From: Sha Xin Wei
Date:07/21/2014 7:34 AM (GMT-07:00)
To: Hannah Perner-Wilson , "Byron Lahey (Student)" , Assegid Kidane , Adrian Freed
Cc: Chris Wood , Xin Wei Sha , Xin Wei Sha , Navid Navab , Oana Suteu , Pavla Baxová
Subject: [QI4Q] making paper sensors
Hi all,
For the past few months some Chris Wood and I have been working with colleagues on 'Q is for Quicken', a project to create a multi-modal book that responds to touch by creating sound. We'd like to ask your advice on a few of the finer points of the design pertaining to paper and electronics.
At this stage, the 'book' is in fact a series of loose leaf sheets inside a box containing electronics embedded in its base. We need a system to detect when the reader has arrived at one of several sheets spread throughout the stack. Our current thinking is to embed photocells inside paper bookmarks in between the sheets we need to identify. (The sheets will be opaque.) That way when the reader lifts a sheet off of a page that should trigger sound when exposed, the intervening bookmark’s photocell will signal the box’s circuitry thru its tether.
However, we'd be grateful for any more elegant suggestions you have. As much as possible, we want to avoid the pages being tethered to the box.
Also, we would like the cover of the box to display the words 'Q is for Quicken' when it's placed in the light. We are wondering if there's a way of doing this reliably with photochromic or thermochromic material.
At present we are using a force sensitive resistor to detect touch. This is giving us a good range of analog values, but we are wondering if there is a simple way to achieve greater quality of motion information. We are currently using a teensy 3.1 microcontroller with the newly developed audio shield, but we are not tied to this technology.
Many thanks for any thoughts or comments you have.
All the best,
Xin Wei + Chris
Date:07/21/2014 7:34 AM (GMT-07:00)
To: Hannah Perner-Wilson , "Byron Lahey (Student)" , Assegid Kidane , Adrian Freed
Cc: Chris Wood , Xin Wei Sha , Xin Wei Sha , Navid Navab , Oana Suteu , Pavla Baxová
Subject: [QI4Q] making paper sensors
Hi all,
For the past few months some Chris Wood and I have been working with colleagues on 'Q is for Quicken', a project to create a multi-modal book that responds to touch by creating sound. We'd like to ask your advice on a few of the finer points of the design pertaining to paper and electronics.
At this stage, the 'book' is in fact a series of loose leaf sheets inside a box containing electronics embedded in its base. We need a system to detect when the reader has arrived at one of several sheets spread throughout the stack. Our current thinking is to embed photocells inside paper bookmarks in between the sheets we need to identify. (The sheets will be opaque.) That way when the reader lifts a sheet off of a page that should trigger sound when exposed, the intervening bookmark’s photocell will signal the box’s circuitry thru its tether.
However, we'd be grateful for any more elegant suggestions you have. As much as possible, we want to avoid the pages being tethered to the box.
Also, we would like the cover of the box to display the words 'Q is for Quicken' when it's placed in the light. We are wondering if there's a way of doing this reliably with photochromic or thermochromic material.
At present we are using a force sensitive resistor to detect touch. This is giving us a good range of analog values, but we are wondering if there is a simple way to achieve greater quality of motion information. We are currently using a teensy 3.1 microcontroller with the newly developed audio shield, but we are not tied to this technology.
Many thanks for any thoughts or comments you have.
All the best,
Xin Wei + Chris
On Jul 21, 2014, at 8:52 AM, Assegid Kidane <[email protected]> wrote:
What concerns me with the bookmark idea is that you will need as many tethered bookmarks as pages that need to be detected. This may be ok with some wire routing tricks if the fairly precise alignment of paper and bookmark can be tolerated during each page removal and placement.
Is there a reason for moving away from the resistor network solution we employed on the box we made on Tempe? If it does not seem to work reliably, it may be because it may need one last calibration programming due to possible resistance changes after the conductive glue of the conductive fabrics have settled and died. Connectivity between each pages can also be further improved by adding an esthetically suitable weight on the top page such as a 2*11*1/4" metal block. We could also add a spring loaded flap that needs to be lifted before a page is removed.
The challenge with activating the thermochromic material is producing the temperature change neatly. Most built-in electrical solutions will be very power hungry as it will involve a heater. One other solution we have not discussed before is using a Peltier unit. External temperature control options include heat guns and heat lamps.
Best Regards,
Assegid Kidané
From Mobile
What concerns me with the bookmark idea is that you will need as many tethered bookmarks as pages that need to be detected. This may be ok with some wire routing tricks if the fairly precise alignment of paper and bookmark can be tolerated during each page removal and placement.
Is there a reason for moving away from the resistor network solution we employed on the box we made on Tempe? If it does not seem to work reliably, it may be because it may need one last calibration programming due to possible resistance changes after the conductive glue of the conductive fabrics have settled and died. Connectivity between each pages can also be further improved by adding an esthetically suitable weight on the top page such as a 2*11*1/4" metal block. We could also add a spring loaded flap that needs to be lifted before a page is removed.
The challenge with activating the thermochromic material is producing the temperature change neatly. Most built-in electrical solutions will be very power hungry as it will involve a heater. One other solution we have not discussed before is using a Peltier unit. External temperature control options include heat guns and heat lamps.
