Coilguns used to be the weapons of science fiction. Nowadays, whenever we see someone build one in their workspace it always serves as an inspiring reminder that the future is now. YouTuber [Cody’sLab] has done just that, assembling a rudimentary — but beefy — coilgun in his workshop.
The one in the video is based off an old design that used a 12V battery and without any fancy electronics. This new model has five coil stages along its two-foot length. Four wooden dowels and two copper tubes are arranged in a hexagonal shape to form the barrel and accelerator rails. The coils are each 100 feet of 14-gauge thin coated copper wire, all connected to a common ground. Still lacking any complex electronics, this version eventually gets its projectile launched a good few dozen feet. The ‘bullet’ is a piece of steel with some brass to prevent it spinning in the barrel, while a hole has been drilled in it to accommodate a spring which keeps the two graphite brushes contacting the copper tubes.
The first test proved to be a little underwhelming, and [Cody] had to try something drastic — so he hooked it up to an arc welder to fire the projectile using 22V and 200A.
Continue reading “Five-Stage Coilgun Powered by an Arc Welder!”
This coilgun started as a stock Airsoft rifle. The stock weapon cost about 40€ (just over $50), but we think it was well worth it since it provides plenty of room for all the coilgun components and solves most of the mechanical issues of the build like a body that is comfortable to hold, a trigger, etc.
The clear tube which serves as the barrel (the same setup as we saw in this coilgun guide) is protected by three stainless steel barrels which surround it. They each host a laser diode which results in a Predator-style aiming mechanism that is shown off in the video after the break. There’s even a night vision system that uses IR leds and a viewfinder attached to the stock.
A camera flash is scrapped for the transformer inside. This acts as the voltage generator, charging up a few capacitors. It seems to have no problem generating enough juice to work well, despite the fact that it’s only being powered from two AA batteries mounted in the magazine.
Continue reading “Coilgun with laser sights built in an Airsoft rifle housing”
Coil guns use electromagnetic coils to propel a metal projectile. On the surface they may look rather complicated. But when you break down the concepts it’s pretty easy to learn. If you’ve ever thought of dabbling in this field this lengthy coilgun primer will be a great help.
The basic concept of a coilgun comes in three parts: the coil, the voltage source, and the switch that combines the two. In the build above you can see two spools of wire on the clear barrel of the gun. These make up a pair of accelerators which connect to those huge black capacitors supplying the voltage. The switch they used can’t really be seen but from the article we know it’s a Thyristor; a Silicon Controlled Rectifier (2N6504).
In the video after the break you can see these three parts coming together for a test firing. This is the first step in a longer journey. To achieve higher projectile velocities you must add coils, as in the image above. But spacing and timing quickly complicate the simple concept. But if you can work out all the kinks you end up with some pretty great hardware.
Continue reading “Simple concepts behind complex coilguns”
A few years ago when [Dr. West] was wrapping up his collegiate studies, he put together a pretty cool coilgun for his senior project. The gun was built to simulate the Scorched Earth computer game in real life, but due to time constraints he was only able to build one turret instead of two.
The turret was constructed using mainly salvaged components, most of which came from old laser printers and desktop computers. The turret sits atop a computer PSU, which also happens to be the source of the coilgun’s charging power. A Rabbit 2000 microcontroller is used to drive the gun, which is something we’re familiar with from [Dr. West’s] past projects.
The gun can be aimed manually via the attached keypad, but we prefer the more authentic route, allowing the turret to aim itself after being fed X and Y coordinates. As you can see in the demo video, the coilgun works nicely, allowing [Dr. West] to hit a target from across the room.
We love the concept, and think it would be tons of fun to play a real life game of Scorched Earth with a pair of these turrets. If you are interested in making one of your own, you can find the writeup for his final project here in his public Dropbox.
All we needed to read was 4x 3900uF capacitor bank to know we had yet another decently sized homemade coilgun on our hands. And for the math buffs, that equates out to 1.25kJ of potential energy (efficiency kills it down to 37j of kinetic, but large numbers are more fun) which is more than enough to break skin; of course we recommend you just shoot old electronics rather than friends. On the more technical side, sure its only a single stage for now and we’ve seen some slightly more impressive triple stage guns, but it may just be more beautiful than our previously featured coil pistol. You guys be the judge. Catch a complete video after the jump of the internals and build process, skip ahead to 2:40 for the destruction.
Continue reading “You’ll shoot your eye out, another coilgun”
Remember the coilosapien? I hopped over and found that [marcus] wrote a tutorial on his mini coil gun. He beefed up a disposable camera charging circuit with some extra capacitors to drive the coil, and used a small servo for his automatic reload mechanism. Everything you need to arm your robots.
Being a member of the bomb squad would be pretty high up when it comes to ranking stressful occupations. It also makes for great fun with friends. Keep Talking and Nobody Explodes is a two-player video game where one player attempts to defuse a bomb based on instructions from someone on the other end of a phone. [hephaisto] found the game great fun, but thought it could really benefit from some actual hardware. They set about building a real-life bomb defusal game named BUMM.
The “bomb” itself consists of a Raspberry Pi brain that communicates with a series of modules over a serial bus. The modules consist of a timer, a serial number display, and two “riddle” boxes covered in switches and LEDs. It’s the job of the bomb defuser to describe what they see on the various modules to the remote operator, who reads a manual and relays instructions based on this data back to the defuser. For example, the defuser may report seeing a yellow and green LED lit on the riddle module – the operator will then look this up and instruct the defuser on which switches to set in order to defuse that part of the bomb. It’s the challenge of quickly and accurately communicating in the face of a ticking clock that makes the game fun.
[hephaisto] took this build to Make Rhein-Main 2017, where they were very accepting of a “bomb” being brought onto the premises. The game was setup in a booth with an old analog S-video camera feed and a field telephone for communication – we love the detail touches that really add atmosphere to the gameplay experience.
Overall, it’s a great project that could easily be recreated by any hackerspace looking for something fun to share on community nights. The build files are all available on the project GitHub so it’s easy to see the nuts and bolts of how it works.
We’ve seen builds that bring video games into the real world before – like this coilgun Scorched Earth build. Fantastic.