Tuesday, April 22, 2014

Cheap materials and small surprises

One of the most rewarding and yet frustrating things about these projects is that you sometimes need to commit yourself to an idea before you fully understand all of your options.

For instance, my array of infrared LEDs and receivers (pictured below in all of its hot-glue-and-gaffer-tape glory), though effective, does not implement any of the various light tuning/focusing techniques I've discovered in only the last few days, far too late to incorporate into my design.

On the other hand, despite hours of research into rear projection materials and advice from fellow artists/technicians, the $3 white vinyl shower curtain that I'm using on the back of the glass panel as a projection surface works like gangbusters.

Also, despite my disappointment with the amount of tape, glue, and foam core that went into this design, the fact that the glass "wall" looks somewhat presentable (aside from the wood blocks clamped to the bottom, which will be painted) is a testament to the fact that sometimes it's only the surface (the illusion) that matters. If you can convince the viewer that you've made something seamless and solid, then it doesn't necessarily matter how much of a mess you're hiding behind that foam core!

Lastly, my plan for the projected visual material is to use macro-ish and/or textural photos from the space in which the walls are being installed (DL1). Here are a few of my favorites so far (I'm hoping to go even more abstract for the final versions):

Friday, April 4, 2014


Umm... Woah:


I guess putting micro controllers and sensors in balloons isn't so crazy after all.

Thursday, April 3, 2014

panGenerator - constellaction

This is the installation work I cited in my presentation today. In general, the group has a set of very interesting interactive installation other than this one. You can check out their website (pangenerator.com)


Wednesday, April 2, 2014

Lights on the walls

Just wanted to share some of my discoveries/research from the last couple of days.

First of all, the good news: I got some super cheap glass panels from the ReUse center. $5 each.
I went with 2 different kinds to see which I liked better. I'm not totally sure yet whether I like the idea of having 3 different walls or 3 identical walls. Hopefully if I chose the latter, they'll have enough of the same glass to chose from. There were definitely more of the smaller version sitting in the warehouse.

Also, research on AV forums has lead me to discover that cheap shower curtains actually make pretty decent rear projection surfaces. Not as good as the real thing, but for $3-6 a pop, I'll take it.

Now, the actual sensing is getting kind of hairy. Despite my delusional wishing, a standard infrared proximity sensor has an extremely narrow range (about an inch wide). I kind of expected that, but figured I should test it anyway. While the prospect of lining the side and top of the glass with dozens of these sensors is interesting, it's also too damn rich for my blood at $15 a pop.

So, my options as of now are the following:

Option #1: IR Receiver with an array of infrared LEDs

This option seems the most promising as these sensors have a wide viewing angle and are tuned to look for modulated IR light @ 38khz. It takes the job of detection off of the computer and only sends digital on/off. Plus, this is a cheap option! A pack of 25 infrared LEDs was $8, and each of these sensors is $2. I'm hoping I can get away with using, at most, 3 sensors per wall, pointing down.  Also, skin and hair easily reflect IR light, which I confirmed by pointing a remote control away from a DVD player and getting the signal back to the sensor by putting my hand and head in the light's path. The main challenge here will be modulating the LED pulses from an Arduino and getting enough current to them. There's also the issue of making sure that nothing else in the path of the light (i.e. on the floor) will reflect light back to the receiver. Glass is apparently very good at absorbing infrared (see Mythbusters).

Option #2: Infrared emitter/detector pair

I suspect that this is nothing more than the LED and receiver components from within a proximity sensor without the other circuitry. My concern is that this will not have the range or angle of view that I need, and I was not able to find this info online, but they were cheap so I ordered a pair to try it out. The benefit here is again doing all the detection on the Arduino with the added bonus of not needing to worry about modulating the LED.

Option #3: PS3eye

Back to camera detection. This is my least favorite option (most expensive, most difficult to setup in software, takes CPU resources, puts me back in Jitter land, might not be able to get 3 of these cameras working on a mac, etc). But, if I get it working, it's also the most robust. I could try to do things with location if I want. There's a lot of info out there about how to remove the IR filter from this camera, it's only $10 used at Gamestop (though I'll need 3 if this works), and I was happy to discover that the magnetic film from within a floppy disc (of which I was able to locate 2 in Groundworks) acts as a pretty good visible light filter.

Should have more to share before next Tuesday.

Also, on a side note, Chris Sies (the graduate percussionist) had a recital last weekend, and his parents were in town. Turns out his dad used to own a metal shop, and he was super intrigued by the Metal Mirror. He seriously sat and played with it for at least half an hour. It was great.

