Secret Tree Accepted at Maker Faire
I found out last week that the Secret Tree was accepted as part of the Maker Faire in San Matteo, CA. Unfortunately, the notice was a bit too short for us to be able to make the trip.
May 03, 2007
April 20, 2007
Gyroscopes
Images from the latest building session.
I made a solid wooden frame to hold one of the aluminum pulleys. There's a problem, though. The shaft exhibits a fair degree of wobble when the gyroscope is spun. During critique on Thursday, it was suggested that there should be a piece of metal in the hole so the bottom of the shaft will turn more smoothly. It would be even better to use bearings... which I've now tried.
I salvaged bearings from the read/write heads of two hard disk drives. Mounting the bearings was tricky, though, because they must be precisely aligned. This is even more difficult for me as my bearings aren't the same size. You can see this in my pictures of the PVC pipe gyroscope.
I think I would like to make a gyroscope frame out of metal pipe next.
April 10, 2007
[M/Bre]aking Things
My friend Mark P. Sullivan always said he wanted to make windchimes with all of the dead hard disk drives he had collected over the years. This came back to me as we struggled to find ways to make music with tops, so I started disassembling all of the broken drives I could find to listen to the sound of the platters
Case Mods
We modified our original protoype using one of the disk platters. Several small screws were placed within a cavity in the top beneath the platter in the hopes of making a sweet ringing sound. This was not successful. The centripetal / centrifugal (I always confuse them) force kept the screws jammed against the walls of the top as it spun so it didn't make any sound.
This is the best spinning top we have so far. Its proportions are comparable top those given in an article we found about machining tops from aluminum.
Whistling... Not Quite
I tried to drill holes in the platters, thinking it might be possible to get a whistling sound as the top spun. The only sound I produced was a pop as the platter shattered. It appears that the disk platters are not metals as I thought. They shatter like glass.
I constructed another test top out of a metal cone from a ceiling-mounted air vent we found on the junk shelf. I did my best to match the "ideal" top proportions.
This one doesn't spin very well -- and is quite dangerous when launched from the power drill.
April 09, 2007
Top-Related Links / Reference
Design
Top Design Principles
Machining Tops from Aluminum Stock
Beautifully Handcrafted Tops
Paper Clip Top
History
Where did the Spinning Top Come From
Every possible way to slice up the properties and names of tops....
Movies
The sounds Ian Russell gets out of his tops are quite diverse considering he is only using a ribbed wooden fruit bowl as a resonator.
Glossary
shaft - stem, peg
body
center of mass
axis
April 03, 2007
Update on Tops
This entry will catch up on some of our progress in creating a series of musical tops.
The week of our prototype presentation, we built a number of sample tops.
I also purchased two toy tops for a performance I gave in Designing for Constraints two weeks ago. One is a "BayBlade" and the other is a Duncan gyroscope.
I wanted to gain a better appreciation for how tops are constructed before we tried to make more of our own.
We discussed creating acoustic resonators for the tops to spin on and also tried to think of ways to make sounds with the tops. Qwanya (sp?) turned me onto the sound of tempered metals. She explained that her favorite sound in the Physical Computing Shop comes from the top right draw of the toolchest. The hole saws ping melodically whenever the drawer opens.
After presenting our prototypes in class, we received the following feedback:
- Become conversant in the vocabulary of tops
- Look at Taiwanese tops
- Consider the correlation between the tops and music. What is it?
- What about whistling tops?
April 02, 2007
Final Project Proposal - A Series of Tops
.what.
Greg Stringer and I will create a series of musical tops which act as an improvised toy orchestra. Each top in the series creates a distinct and pleasing musical sound. As multiple tops spin simultaneously, their musical sounds will combine into a larger homogeneous sound. The sound of several tops spinning together will be unique and fleeting; it will be difficult to spin the same tops in exactly the same order at identical velocities.
.why.
I'm interested in systems which enable musical improvisation among people who have the desire to create music but lack the technical competence on a musical instrument. The musical tops present a low barrier to music creation; they are found in many cultures and require little skill to operate.
Spinning tops transform from one shape into another. No matter the starting shape of a top, once it rotates it forms the shape of a circle. In recycling, a similar process occurs. The designed shape of an object, after its operating lifecycle is complete, is transformed back into raw material and then back into a new designed object. The rotation of our tops will refer to this process.
.how.
The tops will be constructed from salvaged parts to highlight the theme of reuse and the cycle of products from raw material to designed object and back to raw material.
