While casually lurking on a famous auction website, [TeddyDesTodes] found the gem shown in the above picture and reverse engineered it. This is a flip dot display, the Brose Vollmatrix compact to be precise. It consists of a grid of small metal discs that are black on one side and yellow on the other, set into a black background. With power applied, the disc flips to show the other side. The disc is attached to an axle which also carries a small permanent magnet. Positioned close to the magnet is a solenoid. By pulsing the solenoid coil with the appropriate electrical polarity, the magnet will align itself with the magnetic field, also turning the disc.
After carrying the 25kg display from his post office to home, [TeddyDesTodes] opened it and discovered that the main control board was using two RS422 transceivers. So he fired up his bus pirate, started to sniff the traffic and noticed that several commands were repeatedly sent. [TeddyDesTodes] stopped the transmission, sent these particular commands and had the good surprise to see some dots flipped. From there, displaying something was a piece of cake.
If this is familiar to you it may be because it was shared in one of the Trinket Contest Updates. But the background details were just so much fun we think this deserves a full feature of it’s own. Do you agree?
[Kevin] has made an interesting camera shutter mechanism using an Arduino and a solenoid. To keep it extremely simple, he is only controlling a single leaf. In the linked video, you can see him take it through its paces from 1/125 seconds up to infinite. This is, of course, a proof of concept, and [Kevin] mentions using smaller components to make everything fit easily inside a Holga-like body. As he points out in the video’s comments, digitally controlling the flash would be a simple matter as well.
A basic camera is incredibly simple to make, and [Kevin’s] design certainly isn’t complicated. That said, if you look at the big picture, [Kevin] is demonstrating how feasible it could be to build an entirely custom camera with a standard microcontroller as the brain. We can’t help but think of all of the possibilities when you are able to control the entire photo taking process.
Interestingly, [Kevin] is also behind this twin lens reflex Kickstarter project from earlier in the year. It will be interesting to see what other camera-related hacks we will see from him.
We’re floored by painter and engineer [Bob Partington’s] graffiti briefcase, which proves how well art and tech can complement one another. Fear not, Arduino haters, [Bob]’s case is an analog dream: no microcontrollers here.
The guts consist of 2 components: a linear drive system and a trigger assembly. The former takes advantage of a small RC motor with a chain drive which slides the can’s mounting unit along two stainless steel rods. The latter includes a custom wound solenoid plugged into a 24V cordless drill battery, which slams down 5 pounds of force onto the can’s nozzle to fire the paint.
This all fits into an otherwise inconspicuous looking briefcase to provide some urban camouflage. The final component is a stencil, which slides into a rectangular hole on the bottom of the case. The paint can sprays downward through the stencil and tags the ground at the touch of a brass button located near the handle. [Bob] has plenty of other cool inventions you should check out that are less illegal. Or, stick it to the man by automating your tagging with Time Writer.
Continue reading “Graffiti briefcase for stealth tagging”
[Vladimir Demin] is somewhat of a legend for us; in his spare time he’s been mastering the automation of musical instruments. This time he’s back with upgrades to his build and four new videos. [Vladimir’s] top priority was to rework the strumming mechanism that earlier ran on solenoids. He’s improved the sound quality and reduced the clicks by swapped to stepper motors and overhauling the software.
Compared to his earlier setup, this one sounds more soulful and less automated, but [Vladimir] admits that it’s still not good enough and that he’s working on a new, brilliant implementation. Until then, take a few minutes and check out the rest of the videos below, then join us in scratching our heads in amazement: everything is built with simple hand tools.
[Vladimir] has come a long way, and it started with this Bayan (button accordion). Last year’s guitar build is also worth a look, as well as an in-depth interview.
Continue reading “[Update] Vladimir’s Robot Guitar”
This hack makes your Keurig experience fully automatic. For those that aren’t familiar with the hardware: this type of coffee maker includes a water reservoir. Coffee is brewed One cup at a time by drawing from that water, quickly heating it, then forcing it through disposable pods containing coffee grounds and a filter. This takes the user-friendly design one step further by automatically keeping the water full.
This goes beyond the last water reservoir hack we saw. That one routed a water line to the machine, but included a manually operated valve. [Eod_punk] added a solenoid valve and level sensor in this project. The level sensor is submerged in the tank and is monitored by a Basic Stamp microcontroller. When the level is low the BS1 drives the solenoid via a transistor, letting the water flow. This is all shown in the video below.
Continue reading “Keurig hack now automatically fills the water reservoir”
We’ve got to say it… these tubular bells sound awful! They don’t really have a tight pitch center so they sound really out of tune to us. But we think that’s the failing of the instrument itself and not the work which [Tolaemon] did to automate the instrument.
There are three main parts to his project. The first, which is shown above, adds a hammer for each bell. The hammers are hinged, with one side being pulled by a solenoid in order to strike the bell. The second part of the hack also uses solenoids, dampening the bell’s ability to ring by pressing a felt pad up against the bottom of the tube. The final portion of the project brings it all home by adding MIDI control to the hardware.
The clip after the break gives a good overview of the different features including some preprogrammed playback as well as direct control of the instrument using an electric keyboard. This reminds us of that scratch-built solenoid xylophone.
Continue reading “Automatic tubular bells given a MIDI interface too”
We admit that this project doesn’t have very many details available, but it was just too neat for us to pass up. It’s a small linear motor which [ligonapProduktion] built after seeing a very brief description of a commercially available version.
The video after the break shows him testing the motor. In this screenshot he’s holding the center shaft while the coil assembly moves back and forth. But it works with a stationary coil moving the rod as well. The motor is basically a modified solenoid. There are sixteen neodymium magnets inside the shaft. The set of four coils is driven by an ATtiny44. Just like a stepper motor, energizing the coils in the correct order pushes against the rare earth magnets creating motion.
We’re not sure if he has any use in mind for this build. For us we just like to see the concept in practice (we feel the same way about a homopolar motor build).
Continue reading “Building a linear motor”