Best Regards,
Assegid Kidané
From Mobile
On Jul 21, 2014, at 5:03 PM, Adrian Freed <[email protected]> wrote:
Have you consulted these experts on the question?
https://www.crowdsupply.com/chibitronics/circuit-stickers
http://www.nataliefreed.com/tide-book/
http://p-dpa.tumblr.com/post/51138143764/telescrapbook-natalie-freed-jie-qi-adam
From what I can tell of your plans it seems that Ji and Natalie already did what you are trying to do wirelessly.
I would experiment with near field RFI stickers too.
The teensy has free, built-in capacitance sensing and you can easily introduce modulated capacitance into
paper books with the carbon and silver ink pens that are now easy to find (e.g. bare conductive).
Have you consulted these experts on the question?
https://www.crowdsupply.com/chibitronics/circuit-stickers
http://www.nataliefreed.com/tide-book/
http://p-dpa.tumblr.com/post/51138143764/telescrapbook-natalie-freed-jie-qi-adam
From what I can tell of your plans it seems that Ji and Natalie already did what you are trying to do wirelessly.
I would experiment with near field RFI stickers too.
The teensy has free, built-in capacitance sensing and you can easily introduce modulated capacitance into
paper books with the carbon and silver ink pens that are now easy to find (e.g. bare conductive).
I haven't used magnetic ink. It may be harder to find now that checks are optically scanned.
Note that the Teensy 3++ (no ship date announced yet) will have a floating point ARM and higher
clock rate. This will make
it easy to port DSP from PD etc. Under $30.
On Jul 22, 2014, at 4:35 PM, Todd Ingalls <[email protected]> wrote:
i think that was what i showed you:(
just throwing this out - what about hall effect sensors in bottom of the box and magnetic ink?
ps - if you get more involved on the sound end i have been working on my own library for the teensy audio shield...
On Jul 22, 2014, at 4:22 AM, Sha Xin Wei <[email protected]> wrote:
Hi Todd,
Todd, hey do you have a solution for wirelessly detecting when a specific page has been exposed as a reader goes from sheet to sheet in a stack of paper sheets? I recall that you showed me what looked like the Chibitronics notebook… Is there a sticker that comes with a wireless sensor?
Adrian said that :
The teensy has free, built-in capacitance sensing and you can easily introduce modulated capacitance into
paper books with the carbon and silver ink pens that are now easy to find (e.g. bare conductive).
We need someone who can program the Teensy’s onboard sensor to detect based on capacitance then, and test whether it can sense through a wooden false bottom (0.4 cm thickness), and up to 4 separate sheets inserted into 26 sheets of paper.
Cheers,
Xin Wei
Note that the Teensy 3++ (no ship date announced yet) will have a floating point ARM and higher
clock rate. This will make
it easy to port DSP from PD etc. Under $30.
On Jul 22, 2014, at 4:35 PM, Todd Ingalls <[email protected]> wrote:
i think that was what i showed you:(
just throwing this out - what about hall effect sensors in bottom of the box and magnetic ink?
ps - if you get more involved on the sound end i have been working on my own library for the teensy audio shield...
On Jul 22, 2014, at 4:22 AM, Sha Xin Wei <[email protected]> wrote:
Hi Todd,
Todd, hey do you have a solution for wirelessly detecting when a specific page has been exposed as a reader goes from sheet to sheet in a stack of paper sheets? I recall that you showed me what looked like the Chibitronics notebook… Is there a sticker that comes with a wireless sensor?
Adrian said that :
The teensy has free, built-in capacitance sensing and you can easily introduce modulated capacitance into
paper books with the carbon and silver ink pens that are now easy to find (e.g. bare conductive).
We need someone who can program the Teensy’s onboard sensor to detect based on capacitance then, and test whether it can sense through a wooden false bottom (0.4 cm thickness), and up to 4 separate sheets inserted into 26 sheets of paper.
Cheers,
Xin Wei
On Jul 23, 2014, at 9:45 AM, Adrian Freed <[email protected]> wrote:
I haven't tried it but I suspect conductive inks might work instead of metallic plates, but copper tape is the rapid
prototyping for this. Calibration is definitely the challenge with
capacitive sensing. You can use the simple trick of calibrating w.r.t to a dedicated electrode attached to a page that is glued in place.
Then as the dielectrics change with temperature and humidity you have a local reference to measure against.
On Jul 24, 2014, at 2:59 PM, Byron Lahey <[email protected]> wrote:
I was thinking about capacitive sensing as well (considering that paper is the dielectric for many capacitors). The other thing I was contemplating was a variation on an optical sensing approach. You said that the paper sheets would be opaque. If they could be somewhat translucent then an IR LED could be paired with a photocell, or a an IR phototransistor (one above and one below the stack), so that as each sheet was removed the measured light level would increase. Need to see how IR (or other light spectrums) transmit through the paper. Do we have any paper samples?
This document looks interesting:
http://www.sofia.usra.edu/Edu/materials/activeAstronomy/section2.pdf
This one is even more interesting (especially since I'm about to get on an airplane back to Phoenix):
http://omicsgroup.org/journals/near-infrared-transmission-through-various-clothing-fabrics-2165-8064.1000129.pdf
A key idea here is the potential utility of modulating the source light signal at a fixed frequency to differentiate noise from low level signals.