Several types of tops will be created to provide desired musical properties: percussive and melodic sounds.
March 31, 2007
Improvised Musical Instrument Links
March 28, 2007
Final Project : Concept Development
The Final project for Living Art will adhere to the following process:
Concept Development
Prototype
Build
Refine
Present
Earlier this week, Ji-Sun Lee and Youjeong Paik approached me about collaborating on the final project. I was still on the fence about whether to try combining my Audio Art final with this final.
Ji-Sun, Youjeong, and I brainstormed plant-like ideas yesterday. Today, So-Young joined us for a bit. We played around with a number of ideas.
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At the end of our session today, we ended up gazing at the stars.
What: Make a Wish
"Make a Wish" is an immersive environment that offers the participant an opportunity to gaze into the night sky and make a wish on a falling star.
Why
- Ji-Sun and Youjeong visited an exhibition recently of an artist who uses mirrors to create infinite interior spaces. We want to explore this idea further using realism rather than surrealism.
- This project shares some common themes with our Secret Tree project: the need to express certain interior realities privately and private public spaces.
How
- Fiber optic strands will be used to simulate stars in the night sky
- Stars to be dimmed using AD5206 digital potentiometers
- Immersive environment sound using stereo speakers
Challenges
- Shooting star effect
Secret Tree on TechTrek.tv
Special thanks to Caleb Clark, Anh Nyugen, and Rucyl Mills for their awesome work in filming the Secret Tree.
March 24th, 2007. New York City.
Episode 4: 4 minutes
Wherein we take at Michael, Aichen and Sun's Physical Computing project "Secret Tree.
- Secret Tree: http://itp.nyu.edu/~jsl398/tree/Â
They have more episodes at http://techtrek.tv
March 03, 2007
Secret Tree Schematic
Last night, in preparation for building a perf board, I drew a first draft of the schematic for the Secret Tree.
There are several things to do yet to properly document the project's electronics:
- Add the clock crystal and other required components for the ATMEGA-8
- Draw a system block diagram
- Draw the finite state machines (although this may be overly complicated
Anyone have suggestions on how to simplify this schematic?
March 02, 2007
More Trouble
This afternoon I attempted to connect the Secret Tree circuit board to the LEDs on the tree. Since my test program (adapted from an Arduino tutorial) appeared to be working well I was ready. The first six LED clusters I connected to the terminal blocks worked fine, but the seventh and eighth clusters didn't operate properly. I tried resetting the Arduino board as well as the MAX patch, but things wouldn't work consistently. I even saw that a single LED connected to the seventh output didn't light up consistently. Once I disconnected all of the clusters and returned to single LEDs, the system seemed to function properly. Maybe the LED clusters are drawing too much current and are causing the digital potentiometers to behave erratically.
Back at home, I found a small breadboard wiring problem: I didn't have a proper connection to ground for the pins 15, 18, 19, and 22 on the second AD5206. Even so, the LEDs connected to the potentiometer outputs related to those pins still lit up. My correction only served to properly extinguish the LEDs when I set the potentiometers on that side of the chip to the maximum 10K resistance.
The light blue wire connected to ground above the AD5206 is the recent addition.
So far, I have tried the following in order to get the software/hardware system working:
- Corresponded with Scott Fitzgerald regarding the MAX patch. He removed the multiple "metro" objects from it and recommended running the system at 9600 baud so as not to overwhelm the PC's serial buffer.
- Spoke with Leif Krinkle about the MAX patch. He questioned my use of the SimpleMessageSystem for MAX and thought I would be better served by a basic home-brew protocol. I started rewriting the Arduino code and the MAX patch to use a simple protocol based on sending Arduino six bytes of information from MAX using the "pack" object". I originally asked him how to debug the MAX patch since Arduino and MAX were communicating over the Arduino's only serial port. It turns out that there is a software serial library that could be used to do this type of debugging.
- Discovered in the course of rewriting the serial protocol that the switch needs debouncing. This is the source of the strange values I saw in MAX/MSP with my new serial code.
Tomorrow I will try using a power supply with more amperage to see if that improves things. Any other suggestions?
February 28, 2007
Chip Select on AD5206
Ai-Chen and I did a bit of rewiring on the Secret Tree circuit board. One of the problems we had last week was that all of the ground wires for the LEDs on the trees were connected to two PCB terminals. I didn't purchase enough terminal at RadioShack so that every pair could have a ground of its own. This not only made things messy, but it also made the connections suspect.