Monday, March 31, 2014

OpenCV in Processing

I'm still looking into the best option for blob detection for my project.
Came across this and couldn't help but laugh- the music really helps to sell the good vibes:

Friday, March 28, 2014

An article on audience participation in interactive installations

One more paper worth checking

Winkler, Todd. "Audience participation and response in movement-sensing installations." Proc. of the International Computer Music Conference (December 2000). 2000.


Wednesday, March 19, 2014

Conductive Yarn = Non-Consistent Sensing Mechanisms!

There is no disclaimer for this online so I would like to put this piece of information first (in case anyone is googling this like I was):


It doesn't necessarily claim otherwise anywhere, but it seems like it's important to address explicitly. Generally, if using conductive or resistive yarn, you are going to have to calibrate the sensing mechanisms for each yarn sensor you make unless you make it with a certain kind of scientific precision that most home-based DIY-ers can't count on. There are many really excellent resources for building sensors at the How To Get What You Want database.  I tried to make this conductive pom-pom, which is indeed a variable resistor but not a very reliable one. Threads kept coming out and the range would keep on changing. I ended up changing my project to rely on a force sensitive resistor (FSR) instead.

Here's a video of how the pom pom was supposed to work:

this blog post is meant to be utilized as a road sign at the fork between making yarn sensors or not.
It can be tricky


Tuesday, March 18, 2014

Moments of Warmth.

A simple interactivity @ a but stop can be heartwarming. Maybe we should create another version of this so that we can turn non-huggers into huggers.

Nedko Solakov

Half of this video is in German, but it's one of the better examples I've seen of Nedko Solakov's use of the features in a space to tell little stories and create little characters.

Thursday, March 13, 2014

coded sensation


tape head on figners, a cloth made of tape reel, and a musician who rubs his body.


Wednesday, March 12, 2014

Surround Sound Umbrella

Since we're moving on to the topic of installations, I thought I would share this interesting article posted on Create Digital Music a few days ago:

A Surround Sound System You Can Carry Like an Umbrella, ‘Anywhere’

::vtol:: "anywhere" from ::vtol:: on Vimeo.

Would have been interesting to see them include an interactive element (perhaps simply using spatial movement as input), but pretty cool tech.

Monday, February 24, 2014

Squeezing things

I made a resistive yarn ball that gives more resistance when you squeeze it from the "How to Get What You Want" guide (sounds suspiciously like a self-help book) found at kobakant.at. It is a very approachable guide on how to make variable resistors and switches with textiles. Tomorrow I'm going to attempt to wrap another conductive ball with an accelerometer inside as control for an experimental instrument I am attempting to make musical, the interface being based around squeezing and turning this conductive ball.

 In addition, I finally looked into the outcomes of the Guthman competition and there is a video of a very similar interface for an instrument called "


(homage to the Sonic Banana?)
of which some entertaining video documentation can be found here

I once found this postcard from Poland with a really strange looking hotdog on it

More on this later,

Sunday, February 23, 2014

Better contact mics

As you may already know, my metal plate project will be utilizing a couple of contact mics for amplification and controlled feedback.
One of the downsides to the cheap piezo transducers is that, for electrical and mechanical reasons that I don't totally understand, a DIY contact mic without a preamp has a resonant peak in the response and can't reproduce low end well.
To that end, I am going into the workbench this afternoon to make a couple of preamps using this design:

Wednesday, February 19, 2014

Guitar Wing

Even though we're intentionally avoiding augmented instruments with our first project, I wanted to share these videos I found of the Guitar Wing since augmented electric guitar and the use of electric guitar in new music is something that interests me a great deal.

That being said, the results in these videos are pretty cheesy, and I would say that they don't so much extend the abilities of the guitar as they simply put buttons and sliders in easy ergonomic reach for the guitarist.

Still, I think it's a step in the right direction, or at least a good sideways step.

I expect people that use the Guitar Wing will end up playing finger style (forgo a pick) a lot more than they used to.

The Robocaster was actually an early prototype made (I think) by Moldover that inspired the Guitar Wing:

This is Moldover using the finished production model- the most important point to note is that it can be added to an existing guitar without modification:

Monday, February 17, 2014

Digital Panel Joinery

For those laser cutting cases and boxes, check out this post on digital panel joinery. Lots of design ideas. http://makezine.com/2012/04/13/cnc-panel-joinery-notebook/

Sunday, February 16, 2014

Just came across this, dont know how many have seen it. Think it might be of interest to some... [=

Future Self by rAndom International

Sunday, February 9, 2014

Guthman Musical Instrument Competition

Every year, Georgia Tech. School of Music holds a competition on new musical instrument. Here's the list of semifanlists this year.