The cover "secret message" system is not something I have any immediate ideas how to tackle. If the revealing light source was always the same it might be possible to do something with polarization filters and a polarized light source. If the light source can just be sensed with standard electronics then thermochromic ink seems like an option (sounds like Assegid has more ideas about this).
This is cool (not what we need, but inspiring):
http://www.carnovsky.com/RGB.htm
These folks would probably have good ideas:
http://www.rit.edu/cos/colorscience/
I'll keep thinking about this, and we can do some experiments when I get back tomorrow.
Best,
Byron
I was thinking about capacitive sensing as well (considering that paper is the dielectric for many capacitors). The other thing I was contemplating was a variation on an optical sensing approach. You said that the paper sheets would be opaque. If they could be somewhat translucent then an IR LED could be paired with a photocell, or a an IR phototransistor (one above and one below the stack), so that as each sheet was removed the measured light level would increase. Need to see how IR (or other light spectrums) transmit through the paper. Do we have any paper samples?
This document looks interesting:
http://www.sofia.usra.edu/Edu/materials/activeAstronomy/section2.pdf
This one is even more interesting (especially since I'm about to get on an airplane back to Phoenix):
http://omicsgroup.org/journals/near-infrared-transmission-through-various-clothing-fabrics-2165-8064.1000129.pdf
A key idea here is the potential utility of modulating the source light signal at a fixed frequency to differentiate noise from low level signals.
The cover "secret message" system is not something I have any immediate ideas how to tackle. If the revealing light source was always the same it might be possible to do something with polarization filters and a polarized light source. If the light source can just be sensed with standard electronics then thermochromic ink seems like an option (sounds like Assegid has more ideas about this).
This is cool (not what we need, but inspiring):
http://www.carnovsky.com/RGB.htm
These folks would probably have good ideas:
http://www.rit.edu/cos/colorscience/
I'll keep thinking about this, and we can do some experiments when I get back tomorrow.
Best,
Byron
On Jul 24, 2014, at 3:54 PM, Assegid Kidane <[email protected]> wrote:
The omicsgroup paper is interesting. Xin Wei, is it ok to add a swing away ir emitter above the page stack? It might even be possible to modify the box we already made by adding a filter since we already have a photo sensor installed.
The omicsgroup paper is interesting. Xin Wei, is it ok to add a swing away ir emitter above the page stack? It might even be possible to modify the box we already made by adding a filter since we already have a photo sensor installed.
On Jul 24, 2014, at 10:15 PM, Sha Xin Wei <[email protected]> wrote:
I prefer the embedded passive conductor for a capacitance sensing solution based in the bottom. No tethers. However, I fear we will not find an expert (in papers and active materials like Hannah or Jess) in time who can work shoulder to shoulder with Chris at CIID to fabricate solutions embedded inside the paper-substrate in time to carry this out. So maybe we can settle for more robust tethered solutions like photocell inside a paper bookmark.
I’ve decide on playing with the physical mockup that the sheets must give at least 4-6cm for the fingers to get underneath and pick up each sheet. So the sheets will slide in at least one dimension. (We can keep one dimension of the sheets = inside height of the box.)
Photos coming!
Ideally no electronic devices should appear outside paper. Ideally no PCB’s or electronic parts should be visible.
And, ideally I would like to use minimum (or zero) digital microprocessors and only analog electrical processing, powered by incident light, or mechanical oscillation. The sounding paper project is part of a sea-change in media arts that I hope to help instigate, away from its current sole reliance on digital computation, but in a more
I prefer the embedded passive conductor for a capacitance sensing solution based in the bottom. No tethers. However, I fear we will not find an expert (in papers and active materials like Hannah or Jess) in time who can work shoulder to shoulder with Chris at CIID to fabricate solutions embedded inside the paper-substrate in time to carry this out. So maybe we can settle for more robust tethered solutions like photocell inside a paper bookmark.
I’ve decide on playing with the physical mockup that the sheets must give at least 4-6cm for the fingers to get underneath and pick up each sheet. So the sheets will slide in at least one dimension. (We can keep one dimension of the sheets = inside height of the box.)
Photos coming!
Ideally no electronic devices should appear outside paper. Ideally no PCB’s or electronic parts should be visible.
And, ideally I would like to use minimum (or zero) digital microprocessors and only analog electrical processing, powered by incident light, or mechanical oscillation. The sounding paper project is part of a sea-change in media arts that I hope to help instigate, away from its current sole reliance on digital computation, but in a more
On Sat, Jul 26, 2014 at 2:18 PM, Adrian Freed <[email protected]> wrote:
It is actually easier to go analog with this particular set of requirements if you have the necessary analog engineering skills. Alas these aren't taught so much any more.
Might I suggest Syuzi's birdie brooch project as an entry point for people to look at this? http://books.google.com/books?id=xVVvKVQSSR8C&pg=PA107&lpg=PA107&dq=syuzi+pakhchyan+birdie+brooch&source=bl&
It can be powered with an organic solar cell.
Don't be confused by the use of so called "digital" chips in a lot of these low power sound generators. They are hybrid designs which can't be analyzed with the usual digital simplifications. You can find related designs in various early 4000 series CMOS theremins and capacitive touch patents from the 1950's through the 1970's, i.e. until the point the personal computer "revolution" turned us into button pushers.
