Robo Rainbow graffiti machine

[mudlevel] built this rainbow graffiti producing robot for an art exhibit in San Diego. While there are no build details we can easily pick this apart from the pictures. Looks like the brains are an arduino, the drive is a power drill with the trigger removed, and a few other servos for firing the spray cans.  The counter weighted arm for creating the rainbow was a pretty good idea too. Watching this, we had an idea for a super simple purely mechanical way to do this that would be similar to a catapult.  You could use the motion of the trailer to “wind up” the counter balance with a simple ratcheting spool of string attached to the axle. Engage your spray cans and let the balance drop and you’re done.  Pedal on to re-wind the counterbalance for another rainbow.

Have a face for radio?

The help of fellow members of the Austrian technology collective/hackerspace [Otelo] allowed [Georg] to develop a networked audio streaming board, with less than $20 worth of components. Dubbed the OggStreamer for obvious reason, it’s designed to relay audio from a mixing board to an Icecast server (an open source implementation of SHOUTcast) in real-time. The board is based on the STM8 Discovery kit and the Xport Pro. It features stereo input, an onboard OGG Vorbis encoder, and (to top it off) is running uClinux. We think it’s very well thought out - but don’t take our word for it… the OggStreamer won second place last year in the Lantronix XPort Pro Design Contest, and [Georg] has documented it extensively (pdf).

Nokia LCD, nunchuck, and MSP430 join forces

[JB's] driving a Nokia 6100 LCD using an MSP430 with input from a Wii Nunchuck. He’s using the G2211 microprocessor that came with the Launchpad, and developing his code with MSP-GCC. As you can see in the video after the break, this works but there’s some room for improvement. That’s being said, he is bumping up against the code memory limit, with just around 500 bytes left to work with. The LCD screen is SPI and currently it’s hogging the pins that are used for the hardware i2c. Since he needs an i2c bus to talk to the nunchuck he had to go with software i2c which explains part of his program memory troubles.

We’re in no way experts on this, but it seems like he could save space (and improve the input responsiveness) by rewriting his LCD drivers in order to remap the pins. Then again, it might just be better to move up to a larger MSP430. If you’ve got some advice, make sure to share it by leaving a comment.

Continue reading “Nokia LCD, nunchuck, and MSP430 join forces”

TI Evalbot development under Linux

We have some beefs about how Texas Instruments does things, the biggest of which is their lack of support for development under Linux operating systems. But if they build it, someone will try to get Linux involved in one form or another. This time around, [BLuRry] put together a guide to developing for the Evalbot under Linux. He got a shove in the right direction from the code package that went along with that nunchuck-controlled Evalbot. Picking apart that example to the bare essentials he wrote up the process of setting up the cross-compiling toolchain in a virtual machine so as not to clutter your system. From there he details how to set up and use Eclipse when starting a new project. What what did he choose for a Hello World experience? Well a plain “Hello World” was first but right on its heels is the “Hello Hack-A-Day” seen above. So if you’ve got one of these on hand get out there and start coding for it.

Emulating ink cartridges

[Smartie_on_computer] wanted to do some experimenting with an epson printer.  After getting a somewhat disassembled one, the first step was to simply get it running. Unfortunately, one of the ink cartridges was missing and these printers refuse to do pretty much anything without all the cartridges installed.  Rather than go purchase a costly cartridge that they didn’t intend to actually use, [Smartie_on_computer], chose to emulate the cartridge using a microcontroller. After some searching for the protocol used on the cartridge, the info ended up being in the patent. [Smartie_on_computer] now has a functional printer that is destined to be a 3d printer in the near future. You can see a video breakdown after the break.

Continue reading “Emulating ink cartridges”

Digital measuring tape

You’ll never come up short with this measuring tape. That’s because there isn’t actually any tape in the device; it measures distance based on the rotation of a wheel. Roll it across the room and you’ll get an accurate measurement of the distance the little bugger traveled. Like the Etch-a-Sketch from Monday this uses the encoder wheel from a mouse as the input. The IR emitter and sensor from the ubiquitous peripheral find a new home on the PCB that hosts the PIC 16F819. It monitors the rotation, turns it into inches, then spits that number out on a 7 segment display. Handy, and cheap!

Bringing an LCD viewfinder back to life

[Foobarbob] posted a pretty simple job of bringing an LCD viewfinder back to life. He doesn’t specify what was wrong, but since he replaced the backlight, we’re guessing that was the main issue.  It was pulled off of a JVC camcorder. The camcorders with LCD viewfinders are getting more and more common at garage sales, so we’re surprised we don’t see more of these used. [Foobarbob] cracked it open, traced out the power lines and replaced the backlight with an LED and a makeshift diffuser made from a bottle cap. His results look great, we could see this being perfect for an HMD, or possibly a home made VR helmet.