2004 18:15:29 +0000, Roger Johansson wrote:

"Jim Douglas" <james.douglas@genesis-software.com> wrote:

Check out the medical device called a "Tens" unit, it's send a small
tingle.

The first part of the problem is to find a set of nerves on/in the body
which can be used to "see". The fingertips are sensitive, but very small.

I would try the skin on one of my thighs, it is fairly easy to attach a
thin elastic cloth around it and leave it on all day.

Then I need a way to excite the nerves in the skin of my thigh.

200*300 points, or more, on the inside of the cloth will excite the
nerves and create a picture which wraps around my thigh, and I use the
nerves in the skin to "see" it.

The idea about electrostimulation fits well into this device.
I would simply try different combinations of frequencies and currents
until I found a setting which gave the best "image" without being painful
in any way.
Mechanical stimulation is also possible, but would be a little more
difficult to manufacture.

A small videocamera can be hidden below or above my own face, in a
band around my head, like a tennis player's sweatband, for example.

So I would feel with my thigh what the camera sees.

With some training it could become really useful.

Put the device _in_ the sweatband, and feel it on your forehead.
For my second choice, I'd go chest or back. But as Mr. Woodgate has
mentioned, the thigh is probably one of the least sensitive pieces of skin
that you have. Then again, this might simplify the design.

Y'know, this could turn out to be an interesting project!

But I still say that applying electric shocks doesn't sound like the best
way to do things.

Hey! How about some of those microphonic/piezoelectric SMT caps? ;-)

Good Luck!
Rich

Rich Grise <rich@example.net> wrote:

Put the device _in_ the sweatband, and feel it on your forehead.

That is a good idea too, and it would simplify the wiring as the camera
and the skin area are so close. The whole device could be integrated in
the head band. But I wonder if it would be better for feeling where
things are in the picture.

For my second choice, I'd go chest or back. But as Mr. Woodgate has
mentioned, the thigh is probably one of the least sensitive pieces of
skin that you have. Then again, this might simplify the design.

Y'know, this could turn out to be an interesting project!

But I still say that applying electric shocks doesn't sound like the
best way to do things.

I am not talking about painful levels, just a tingling sensation.

Hey! How about some of those microphonic/piezoelectric SMT caps? ;-)

You mean for translation from electrical signals to mechanical?

The beepers in pocket computers are like a piece of tape, thin adhesive
piezoelectric material. It can produce a mechanical movement controlled
by electrical signals. Yes, it could work too.


--
Roger J.

I read in sci.electronics.design that Rich Grise <rich@example.net>
wrote (in <pan.2004.12.10.19.16.31.64580@example.net>) about 'Circuit
that produces a tingling sensation in the fingers.', on Fri, 10 Dec
2004:

I hope I'm not being impertinent, but how do you read newsgroups? With
your device we're talking about, or do you have talking software?

The Royal National Institute for the Blind in UK has done an enormous
amount of work on computer aids for blind people. Quite a few years ago,
they has voice-operated writers (needed a lot of training, so not viable
commercially) and readers. The readers would run at speeds far higher
than normal speech and people were trained to understand at those
speeds.
--
Regards, John Woodgate, OOO - Own Opinions Only.
The good news is that nothing is compulsory.
The bad news is that everything is prohibited.
http://www.jmwa.demon.co.uk Also see http://www.isce.org.uk

On Fri, 10 Dec 2004 20:31:18 +0000, the renowned John Woodgate
<jmw@jmwa.demon.contraspam.yuk> wrote:

I read in sci.electronics.design that Rich Grise <rich@example.net
wrote (in <pan.2004.12.10.19.16.31.64580@example.net>) about 'Circuit
that produces a tingling sensation in the fingers.', on Fri, 10 Dec
2004:
I hope I'm not being impertinent, but how do you read newsgroups? With
your device we're talking about, or do you have talking software?

The Royal National Institute for the Blind in UK has done an enormous
amount of work on computer aids for blind people. Quite a few years ago,
they has voice-operated writers (needed a lot of training, so not viable
commercially) and readers. The readers would run at speeds far higher
than normal speech and people were trained to understand at those
speeds.

The human brain can interpret speech at a much higher speed than
people can speak clearly. There are devices that speed up voice
(essentially by stealing chunks of it, so that it doesn't increase in
pitch) and they are still understandable at much higher than normal
speeds. I wonder if there's a better algorithm that might be practical
today.


Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
speff@interlog.com Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog Info for designers: http://www.speff.com

Roland Zitzke wrote:

Since the late 1970s there were devices available called Optacons.
snip
Unfortunatly this technology has disappeared from the market. It
essencially
consists of a neadle array (20 x 5) where such trigger is stimmulated
by
vibrating certain sets of these pins at a time.

Roland,

Would you please describe the spacing of the pins as best you can --
or (the overall dimensions of the rectangle? I
have an idea that might reproduce this device's behavior, and be
somewhat scaled up.