It is actually easier to go analog with this particular set of requirements if you have the necessary analog engineering skills. Alas these aren't taught so much any more.
Might I suggest Syuzi's birdie brooch project as an entry point for people to look at this? http://books.google.com/books?id=xVVvKVQSSR8C&pg=PA107&lpg=PA107&dq=syuzi+pakhchyan+birdie+brooch&source=bl&
It can be powered with an organic solar cell.
Don't be confused by the use of so called "digital" chips in a lot of these low power sound generators. They are hybrid designs which can't be analyzed with the usual digital simplifications. You can find related designs in various early 4000 series CMOS theremins and capacitive touch patents from the 1950's through the 1970's, i.e. until the point the personal computer "revolution" turned us into button pushers.
On Sun, Jul 27, 2014 at 9:10 PM, Natalie Freed <[email protected]> wrote:
Hello!
A few ideas:
-Thin magnets embedded in the pages in a different location for each
page + hall effect sensors in the bottom of the box (We used this for
Telescrapbook and another project, works well with a bound book).
-I think Byron's IR idea is super interesting. Perhaps the light
source could be inside one of the walls of the box, pointed at an
angle through the pages.
-Something like those Hallmark recordable books which have holes in
each page near the spine and a column of photocells in the back cover.
-For the hidden writing in the cover, you could mill out the wood from
behind, leaving a thinner layer where the words are, so that turning
on lights behind the cover would show the text. Eg:
http://fab.cba.mit.edu/classes/MIT/863.10/people/matt.blackshaw/final.html
-Here's a link to some thermochromic paint documentation from Hannah's
site, though I can't find an actual tutorial at the moment:
http://www.flickriver.com/photos/plusea/sets/72157625772237628/
(scroll down to bottom-ish). It uses the technique of sewing
(stainless steel? something heat-resistant) conductive thread in a
pattern (eg. words) behind a thermochromic-painted surface, then
running enough current through the thread to heat it and reveal the
thread's pattern.
Also, is there a specific reason these are separate pages in a box
rather than a bound book? A bound book would be helpful with registration with the sensors.
Hello!
A few ideas:
-Thin magnets embedded in the pages in a different location for each
page + hall effect sensors in the bottom of the box (We used this for
Telescrapbook and another project, works well with a bound book).
-I think Byron's IR idea is super interesting. Perhaps the light
source could be inside one of the walls of the box, pointed at an
angle through the pages.
-Something like those Hallmark recordable books which have holes in
each page near the spine and a column of photocells in the back cover.
-For the hidden writing in the cover, you could mill out the wood from
behind, leaving a thinner layer where the words are, so that turning
on lights behind the cover would show the text. Eg:
http://fab.cba.mit.edu/classes/MIT/863.10/people/matt.blackshaw/final.html
-Here's a link to some thermochromic paint documentation from Hannah's
site, though I can't find an actual tutorial at the moment:
http://www.flickriver.com/photos/plusea/sets/72157625772237628/
(scroll down to bottom-ish). It uses the technique of sewing
(stainless steel? something heat-resistant) conductive thread in a
pattern (eg. words) behind a thermochromic-painted surface, then
running enough current through the thread to heat it and reveal the
thread's pattern.
Also, is there a specific reason these are separate pages in a box
rather than a bound book? A bound book would be helpful with registration with the sensors.
On Sun, Jul 27, 2014 at 9:25 PM, Natalie Freed <[email protected]> wrote:
Remembered one more project relevant to appearing/disappearing text:
http://fluid.media.mit.edu/projects/remnant
I don't know how it works but it's a rather lovely effect!
Remembered one more project relevant to appearing/disappearing text:
http://fluid.media.mit.edu/projects/remnant
I don't know how it works but it's a rather lovely effect!
From: Byron Lahey
Date: 07/27/2014 10:12 PM (GMT-07:00)
Nice ideas and examples Natalie. The same effect as the milled wood could be accomplished with layers of translucent and opaque materials laminated together. This could all be paper with an electroluminescent panel embedded in the layers.
The handwriting one was interesting. It seems to be illuminating a general area rather than the line of writing exactly.
I have a clear sense of the feel and aesthetic that you are trying to achieve Xin Wei. Achieving that elegant quality and having it be responsive and reversible is a significant challenge.
Date: 07/27/2014 10:12 PM (GMT-07:00)
Nice ideas and examples Natalie. The same effect as the milled wood could be accomplished with layers of translucent and opaque materials laminated together. This could all be paper with an electroluminescent panel embedded in the layers.
The handwriting one was interesting. It seems to be illuminating a general area rather than the line of writing exactly.
I have a clear sense of the feel and aesthetic that you are trying to achieve Xin Wei. Achieving that elegant quality and having it be responsive and reversible is a significant challenge.
On Jul 27, 2014, at 11:29 PM, Assegid Kidane <[email protected]> wrote:
With the box we made already using the elastolite display, all we need to do is add a mask layer to generate the text message our even graphics, and then a second thin translucent cover layer that covers the whole face. This top layer need to be opaque enough to not show the pattern when the display is off and thin enough to show the text when lit. One can use any number of materials from an arts or crafts store or could even be as simple as paper. If the message needs to be larger we can use 2 or more Elastolite panels. In fact, for testing on the box we made, one can place a layer of standard 8.5x11" sheet paper with the message pattern cut out and then a second layer on top and activate the light and see.