The other major discovery I made which explained much of the circuit's random (unintended) behavior was that the two AD5206 chips interfered with one another. I plugged a single LED into each of the twelve outputs (across the two chips) and found that a simple test program didn't operate properly when both chips were running. As soon as I disconnected the three data lines (CLK, SDI, and CS) from the second chip, the first chip would work properly. I wondered if there might be some sort of "floating" condition when the two chips were used together. Since CLK and SDI were shared, I hypothesized that CS was likely the culprate. To test this, I added 10K pull-down resistors on the chip selects of both chips. It worked! The test program dimmed the lights in the proper sequence rather than skipping around randomly on the third and fourth outputs.
February 26, 2007
Secret Tree Pictures
We presented the Secret Tree in class on Thursday. Although the MAX patch didn't work, the piece was well-received. We are in the process of finishing the piece for our midterm presentation.
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February 18, 2007
Secret Tree Progress
Work continues on the Secret Tree project. Today we finished cutting out the branches, building a support framework, and unfolded it for the first time. It was almost magical.
February 11, 2007
Make A Random: Secret Tree
I'm working with Ji-Sun Lee and Ai-Chen Lin on a "secret tree" for Living Art. Our assignment is to "Make a Random."
You can approach the tree and tell it a secret; in fact, it may be that the tree needs to be told secrets in order to stay alive.
Ji-Sun has already constructed a prototype tree.
Ai-Chen and I have been working on MAX/MSP and Arduino code prototypes to record the secrets and transform them into lights on the tree.
February 07, 2007
A Simple Set of Rules v0.1
This is a low-tech piece which considers the differences between humans and computers.
Consider for a moment that all computers know how to do at a fundamental level is deal with bits of information: ones and zeroes strung together in finite lists.
Consider for a moment that any "creativity" a computer possesses has been given it by a human programmer.
Let's further constrain our thinking to the process of drawing. Computers "draw" using pixels, or discrete bits of information. We create using continuous lines. We put pen or pencil to paper and the inspiration flows out of our minds and onto the page. Even constrained, we have infinitely more imagination than a computer.
Let's confine ourselves to rectangles and a simple set of rules
Equipment
- Felt-tipped pen
- 8.5" x 11" sheet of paper
- Please read all rules before beginning
- Use the provided felt-tipped pen to draw a rectangle on the paper
- If the paper is blank, you may draw a rectangle of any size anywhere you wish on one side of the paper
- If the paper is not blank, please follow the following guidelines
- Your rectangle must be drawn on the same side of the paper as existing rectangles
- Your rectangle must be drawn outside of any existing rectangle
- Your rectangle must not intersect any existing rectangle
- After you have drawn a rectangle, ask someone else to draw the next rectangle
- The drawing is finished when it is no longer possible to satisfy the above conditions
January 30, 2007
Magic Flute
I've built a "Magic Flute" for my Living Art Finite State Machine project.
The Magic Flute is a simple wind-style MIDI controller interface which can play all of the notes in a C-major scale. I'm a keyboard player by training, but I've always wanted to try playing a wind instrument -- particularly the clarinet.
The major purpose of this assignment, however, was to create a Finite State Machine:
As we discussed in class, the Finite State Machine is characterized by inputs, outputs, and a memory of previous states. In the case of the Magic Flute controller, the inputs are the keys. The outputs are a slight clicking sound as the keys contact the body of the instrument, but more importantly the MIDI messages the controller sends. The memory is in the code that runs on the ATMEGA chip on the Arduino board. The code remembers which buttons were pressed and sends MIDI messages according to the Finite State Machine.
You may notice that there is no mention of wind pressure in the Finite State Machine. I spent the better part of last weekend trying to get a sound level circuit to work. The circuit I used worked fine for amplifying audio, but was very unreliable when I tried to use Arduino to measure the amplitude of sound coming into it.
I came up with some other possibilities for measuring the wind speed inside the controller:
- Using a tiny encoder wheel with a opto interrupter to measure the speed
- Looking for a vibration sensor that outputs a good signal
- Hot-wire anemometer
There are some other extensions I would like to make to the controller's firmware if I have time to build it again:
- A button-triggered mini sequencer function so I can record and playback a short motif. This could be really cool for live performance. I could sample a short loop as accompaniment and then play a live melody on top of it. - A transposition function so I can play notes outside of the C-major scale
- Key combinations to allow me to play semitones which are fundamental to playing other scales
- A volume knob