Hope we can see some projects from this class next year.

See hear for more details : http://guthman.gatech.edu/2014-semi-finalists

Daniel Novy
Chester Udell
nu desine
Yuto Hasebe
Teenage Engineering
Tolgahan Cogulu
Francesca Fini
Stegano Fasciani
Berendan McCloskey
Margariet van Eekelen
Edward Ptokar
John Driscoll
Uday Shankar
Amit Shoham
Yoshihito Nakanishi
Ian Hattwick
Mailis Rodriques
Michael Shonle
Feng Gao

Tuesday, February 4, 2014

1DOF Haptic Devices

Those interested in haptics may want to check out http://eduhaptics.org/, which has a section devoted to 1 degree-of-freedom "Haptic Paddles:" http://eduhaptics.org/index.php/HapticDevices/HapticPaddles.

Furthermore, check out the "Hapkit:" http://hapkit.stanford.edu/.


Came across this while researching "amplified ceramic".

Not necessarily 100% relevant, but I thought it was lovely and worth sharing!
I guess technically it could be interactive if the spectators were willing to get wet.

Thursday, January 30, 2014

Squeezable - Gil Weinberg

This post is something that I thought it is relevant to Isaac's idea, although I am not sure if you already present this work for your reference because I came late. So bear with me if you've already seen this.


If you read the paper, there is distributed nature that each ball has a different function in a sound generation sequence. You can find the paper at http://www.mitpressjournals.org/doi/abs/10.1162/014892601750302570?journalCode=comj

Unfortunately, I couldn't find a video.

(Oral) Cavity / Audio Feedback

I am still sicking with this oral cavity idea, unfortunately, although I think it's going to be amazing if everything works as imagine.

The main idea is not to reproduce a talkbox (human voiced musical instrument) but to use oral cavity (or any cavity in general) to close an acoustic feedback loop in the middle.

The closest musical example I could think of is, of course, Sitting in the room by Alvin Lucier.

There are two differences in this project from Lucier's piece. First, here the cavity I choose (it may or may not be oral cavity) takes the role of the room, which I can dynamically change because of the small scale of the cavity I chose (or the variety of the cavity). Second, instead of keep recording the playback of the recording iteratively, I create a direct feedback by putting the cavity between a mic and a speaker.

Even though I can generate sound without any sound synthesis algorithm just by connecting speaker directly to microphone just by closing the feedback loop with the cavity, there will be sound processing in the middle so that I have more control on sound with a set of sensors.

The other piece similar to this idea is Pendulum Music by Steve Reich given I utilize audio feedback. I will skip the video because it's already there.

It's always nice to look at some example from human vocoder/sonovox/talk box (although that's not the idea ) because the apparatus that I will create may look very similar to talk box,

The main difference is that speaker (hose in the case of talkbox) will play a processed sound of mic input. It will sound nothing like a synthesized voice even if it is processed via oral cavity. The only advantage of oral cavity in this scenario is that I can control the shape of the cavity.

Wednesday, January 29, 2014

Mini-Seesaws and Haptics

I have been branching off from the idea of a seesaw, or small balance that the user would use to create musical sounds based on it's position. Here are some of the possibilities I have been exploring - all of which could be pursued in further depth.

 Ideally, there would be a number of these small seesaw controllers that a user could use for a polyphonic performance of sorts. Each seesaw could involve a slider to add another degree of freedom, or a mass that might shift loosely. Another option is to design the instrument to be played by two people - taking on a collaborative, or adversarial nature.

While looking for related work I stumbled across this video, which is not a music controller, but is an elegant example of robotics. It gave me the idea to potentially incorporate a rolling ball that the user positions by moving the balance.

No matter what form the seesaw aspect takes, I hope to incorporate some form of haptics into its design. "Haptic" comes from the word touch, and in the context of interactive systems,  haptics is any force, vibration or motions applied to the user. The method I plan on pursuing has been used in other haptic musical controllers, such as The Plank, which uses dynamic force feedback to create a tactile topography. In other words, as one moves the device, it simulates the feeling of plucking strings or pushing over bumpy surface. This effect is created by selectively applying force against, and along with the motion of the user. For example, if there is a sudden discontinuity in the applied force, jumping from a positive extreme to a negative extreme, the simulated action will present itself as a pluck (see The Plank for more information). Some other notable examples of haptic controllers include the Phantom and the Novint Falcon.