Similarly, do you know anything about the
frequency of vibration used? (If memory serves, one peak in human
sensitivity to vibration is around 300 Hz., and I *think* there's
another one (different sensory neurons?) much lower (50 Hz?.)
Unfortunately the neurologist who I recall mentioning the frequency
response is no longer here to ask.

Do you think a quasi-static displacements would work well enough to
use? Fast enough to show sequences of tactile "images" (like a
morph-able wood carving), but not fast enough to feel like a vibration?
In that case, an array of pins displaced by resistance-heated Nitinol
wires might work for a dense, potentially inexpensive device.
Larry Pfeffer

Roland Zitzke wrote:

Since the late 1970s there were devices available called Optacons.
snip
Unfortunatly this technology has disappeared from the market. It
essencially
consists of a neadle array (20 x 5) where such trigger is stimmulated
by
vibrating certain sets of these pins at a time.

Roland,

Would you please describe the spacing of the pins as best you can --
or (the overall dimensions of the rectangle? I
have an idea that might reproduce this device's behavior, and be
somewhat scaled up.

Similarly, do you know anything about the
frequency of vibration used? (If memory serves, one peak in human
sensitivity to vibration is around 300 Hz., and I *think* there's
another one (different sensory neurons?) much lower (50 Hz?.)
Unfortunately the neurologist who I recall mentioning the frequency
response is no longer here to ask.

Do you think a quasi-static displacements would work well enough to
use? Fast enough to show sequences of tactile "images" (like a
morph-able wood carving), but not fast enough to feel like a vibration?
In that case, an array of pins displaced by resistance-heated Nitinol
wires might work for a dense, potentially inexpensive device.
Larry Pfeffer

In comp.arch.embedded Rich Grise <rich@example.net> wrote:

But I still say that applying electric shocks doesn't sound like the best
way to do things.

Seconded. Keeping in mind that our nerves themselves are operating
based on electricity, I suspect that the basic rule of thumb is:
there's no such thing as safe electrostimulation of sensory nerves.
Your stimulus can either be too weak for anything to be registered at
all, or too strong to be safe.

The margin between these two thresholds on stimulus strength is
probably too small to be safe for everyday usage other than in a
*very* closely controlled environment (say, within shouting distance
of an ICU, with trained medical personnel controlling the apparatus,
given a rather specific medical indication for doing it).

--
Hans-Bernhard Broeker (broeker@physik.rwth-aachen.de)
Even if all the snow were burnt, ashes would remain.

In message <41b6f241$1_1@news.ecore.net>, Roland Zitzke
<FODVRUTMSTJC@spammotel.com> writes

"Denis Gleeson" <dgleeson-2@utvinternet.com> schrieb im Newsbeitrag
news:184c35f9.0412040855.6a4a25df@posting.google.com...
the possibility of allowing the identification of items through a
persons sense of touch.


Since the late 1970s there were devices available called Optacons.
http://www.nfbae.ca/publications/index.php?id=375

Unfortunatly this technology has disappeared from the market. It essencially
consists of a neadle array (20 x 5) where such trigger is stimmulated by
vibrating certain sets of these pins at a time.
This in fact allows detailed pattern recognition without the effect of
distress on the finger.
I am using such device for 25 years now myself and as an engineer I am
constantly looking for techniques to replace / rebuilt it.

<Snip>

I wonder if single line of (say) 16 small needles with 16 photodiodes
(or whatever) controlling them would work? Rather than move your finger
across a fixed array of pins, you have the line of pin/sensors fixed to
your finger and move the line across the object.

Some years ago I tried the electrical stimulation technique but found it
impossible to set a useable frequency/voltage/current. Only small
changes in pressure or moistness varied the stimulus between
undetectable and painful.

Cheers
--
Keith Wootten

Regarding safety:

Keith Wootten wrote:

Some years ago I tried the electrical stimulation technique but found
it
impossible to set a useable frequency/voltage/current. Only small
changes in pressure or moistness varied the stimulus between
undetectable and painful.

and Hans-Bernhard Broeker wrote:

I suspect that the basic rule of thumb is:
there's no such thing as safe electrostimulation of sensory nerves.
Your stimulus can either be too weak for anything to be registered at
all, or too strong to be safe.

Neural stimulation can be done safely, though special care is certainly
indicated -- as is keeping well away from the heart, unless you're an
EMT or a cardiologist!

In the U.S. there are devices approved by the FDA, for use (including
home use) for treating chronic pain. Googling
TENS neural stimulation will produce many hits on such. An earlier
poster alluded to 5 mA, and this is in the range mentioned in several
biomedical Eng. texts. That's a rough ballpark, though it doesn't take
into account electrode area, and thus current density. It does,
however, point toward a key aspect of doing this reasonably safety --
controlling the current, very important, given the wide variations in
resistance.

Interested readers may wish to read a related thread on
sci.electronics.design,
thread title "Bipolar current source for muscle stimulations"
(started 23Oct2004.) This thread includes a schematic for delivering a
controlled (bipolar) current, submitted by the estimable Winfield Hill.
-- Larry Pfeffer
(larry underscore pfeffer at verizon dot com)