Category Archives: solenoid

Teardown: Box of Pain (Gom Jabbar Sold Separately)

Posted on by

I immediately felt uncomfortable when I realized this thing is called the “Breo iPalm520 Acupressure Hand Massager”. You’re supposed to stick your hand into it, and through unknown machinations it performs some kind of pressure massage complete with heating action. It’s like one of those pain boxes from Dune. It’s all the more disturbing when you realize the red button on the thing is an emergency release. That’s right, once your hand is in this contraption you can’t take it out until the thing has had its way with you or you tap out.

At least once a week …read more

Continue reading Teardown: Box of Pain (Gom Jabbar Sold Separately)→

Opening A Ford With A Robot and the De Bruijn Sequence

Posted on by

The Ford Securicode, or the keyless-entry keypad available on all models of Ford cars and trucks, first appeared on the 1980 Thunderbird. Even though it’s most commonly seen on the higher-end models, it is available as an option on the Fiesta S — the cheapest car Ford sells in the US — for $95. Doug DeMuro loves it. It’s also a lock, and that means it’s ready to be exploited. Surely, someone can build a robot to crack this lock. Turns out, it’s pretty easy.

The electronics and mechanical part of this build are pretty simple. An acrylic frame holds …read more

Continue reading Opening A Ford With A Robot and the De Bruijn Sequence→

Mechanisms: Solenoids

Posted on by

Since humans first starting playing with electricity, we’ve proven ourselves pretty clever at finding ways to harness that power and turn it into motion. Electric motors of every type move the world, but they are far from the only way to put electricity into motion. When you want continuous rotation, a motor is the way to go. But for simpler on and off applications, where fine control of position is not critical, a solenoid is more like what you need. These electromagnetic devices are found everywhere and they’re next in our series on useful mechanisms.

A Coil and a Plunger

…read more

Continue reading Mechanisms: Solenoids→

Battery-Powered Watering Timer Converted to Solar on the Cheap

Posted on by

Watering the garden or the lawn is one of those springtime chores that is way more appealing early in the season than later. As the growing season grinds along, a chore that seemed life-giving and satisfying becomes, well, just another chore, and plants often suffer for it.

Automating the watering task can be as simple as buying a little electronic timer valve that turns on the flow at the appointed times. [A1ronzo] converted his water hose timer to solar power. Most such timers are very similar, with a solenoid-operated pilot valve in line with the water supply and an electronic …read more

Continue reading Battery-Powered Watering Timer Converted to Solar on the Cheap→

Modified Uke Keeps the Beat with a Solenoid

Posted on by

A classic one-man band generally features a stringed instrument or two, a harmonica in a hands-free holder, and some kind of percussion, usually a bass drum worn like a backpack and maybe some cymbals between the knees. The musician might also knock or tap the sound-boards of stringed instruments percussively with their strumming hand, which is something classical and flamenco guitarists can pull off with surprising range.

The musician usually has to manipulate each instrument manually. When it comes to percussion, [JimRD] has another idea: keep the beat by pounding the soundboard with a solenoid. He built a simple Arduino-driven …read more

Continue reading Modified Uke Keeps the Beat with a Solenoid→

Wind Chimes and Dry Ice Make an Unusual Musical Instrument

Posted on by

When it comes to making music, there are really only a few ways to create the tones needed — pluck something, blow into something, or hit something. But where does that leave this dry-ice powered organ that recreates tunes with wind chimes and blocks of solid CO2?

It turns out this is firmly in the “hit something” camp, as [Leah Edwards] explains of her project. When the metal wind chime tubes come in contact with dry ice, the temperature difference sublimates the solid CO2. The puff of gas lifts the tube slightly, letting it fall back against the brick of …read more

Continue reading Wind Chimes and Dry Ice Make an Unusual Musical Instrument→

Music Box Plays “Still Alive” Thanks to Automated Hole Puncher

Posted on by

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 …read more

Continue reading Music Box Plays “Still Alive” Thanks to Automated Hole Puncher→

Reed Organ MIDI Conversion Tickles All 88 Keys

Posted on by

What did you do in high school? Chances are it wasn’t anywhere near as cool as turning a reed organ into a MIDI device. And even if you managed to pull something like that off, did you do it by mechanically controlling all 88 keys? Didn’t think so.

A reed organ is a keyboard instrument that channels moving air over sets of tuned brass reeds to produce notes. Most are fairly complex affairs with multiple keyboards and extra controls, but the one that [Willem Hillier] scored for free looks almost the same as a piano. Even with the free instrument …read more

Continue reading Reed Organ MIDI Conversion Tickles All 88 Keys→

Early Electromechanical Circuits

Posted on by

In the days before semiconductor diodes, transistors, or even vacuum tubes, mechanical means were used for doing many of the same things. But there’s still plenty of fun to be had in using those mechanical means today, as [Manuel] did recently with his relay computer. This post is a walk through some circuits that used those mechanical solutions before the invention of the more electronic and less mechanical means came along.

Coherer Morse Code Receiver

The circuit shown below is a fun one, especially if you’ve played with crystal radios. It receives Morse code that’s transmitted as bursts of radio …read more

Continue reading Early Electromechanical Circuits→

Robo-Flute Whistles MIDI

Posted on by

We aren’t sure this technically qualifies as music synthesis, but what else do you call a computer playing music? In this case, the computer is a Teensy, and the music comes from a common classroom instrument: a plastic recorder. The mistaken “flute” label comes from the original project. The contraption uses solenoids to operate 3D printed “fingers” and an air pump — this is much easier with a recorder since (unlike a flue) it just needs reasonable air pressure to generate sound.

A Teensy 3.2 programmed using the Teensyduino IDE drives the solenoids. The board reads MIDI command sent over …read more

Continue reading Robo-Flute Whistles MIDI→