Incorporating haptics into my seesaw controller would hopefully allow the user to develop a more intimate relationship with the feeling of the system, fostering a sense of control while building a difficulty curve into the learning on the instrument. It would be interesting to see how incorporating force-feedback into a seesaw motion might provide a musical interaction.

Metal Vibrations

The project that I'm pursuing is centered around a performable metal plate driven by a surface-mount transducer.

The most common example of such a system is a "plate reverb", a method for reverb very popular on recordings from the 1960's and 1970's.

Here is a great video discussing and demonstrating a typical plate reverb and how it sounds:

So, the basic components include a large, thin steel sheet, a driver, and a pickup.

Some of the research that I've done so far indicates that the size and stiffness of the plate is incredibly important. The typical goal with reverb is to have a large number of lush resonances so that no specific frequencies are obviously dominating the others.

My goal is kind of the opposite: I want a handful of very strong resonances that ring clearly. Probably more like what you'd get from a cymbal. Although cymbals are very noisy when hit, you'll still get a handful of very strong frequencies that pop out when you bow a cymbal. You can kind of hear that effect in this video:

Earlier this week, I played around with some steel plates around 3' X 2' and 1/8" thick (considerably thicker than the 1/64" typically used for plater reverbs) and was getting very gong-like sounds, even when bowed:

Fun fact: the sickly looking character in that video is Silas B from Madison who I ran into a few times when I lived there. It just happened to be the first video result that came up when I searched for "bowed gong". He had a lung transplant just before I moved, so I suspect that he is doing much better these days. http://silasritchie.bandcamp.com

Anyway, I'm excited about bowed-gong-like sounds.

Bought a couple of these last week, so audio testing will begin soon.

Tuesday, January 21, 2014

Swinging Objects / Pendulum

I notice some of you have ideas that can be somewhat turned into pendulums (or swinging/flying objects.)

These are some of the videos I found when I did game 3(swinging rocks!) last year.

Pendulum Music - Steve Reich.

Gordon Monahan - Speaker Swinging

Pocket Gamelan -  Greg Schiemer

mPoi : Musical Poi - Sangbong Nam (there's a paper about this in NIME 2013)

This video is NOT a music piece but you MUST look.

I think pendulum has a limited control for musical expression ( due to the repetitive nature? ) but maybe it is an ideal apparatus to have phasing in music.


Tuesday, January 14, 2014


Well, I don't think this is a typical example of NIME but today's class reminded me of this video and made me want to revisit especially when we talked about intentionality/purpose ( or tennis sonification vs tennis piece @ Belfast)

I think this makes an interesting case regarding design dimensions of performance system that are covered today.

  • I personally think that there's definite intention of "musical expression."  (as opposed to plain juggling balls, or sonifying tennis). 
  • Look how far he can push further with this simple interface. I think there is more room for virtuosity than you thought. 
  • "The physical model" of the interface extremely constrains "temporal dynamics" of sound it can make (well there are a set of rhythmic patterns he can play but nothing much more than that), which naturally makes the system very limited in style/diversity/wall (even though it has a high ceiling.) 

"33" Breath Controller

I'm still a little unclear as to what exactly is going on with this breath controller...
Unfortunately, it's not a breath-controlled "Ebow" effect as I was hoping.
Rather, it's a MIDI controller that combines breath control with essentially a joystick (X-Y control).
Johan Haake, the brother of Meshuggah's drummer, originally built these back in 2002 or so. Frederik Thordendahl, one of the guitar player's in Meshuggah, was using a Yamaha breath controller but wanted something more performable, and Johan asked if he could give it a try.
There's a lot of great info, including development history and schematics, at Johan's site: http://www8.tfe.umu.se/personliga/jh/index.html.

Here is a pretty good demonstration video (not by Frederik Thordendahl):

Here is an example of it being used in a Meshuggah song for a guitar solo (starts around 2:40):

Friday, January 10, 2014

Intel Galileo

Exciting news!

Thanks to a donation from Intel, we're about to be recipients of 5 brand new Intel Galileo boards. Galileo is a collaboration between Intel and Arduino to create a next-gen Arduino-compatible development board with more powerful Intel processors. Lots of exciting features: a 400MHz 32-bit processor, Ethernet, PCI express, MicroSD connector... This is a maiden voyage of sorts--the technology is very new, but we have the opportunity to be part of it. Here is some preliminary documentation from Intel and from Arduino.

Tuesday, January 7, 2014


This is the class blog for PAT 452/552 –– Interactive Media Design II — in the Department of Performing Arts Technology at the University of Michigan. This is where we're going to post sketches, photos, videos, inspirations, ideas, and miscellany as we develop interactive performance systems and art installations.