I wired the teensy for capacitive sensing and as expected it worked well with Copper foil when touched. Now, to make this useful for our application, the reading can only be taken at the moment of page placement since it is the capacitance through the human body ground that we are measuring. If we can obtain repeatable, consistently changing values with changing paper stacks irrespective of slite side to side paper movements, we may be able to use this. I will do further tests to verify this.
I am also exploring the possibility of employing inductive sensing.
With the box we made already using the elastolite display, all we need to do is add a mask layer to generate the text message our even graphics, and then a second thin translucent cover layer that covers the whole face. This top layer need to be opaque enough to not show the pattern when the display is off and thin enough to show the text when lit. One can use any number of materials from an arts or crafts store or could even be as simple as paper. If the message needs to be larger we can use 2 or more Elastolite panels. In fact, for testing on the box we made, one can place a layer of standard 8.5x11" sheet paper with the message pattern cut out and then a second layer on top and activate the light and see.
I wired the teensy for capacitive sensing and as expected it worked well with Copper foil when touched. Now, to make this useful for our application, the reading can only be taken at the moment of page placement since it is the capacitance through the human body ground that we are measuring. If we can obtain repeatable, consistently changing values with changing paper stacks irrespective of slite side to side paper movements, we may be able to use this. I will do further tests to verify this.
I am also exploring the possibility of employing inductive sensing.
On Jul 28, 2014, at 5:50 PM, Adrian Freed <[email protected]> wrote:
If you make your own paper you can do this by back illuminating a water mark.
This would eliminate the eventual phosphorous pollution of the elastolite.
On Jul 30, 2014, at 3:32 AM, Adrian Freed <[email protected]> wrote:
You may need some structured interdigitation with grounds to get this sort of thing to work. You use the conductors on the paper (I would
try some conductive ink)to capacitively shunt the interdigitation on the sensor base. Note that you can tweak the parameters of the very flexible teensy 3.1 cap sense to be more sensitive. Paul set them by default for classical reasonably fast, robust touch sensing. You have to dive into the source code to find them
On Jul 30, 2014, at 3:35 AM, Adrian Freed <[email protected]> wrote:
Very conductive ink is now available: https://123d.circuits.io/shop/circuitscribe
If you make your own paper you can do this by back illuminating a water mark.
This would eliminate the eventual phosphorous pollution of the elastolite.
On Jul 30, 2014, at 3:32 AM, Adrian Freed <[email protected]> wrote:
You may need some structured interdigitation with grounds to get this sort of thing to work. You use the conductors on the paper (I would
try some conductive ink)to capacitively shunt the interdigitation on the sensor base. Note that you can tweak the parameters of the very flexible teensy 3.1 cap sense to be more sensitive. Paul set them by default for classical reasonably fast, robust touch sensing. You have to dive into the source code to find them
On Jul 30, 2014, at 3:35 AM, Adrian Freed <[email protected]> wrote:
Very conductive ink is now available: https://123d.circuits.io/shop/circuitscribe
On Jul 30, 2014, at 4:43 AM, Sha Xin Wei <[email protected]> wrote:
Chris Wood and his supervisor, Andrew McPherson from EE @ Queen Mary will test an inductive solution with a coil printed with conductive pattern on the paper here in Copenhagen. Early tests are promising on the scope. They’re building a prototype detector circuit into the current Teensy-based circuit today.
It is useful to detect when a _particular_ sheet of paper is being lifted away or being dropped back down so we can use the continuous gradient info.
Chris, we may want to duplicate orders of parts so we can make two copies of the Artist Proof. Perhaps I could fly back to the States with one copy and the second copy could be your follow-up between Aug 15 and when you return to London? For future reference it’d be smart to have one copy in each continent. (Should I specify UK as its own continent, and suggest a anglophonic bias?)
Chris and I do not have direct experience with conductive ink so thanks Adrian for the reference to very conductive ink: https://123d.circuits.io/shop/circuitscribe. Our current plan is to print a conductive ink pattern onto paper in Queen Mary University London and express mail it to Copenhagen. Quicken project (Xin Wei ;) will pay for associate costs. (Thanks Andrew for this suggestion :)
Chris Wood and his supervisor, Andrew McPherson from EE @ Queen Mary will test an inductive solution with a coil printed with conductive pattern on the paper here in Copenhagen. Early tests are promising on the scope. They’re building a prototype detector circuit into the current Teensy-based circuit today.
It is useful to detect when a _particular_ sheet of paper is being lifted away or being dropped back down so we can use the continuous gradient info.
Chris, we may want to duplicate orders of parts so we can make two copies of the Artist Proof. Perhaps I could fly back to the States with one copy and the second copy could be your follow-up between Aug 15 and when you return to London? For future reference it’d be smart to have one copy in each continent. (Should I specify UK as its own continent, and suggest a anglophonic bias?)
