Located in Kitchener, Ontario, Kwartzlab is a 3000 square foot hackerspace. In 2009, the group was founded and set up their space in a former box factory. We dropped by the space on one of their Tuesday Open Nights to take a tour. Join us after the break for a quick walk through of Kwartzlab.
This unique electronic instrument combines a chopped up guitar and a hacked apart glockenspiel with an Arduino. [Aaron]’s Glockentar consists of guitar hardware and glockenspiel keys mounted to a wood body. Solenoids placed above the keys actuate metal rods to play a note.
Under the hood, an Arduino connects the pieces. The conductive pick closes a circuit, which is a digital input into the Arduino. This actuates the corresponding solenoid to play the glockenspiel key, and sends a character to a computer over serial.
On the computer, an openFrameworks based program creates lighting that is projected onto each string. MadMapper is used for projection mapping, which maps the openFrameworks output to each string. Video is passed between applications using the Syphon framework.
[Aaron] has provided a write up that goes into details, including the Arduino and openFrameworks source for the project. There’s also a video overview and demo of the Glockentar after the break.
Continue reading “Glockentar: A Guitar + Glockenspiel Mashup”
[Ben Krasnow] built his own version of the TSA’s body scanner. The device works by firing a beam of x-rays at at target. Some of the beam will go through the target, some will be absorbed by the target, and some will reflect back. These reflected x-rays are called ‘backscatter‘, and they are captured to create an image.
In [Ben]’s setup a rotating disk focuses x-rays into beams that travel in arcs across the X-axis. The disk is moved along the Y-axis to fill in the scan. On the disk assembly, there is a potentometer to measure the y-axis position of the beam, and an optical sensor to trigger an oscilloscope, aligning the left and right sides of the image. Using these two sensors, the scope can reconstruct an X-Y plot of the scan.
To detect the x-rays, a phosphorous screen turns the backscattered x-rays into visible light, and a photo-multiplier amplifies the light source. A simple amplifier circuit connects the photo-multiplier to a scope, controlling the brightness at each point.
The result is very similar to the TSA version, and [Ben] managed to learn a lot about the system from a patent. This isn’t the first body scanner we’ve seen though: [Jeri Ellsworth] built a microwave version a couple years ago.
The impressive build does a great job of teaching the fundamentals of backscatter imaging. [Ben] will be talking about the project at EHSM, which you should check out if you’re in Berlin from December 28th to the 30th. After the break, watch [Ben]’s machine scan a turkey in a Christmas sweater.
The folks over at the Raspberry Pi Foundation often gets asked “does it run Minecraft?” Mojang, the team behind the block building game, has announced that they will be releasing Minecraft: Pi Edition. This port will be based off the Pocket Edition of the game, but with a revised set of features.
So what does this have to do with hacking? Mojang has announced that the Pi Edition will have “support for multiple programming languages.” There aren’t too many details about what this support will entail, but it looks to be aimed at teaching programming by using the world of Minecraft.
Hopefully, it will be possible to interface with the RPi’s expansion header to allow external devices to get data and create objects in the Minecraft world. There’s a lot of potential for hacking and learning programming skills.
The best part? It will be a completely free download. We’re looking forward to the launch.
[Steve] created an AVR programmer using an old USB keyboard. We feature a bunch of AVR programmers, but this one is made from parts that many people will have lying around. There are two components: the controller PCB from a USB keyboard, and an optocoupler for emulating key presses.
In order to send data to the AVR, [Steve] used the LED outputs on the keyboard. These LEDs can easily be toggled according to the HID device specification. They provide a 5 volt output with current limiting resistors, which means they can be connected directly to the target AVR.
Reading data is a bit more complex. The optocoupler tricks the keyboard into believing that a single key has been pressed, firing off a data transfer. The MISO pin on the AVR is connected to the row and column of the shift key, which is read by the driver.
On the software side [Steve] created an avrdude interface driver. This allows the programmer to be used with avrdude, just like any other programmer. [Steve] does point out that it isn’t the fastest programmer since the keyboard tries to debounce the MISO input, greatly limiting the speed. However, since it’s made from stuff you might have in your junk bin, it’s a neat hack.
We’ve seen a few 1-D pong games recently, and they’ve all be controlled using microcontrollers. Inspired by some of these hacks, [mischka] built the monoPong using a handful of logic chips.
The monoPong has four major components. A 555 timer in astable mode provides a clock source which is fed into a 4510 decade counter, which connects to a 4028 BCD to decimal decoder to drive the LEDs. Finally, a 4011 NAND gate IC is used to deal with the button presses. Two of the NAND gates form a RS flip-flop, and the other two NAND each player’s button with the last LED on the player’s side of the strip. If the player hits the button when their LED is on, the RS flip-flop toggles and changes the decade counter from count up to count down mode. This makes the ball bounce back.
[mischka] finished the project off by putting it in a wooden box and drilling holes for the LEDs, buttons, and a power switch. The final product looks pretty good, and is a great example of how you can use a couple logic chips instead of a microcontroller.
After the break, watch a quick game of monoPong.
Forever.fm is [Peter]’s combination of SoundCloud and The Echo Nest that plays a continuous stream of beat-matched music. The result is a web radio station that just keeps playing.
[Peter] provided a great write up on how he built the app. The server side is Python, using the Tornado web server and Tornadio2 + Socket.IO for handling live updates in the client. To deal with the challenge of streaming audio, he wrote a LAME interface for Python that handles encoding the raw, beat-matched audio into MP3 blocks. These blocks are queued up and sent out to the client by the web server.
Another challenge was choosing songs. Forever.fm takes the “hottest” songs from SoundCloud and creates a graph. Then it finds the shortest path to traverse the entire graph: a Travelling Salesman Problem. The solution used by Forever.fm finds an iterative approximation, then uses that to make a list of tracks. Of course, the resulting music is going to be whatever’s hot on SoundCloud. This may, or may not, match your personal tastes.
There’s a lot of neat stuff here, and [Peter] has open-sourced the code on his github if you’re interested in checking out the details.
