Most projects have one or two significant aspects in which custom work or clever execution is showcased, but this Music Box Hole Punching Machine by [Josh Sheldon] and his roommate [Matt] is a delight on many levels. Not only was custom hardware made to automate punching holes in long spools of paper for feeding through a music box, but a software front end to process MIDI files means that in a way, this project is really a MIDI-to-hand-cranked-music-box converter. What a time to be alive.
The hole punch is an entirely custom-made assembly, and as [Josh] observes, making a reliable hole punch turns out to be extremely challenging. Plenty of trial and error was involved, and the project’s documentation as well as an overview video go into plenty of detail. Don’t miss the music box version of “Still Alive”, either. Both are embedded below.
[Sam Kent] and friends built a sound-reactive LED display as part of the Leeds (UK) Digital Festival and exhibited it at Hyde Park Book Club. The installation consists of a grid of 25 tubes, each one made out of four recycled 2-liter bottles equipped with a string of a dozen WS2812B LEDs controlled by a central Arduino.
Connected to the Arduino via USB, a computer running a Processing application analyzes the audio input and tells the Arduino which LEDs to light and when. The red tube in the center responds to bass, the ring of yellow LEDs mids, and the outer ring glows blue in response to high frequencies.
It’s amazing how just a simple 2-liter makes a rather effective light pipe to amplify the effect of each burst of color. We think this installation would be a great addition to the magnificent LED dance floor we recently looked at from our friends up in Toronto. If you seek an LED art piece that’s a lot easier to move around, what you’re after is a rave shopping cart.
[carykh] took a dive into neural networks, training a computer to replicate Baroque music. The results are as interesting as the process he used. Instead of feeding Shakespeare (for example) to a neural network and marveling at how Shakespeare-y the text output looks, the process converts Bach’s music into a text format and feeds that to the neural network. There is one character for each key on the piano, making for an 88 character alphabet used during the training. The neural net then runs wild and the results are turned back to audio to see (or hear as it were) how much the output sounds like Bach.
The video embedded below starts with a bit of a skit but hang in there because once you hit the 90 second mark things get interesting. Those lacking patience can just skip to the demo; hear original Bach followed by early results (4:14) and compare to the results of a full day of training (11:36) on Bach with some Mozart mixed in for variety. For a system completely ignorant of any bigger-picture concepts such as melody, the results are not only recognizable as music but can even be pleasant to listen to.
What’s better than 1 string of LED lights? 96. That’s how many. Each string of the 96 has 60 ws2812b LEDs, for a total of 5760 individually addressable RGB LEDs. That’s not the cool part of [jaymeekae]’s Space Tunnel installation, the cool part is that they’re interactive.
Starting out with some PVC piping, dark cloth was used as a backdrop and the LED strips were attached to it. Several power supplies are used to supply the voltage necessary and each strip controlled by FadeCandy chips which connect to, in this case, a Windows PC via USB. Initially, computer power supplies were used, but they couldn’t supply the current necessary. [jaymeekae] used them for the first installation, but switched to better power supplies for further installations.
Once the lights were up and powered, [jaymeekae] started work on the interface to control them. Starting with a used bureau, [jaymeekae] cut out a section for the touchscreen, and installed the controlling computer in the bottom half. Processing is used to interface with the FadeCandy controllers and HTML is used for a user interface. Each mode runs a different Processing program for different effects, including audio visualization, a space tunnel mode (hence the name) and a cool drawing app where the user draws on the touchscreen and sees the results in the lights overhead.
Over several iterations, the Space Tunnel has evolved, with better power supplies and a better interface. It’s a great art installation and [jaymeekae] takes it to festivals, including one in Spain and one in the UK. There are some other LED string projects at Hack-a-Day, including this one with ping-pong balls, and this one that involves drinking a lot of beer first.
Many of us have held a circuit board up to a strong light to get a sense for how many layers of circuitry it might contain. [alongruss] did this as well, but, unlike us, he saw art.
We’ve covered some art PCBs before. These, for the most part, were about embellishing the traces in some way. They also resulted in working circuits. [alongruss]’s work focuses more on the way light passes through the FR4: the way the silkscreen adds an interesting dimension to the painting, and how the tin coating reflects light.
To prove out and play with his algorithm he started with GIMP. He ran the Mona Lisa through a set of filters until he had layers of black and white images that could be applied to the layers of the circuit board. He ordered a set of boards from Seeed Studio and waited.
They came back a success! So he codified his method into Processing code. If you want to play with it, take a look at his GitHub.
[Mr_GreenCoat] is studying engineering. His thermodynamics teacher agreed with the stance that engineering is best learned through experimentation, and tasked [Mr_GreenCoat]’s group with the construction of a vacuum chamber to prove that the boiling point of a liquid goes down with the pressure it is exposed to.
His group used black PVC pipe to construct their chamber. They used an air compressor to generate the vacuum. The lid is a sheet of lexan with a silicone disk. We’ve covered these sorts of designs before. Since a vacuum chamber is at max going to suffer 14.9 ish psi distributed load on the outside there’s no real worry of their design going too horribly wrong.
The interesting part of the build is the hardware and software built to boil the water and log the temperatures and pressures. Science isn’t done until something is written down after all. They have a power resistor and a temperature probe inside of the chamber. The temperature over time is logged using an Arduino and a bit of processing code.
In the end their experiment matched what they had been learning in class. The current laws of thermodynamics are still in effect — all is right in the universe — and these poor students can probably save some money and get along with an old edition of the textbook. Video after the break.
You know Processing? It is the programming language and IDE aimed at the electronic arts, new media art, and visual design communities. [Gottfried Haider] recently got Processing working on the Raspberry Pi and included a hardware input/output library to manipulate the Pi’s I/O pins.
If you want to experiment with Processing, you can download it right on your Pi with the following command:
curl https://processing.org/download/install-arm.sh | sudo sh