Chris and I do not have direct experience with conductive ink so thanks Adrian for the reference to very conductive ink: https://123d.circuits.io/shop/circuitscribe. Our current plan is to print a conductive ink pattern onto paper in Queen Mary University London and express mail it to Copenhagen. Quicken project (Xin Wei ;) will pay for associate costs. (Thanks Andrew for this suggestion :)
On Jul 31, 2014, at 4:53 AM, Adrian Freed <[email protected]> wrote:
We prototype these sorts of things first by using my cutter/plotter on aluminum foil or thin copper film. If you have conductive printing down that is a great asset. We have also built prototypes by sewing conductive thread coils onto Yupo, paper, card stock and of course textiles.
I am not sure what people mean by inductive in this thread. If you are going so far as to be doing the sort of things that are in rfid tags,
why not just use the rfid stickers that you can easily buy?http://www.samsung.com/us/microsite/tectile/
We prototype these sorts of things first by using my cutter/plotter on aluminum foil or thin copper film. If you have conductive printing down that is a great asset. We have also built prototypes by sewing conductive thread coils onto Yupo, paper, card stock and of course textiles.
I am not sure what people mean by inductive in this thread. If you are going so far as to be doing the sort of things that are in rfid tags,
why not just use the rfid stickers that you can easily buy?http://www.samsung.com/us/microsite/tectile/
On Jul 31, 2014, at 4:04 AM, Andrew McPherson <[email protected]> wrote:
The idea with inductive sensing is basically to make a simple transformer using the paper: print two coils in different locations on the paper, electrically connected together. Then in the base of the box there is a transmitter coil being driven by a medium-frequency signal (say in the range 50-200kHz) and a receiver coil, spaced far enough apart that they don't strongly couple to each other. When the paper is in the box, the signal from the transmitter is coupled through the paper back to the receiver. As the paper is gradually removed, the signal at the receiver drops in amplitude.
It should be possible to sense multiple sheets of paper by having multiple transmitter coils and one receiver. Each transmitter is in a different place and sends a different frequency. Bandpass filters pull out each frequency at the receiver (and eliminate other hum and RF pickup). Each piece of paper has a different conductive pattern that aligns with one of the transmitter coils. (In fact, this could be scaled up with M transmitters and N receivers to have M*N independent sensors.)
We've got a simple proof of concept working. We also thought about RFID tags as an alternative which may end up being simpler; we didn't have any readers on hand so couldn't test it. But one potential advantage of the paper-transformer arrangement is that you get a continuous change as the paper is removed rather than detect/no-detect output. It'll take some more experimentation to see how robust it is.
The idea with inductive sensing is basically to make a simple transformer using the paper: print two coils in different locations on the paper, electrically connected together. Then in the base of the box there is a transmitter coil being driven by a medium-frequency signal (say in the range 50-200kHz) and a receiver coil, spaced far enough apart that they don't strongly couple to each other. When the paper is in the box, the signal from the transmitter is coupled through the paper back to the receiver. As the paper is gradually removed, the signal at the receiver drops in amplitude.
It should be possible to sense multiple sheets of paper by having multiple transmitter coils and one receiver. Each transmitter is in a different place and sends a different frequency. Bandpass filters pull out each frequency at the receiver (and eliminate other hum and RF pickup). Each piece of paper has a different conductive pattern that aligns with one of the transmitter coils. (In fact, this could be scaled up with M transmitters and N receivers to have M*N independent sensors.)
We've got a simple proof of concept working. We also thought about RFID tags as an alternative which may end up being simpler; we didn't have any readers on hand so couldn't test it. But one potential advantage of the paper-transformer arrangement is that you get a continuous change as the paper is removed rather than detect/no-detect output. It'll take some more experimentation to see how robust it is.
On Jul 31, 2014, at 5:11 PM, Adrian Freed <[email protected]> wrote:
THanks for the clarification. This is similar to the approach developed by Max Mathews and Bob Boie (inventor of capacitive touch screens) in the Radio Drum.
The suggestion I made early for using conductors in the paper to shape the fringing fields has a lot in common with the inductive scheme
when you take into account the particular way the Teensy microcontroller hardware does "capacitive" sensing: it puts what is connected to its input into the tuned circuit of an oscillator and measures frequencies.
The advantage of building your own oscillators is that you can increase the power and use frequency multiplexing. The Teensy approach uses low power and time and space multiplexing (via the 12 pins available). In the long run a comparison of these various approaches would make a great paper to publish.
THanks for the clarification. This is similar to the approach developed by Max Mathews and Bob Boie (inventor of capacitive touch screens) in the Radio Drum.
The suggestion I made early for using conductors in the paper to shape the fringing fields has a lot in common with the inductive scheme
when you take into account the particular way the Teensy microcontroller hardware does "capacitive" sensing: it puts what is connected to its input into the tuned circuit of an oscillator and measures frequencies.
The advantage of building your own oscillators is that you can increase the power and use frequency multiplexing. The Teensy approach uses low power and time and space multiplexing (via the 12 pins available). In the long run a comparison of these various approaches would make a great paper to publish.
On Aug 3, 2014, at 6:11 AM, Adrian Freed <[email protected]> wrote:
Adrian, thanks for is a remarkably spot-on reference :http://cache.freescale.com/files/sensors/doc/app_note/AN1985.pdf .
I’m trying to sift through the passages near Fig. 3 to determine whether interdigitated (zigzag) pattern indeed could work as well as spiral pattern, for the printing of patterns on paper in Queen Mary. It makes a difference because then we could lay out the pattern as a border, whereas a spiral would have to be integrated differently into the page layout design. (I’m looking for a graphic designer to consult on the page layout.)
The spirals for inductive coils are tricky because you have to find a way for the center to cross the coils and head off somewhere else.
I am proud of my solution to this in the project with Jess Rowland where we replaced spirals with iterations of nearly closed C shapes. I don't know how
to make this design work at RF frequencies though. It might work but I am not equipped with the specialty tools...
PS. I notice that Table 2. Dielectric Materials with Different Thicknesses and Dielectric Constants
does not include paper among its materials tested. So there was room for a contribution to the state of the art in 1985 :)
Dielectric properties of paper have been heavily studied as it is popular dielectric material in transformers and capacitors:
http://news.3m.com/press-release/company/new-insulating-paper-3m-combines-dielectric-performance-and-durability.
Paper hasn't been used much in capacitive multitouch scenarios because of the horrible things skin-born materials do to regular organic paper.
The closest commercial devices to this sort of thing I can thing of are the polyamide smart cards used in the Montreal Metro (or SF Bart).
Topologies for conductors on paper: https://embodied.mpi-inf.mpg.de/files/2012/11/ACuttableMultiTouchSensor.pdf
(Note the capacitances in table 1)
https://www.kickstarter.com/projects/1597902824/agic-print-printing-circuit-boards-with-home-print
Adrian, thanks for is a remarkably spot-on reference :http://cache.freescale.com/files/sensors/doc/app_note/AN1985.pdf .
I’m trying to sift through the passages near Fig. 3 to determine whether interdigitated (zigzag) pattern indeed could work as well as spiral pattern, for the printing of patterns on paper in Queen Mary. It makes a difference because then we could lay out the pattern as a border, whereas a spiral would have to be integrated differently into the page layout design. (I’m looking for a graphic designer to consult on the page layout.)
The spirals for inductive coils are tricky because you have to find a way for the center to cross the coils and head off somewhere else.
I am proud of my solution to this in the project with Jess Rowland where we replaced spirals with iterations of nearly closed C shapes. I don't know how
to make this design work at RF frequencies though. It might work but I am not equipped with the specialty tools...
PS. I notice that Table 2. Dielectric Materials with Different Thicknesses and Dielectric Constants
does not include paper among its materials tested. So there was room for a contribution to the state of the art in 1985 :)
Dielectric properties of paper have been heavily studied as it is popular dielectric material in transformers and capacitors:
http://news.3m.com/press-release/company/new-insulating-paper-3m-combines-dielectric-performance-and-durability.
Paper hasn't been used much in capacitive multitouch scenarios because of the horrible things skin-born materials do to regular organic paper.
The closest commercial devices to this sort of thing I can thing of are the polyamide smart cards used in the Montreal Metro (or SF Bart).
Topologies for conductors on paper: https://embodied.mpi-inf.mpg.de/files/2012/11/ACuttableMultiTouchSensor.pdf
(Note the capacitances in table 1)
https://www.kickstarter.com/projects/1597902824/agic-print-printing-circuit-boards-with-home-print
Adrian, thanks for is a remarkably spot-on reference :http://cache.freescale.com/files/sensors/doc/app_note/AN1985.pdf .
I’m trying to sift through the passages near Fig. 3 to determine whether interdigitated (zigzag) pattern indeed could work as well as spiral pattern, for the printing of patterns on paper in Queen Mary. It makes a difference because then we could lay out the pattern as a border, whereas a spiral would have to be integrated differently into the page layout design. (I’m looking for a graphic designer to consult on the page layout.)
The spirals for inductive coils are tricky because you have to find a way for the center to cross the coils and head off somewhere else.
I am proud of my solution to this in the project with Jess Rowland where we replaced spirals with iterations of nearly closed C shapes. I don't know how
to make this design work at RF frequencies though. It might work but I am not equipped with the specialty tools...
PS. I notice that Table 2. Dielectric Materials with Different Thicknesses and Dielectric Constants
does not include paper among its materials tested. So there was room for a contribution to the state of the art in 1985 :)
Dielectric properties of paper have been heavily studied as it is popular dielectric material in transformers and capacitors:
http://news.3m.com/press-release/company/new-insulating-paper-3m-combines-dielectric-performance-and-durability.
Paper hasn't been used much in capacitive multitouch scenarios because of the horrible things skin-born materials do to regular organic paper.
The closest commercial devices to this sort of thing I can thing of are the polyamide smart cards used in the Montreal Metro (or SF Bart).
Topologies for conductors on paper: https://embodied.mpi-inf.mpg.de/files/2012/11/ACuttableMultiTouchSensor.pdf
(Note the capacitances in table 1)
https://www.kickstarter.com/projects/1597902824/agic-print-printing-circuit-boards-with-home-print
Adrian, thanks for is a remarkably spot-on reference :http://cache.freescale.com/files/sensors/doc/app_note/AN1985.pdf .
I’m trying to sift through the passages near Fig. 3 to determine whether interdigitated (zigzag) pattern indeed could work as well as spiral pattern, for the printing of patterns on paper in Queen Mary. It makes a difference because then we could lay out the pattern as a border, whereas a spiral would have to be integrated differently into the page layout design. (I’m looking for a graphic designer to consult on the page layout.)
The spirals for inductive coils are tricky because you have to find a way for the center to cross the coils and head off somewhere else.
I am proud of my solution to this in the project with Jess Rowland where we replaced spirals with iterations of nearly closed C shapes. I don't know how
to make this design work at RF frequencies though. It might work but I am not equipped with the specialty tools...
PS. I notice that Table 2. Dielectric Materials with Different Thicknesses and Dielectric Constants
does not include paper among its materials tested. So there was room for a contribution to the state of the art in 1985 :)
Dielectric properties of paper have been heavily studied as it is popular dielectric material in transformers and capacitors:
http://news.3m.com/press-release/company/new-insulating-paper-3m-combines-dielectric-performance-and-durability.
Paper hasn't been used much in capacitive multitouch scenarios because of the horrible things skin-born materials do to regular organic paper.
The closest commercial devices to this sort of thing I can thing of are the polyamide smart cards used in the Montreal Metro (or SF Bart).
Topologies for conductors on paper: https://embodied.mpi-inf.mpg.de/files/2012/11/ACuttableMultiTouchSensor.pdf
(Note the capacitances in table 1)
https://www.kickstarter.com/projects/1597902824/agic-print-printing-circuit-boards-with-home-print
On Aug 3, 2014, at 6:31 AM, Adrian Freed <[email protected]> wrote:
If you can find someone to take this on at ASU, you might consider inviting Natalie and I there for a short residency to help kickstart their project.
Natalie has taught many paper electronics classes (she is doing one in SF next week). We also between us have many of the new materials
and unobtainium involved. You might want to invest in a printer for these inks:http://www.methode.com/sensors-and-switches/conductive-and-resistive-inks.html#.U926L1ZC7Vs
Methode has been doing this for 40 years.
This is the printer and materials kit link:
http://www.methode.com/news/Inkjet_development_kit.html#.U927llZC7Vs
These folk claim to be able to put it together in 3months:
https://www.kickstarter.com/projects/1597902824/agic-print-printing-circuit-boards-with-home-print
Their project was funded April 1st.
If you can find someone to take this on at ASU, you might consider inviting Natalie and I there for a short residency to help kickstart their project.
Natalie has taught many paper electronics classes (she is doing one in SF next week). We also between us have many of the new materials
and unobtainium involved. You might want to invest in a printer for these inks:http://www.methode.com/sensors-and-switches/conductive-and-resistive-inks.html#.U926L1ZC7Vs
Methode has been doing this for 40 years.
This is the printer and materials kit link:
http://www.methode.com/news/Inkjet_development_kit.html#.U927llZC7Vs
These folk claim to be able to put it together in 3months:
https://www.kickstarter.com/projects/1597902824/agic-print-printing-circuit-boards-with-home-print
Their project was funded April 1st.
On Aug 3, 2014, at 6:01 PM, Assegid Kidane <[email protected]> wrote:
I am waiting from the AGIC folks regarding the model of the printer in their system. The maximum paper size specification of the brother model that was discussed in various threads is A4 or US legal size. If the model in their package has the same specs we will be able to do our tests on standard office paper but we will not be able to run our 40cm paper through it. Perhaps we can make generalizing the process to many or all inkjet printers a new area of research. From the tests I have done so far, my recommendation is to utilize these circuit patterns/antennas with inductive or rfid sensing. With the teensy capacitive sensing, it is trivial to make a simple touch sensor. Making the system identify layers of paper is a whole different matter. The system produces larger data value changes for the slightest change of flatness of the first layer than for any creative pattern or size of conductor of subsequent layers. The interdigitation discussions referenced in earlier posts are mainly useful as multiplexers to increase the number of touch buttons from limited touch sensor i/o pins 'on a single panel'.
Gene Valentine is a local paper maker who has collaborated on the Paper Interiors project at AME before. We can try to get in touch with him if we need his assistance.
http://paperproject.org/exhibits/pidance/people2.html
I can think of Nicole Williams from our students to work with us, Todd, Loren, and David may have more recommendations.
Is it possible to have a Skype meeting to discuss what has been attempted to date?
I am waiting from the AGIC folks regarding the model of the printer in their system. The maximum paper size specification of the brother model that was discussed in various threads is A4 or US legal size. If the model in their package has the same specs we will be able to do our tests on standard office paper but we will not be able to run our 40cm paper through it. Perhaps we can make generalizing the process to many or all inkjet printers a new area of research. From the tests I have done so far, my recommendation is to utilize these circuit patterns/antennas with inductive or rfid sensing. With the teensy capacitive sensing, it is trivial to make a simple touch sensor. Making the system identify layers of paper is a whole different matter. The system produces larger data value changes for the slightest change of flatness of the first layer than for any creative pattern or size of conductor of subsequent layers. The interdigitation discussions referenced in earlier posts are mainly useful as multiplexers to increase the number of touch buttons from limited touch sensor i/o pins 'on a single panel'.
Gene Valentine is a local paper maker who has collaborated on the Paper Interiors project at AME before. We can try to get in touch with him if we need his assistance.
http://paperproject.org/exhibits/pidance/people2.html
I can think of Nicole Williams from our students to work with us, Todd, Loren, and David may have more recommendations.
Is it possible to have a Skype meeting to discuss what has been attempted to date?