Designing A Drone To Fire From A Grenade Launcher

You might think that tiny autonomous drones that can be fired out of a standard 40 mm grenade launcher for rapid deployment would be the kind of thing the military would love to get their hands on. Which is true, of course, and a number of companies are working on the idea for police and military applications. But [Glytch] thinks the technology could also be used for search and rescue operations, so he’s working on creating a version for us civilians.

During his presentation “3D Printing Canister-Launchable Drones for City-Scale Wardriving” at the 2019 CircleCityCon, [Glytch] gave an overview of his progress towards creating a small fixed-wing Unmanned Aerial Vehicle (UAV) that can be built even by those of us who don’t have the budgets of a three letter government agency. He’s not at the point where he can do a test launch just yet, but the design is coming along nicely, and we’re extremely interested in seeing where it goes from here.

The only way you’re fitting a winged aircraft into the bore of a 40 mm launcher is by folding it up, and so far, that’s where [Glytch] has directed most of his efforts. The wings of his UAV will use a rigid leading edge that folds flat until deployment. When in flight mode, ripstop nylon attached between the body of the drone and the leading edge will be pulled taught to form the actual wing surface; think of it sort of like a bat’s wing. A similar trick will be used for the two control surfaces at the rear of the craft.

Internally, the UAV is using all off-the-shelf components which [Glytch] hopes will keep it cheap enough that they could eventually be mass produced. As he explained in a recent YouTube video, the motor, speed controller, receiver, and flight controller, are all the sort of thing you’d expect to find in a small RC quadcopter. To make it easier to manage the UAV in the field, the batteries and payload will be housed in a detachable nose cone; allowing the user to rapidly configure the hardware for different missions.

Right now, [Glytch] says the biggest obstacle keeping his drone out of the air is finding a foldable propeller with the specific characteristics he requires. Unable to find anything commercially available, he’s currently looking into designing it himself and having it 3D printed on an SLA machine. He also needs to design a sabot to hold the drone as it travels through the barrel of the launcher. Incidentally, he’s currently testing his design with an Airsoft grenade launcher, as he doesn’t want to wade through the paperwork involved in getting the real deal.

[Glytch] is no stranger to the world of high-tech UAVs. The “Watch Dog” inspired hacking drone he created last year was a huge hit, and he’s recently been working on a HD video and telemetry link over WiFi with the Raspberry Pi Zero for his flying creations.

Continue reading “Designing A Drone To Fire From A Grenade Launcher”

DIY Air Cannon Snags Drones From The Sky

Who hasn’t had the experience of a pesky drone buzzing around that family picnic, or hovering over a suburban backyard where bikini-clad daughters are trying to sunbathe in peace? A shotgun used to suffice for such occasions, but with this compressed-air powered drone catcher, there’s no need to worry about illegally discharging a firearm to secure some privacy.

Before the comment line lights up with outrage, the above scenarios are presented entirely in jest. We do not condone the use of force on a drone, nor do we look favorably on those who use drones in a way that even hints at an invasion of privacy. We can all get along, and even though we hope [Make It Extreme]’s anti-drone gun will never be used in anger, it’s still a neat build that gives us lots of ideas. The rig is essentially four coaxial narrow-bore compressed-air cannons, each launching a slug attached to the corner of a lightweight net. A fairly complex set of linkages sets the spread of the barrels, and a pair of old oxygen tanks serve as reservoirs for the compressed air. A fast-acting dump valve is tripped by an interesting trigger mechanism mounted to a complicated stock and grip; we’d have liked to see more on the fabrication of that bit. The video below shows a test firing that results in a clean takedown of a drone, although we doubt the owner of the quad would characterize it as such.

This build is a bit of a departure from [Make It Extreme]’s usual fare of DIY tools like a shop-built vise or big belt sander, or their unusual vehicles like an off-road hoverboard. But it’s always great to watch a good fabrication video, no matter what the subject.

Continue reading “DIY Air Cannon Snags Drones From The Sky”

Launch Pad For Air-Water Rockets Is Good Clean Fun For STEM Students

We have fond memories of air-water rockets, which were always a dime store purchase for summertime fun in the pool. Despite strict guidance from mom to shoot them only straight up, the first target was invariably a brother or friend on the other side of the pool. No eyes were lost, and it was good clean fun that was mercifully free of educational value during summer break.

But now a teacher has gone and ruined all that by making an air-water rocket launching pad for his STEM students. Just kidding — [Robert Hart] must be the coolest teacher in Australia when Friday launch days roll around. [Mr. Hart] wanted a quick and easy way to safely launch air-water rockets and came up with a pretty clever system. The core task is to pump air into the partially filled water bottle and then release it cleanly. [Robert] uses quick-disconnect fittings, with the female coupling rigged to a motor through a bicycle brake cable. The control box has a compressor, the release motor, and a wireless alarm remote, all powered by a 12-volt battery. With the male coupling glued to the cap of a bottle acting as a nozzle and a quick, clean release, flights are pretty spectacular.

There are many ways to launch an air-water rocket, from the simple to the complex. [Robert]’s build leans toward the complex, but looks robust enough for repeated use and makes the launch process routine so the kids can concentrate on the aerodynamics. Or to just enjoy being outdoors and watching things fly.

Continue reading “Launch Pad For Air-Water Rockets Is Good Clean Fun For STEM Students”

A Grenade Launcher Named RAMBO

Always one to push the envelope, U.S. Army researchers from the U.S. Army Armament Research, Development and Engineering Center (ARDEC) have been successfully experimenting with 3D printing for one of their latest technologies. The result? RAMBO — Rapid Additively Manufactured Ballistic Ordinance — a 40mm grenade launcher. Fitting name, no?

Virtually the entire gun was produced using additive manufacturing while some components — ie: the barrel and receiver — were produced via direct metal laser sintering (DMLS). So, 3D printed rounds fired from a 3D printed launcher with the only conventionally manufactured components being springs and fasteners, all within a six month development time.

Continue reading “A Grenade Launcher Named RAMBO”

A DIY Net Gun To Catch Whatever You Want

Suspicious drones hovering about your property? Burglars or other ne’er-do-well test subjects giving you trouble? Need to catch a dog that keeps meandering through your workshop? [William Osman] suggests you build yourself a pneumatic net gun that can shoot 20-30 feet to catch them all.

The net gun is built largely out of PVC pipe; the air tank — filled via a tire valve — uses adapter fittings to shrink it down to a 1″ sprinkler valve, with an air gun to act as a trigger. The net launcher is made of four lengths of pipe bent with the use of a heat gun — an Occam’s Razor solution compared to his first attempt — and is coupled to the end, while the net loads in using wooden dowels with washers as weights. It won’t trap any large game, but it will certainly net you some fun.

Continue reading “A DIY Net Gun To Catch Whatever You Want”

Shoot Hard Drive Platters Skywards On The Power Of Magnetism

Project Hathor is an electromagnetic ring launcher that launches aluminium hard drive platters 45 feet skywards at the touch of a button. The hard work is done by a bank of capacitors which are charged to 2kV from a microwave oven transformer, before being discharged into a coil of wire on which the hard drive platter is sitting. The resulting burst of magnetic field induces a huge current in the platter, and that current in turn creates an opposing field which launches the ring into the air.

The launcher is the work of [Krux], at the Syn Shop hackerspace in Las Vegas, and he’s made a beautiful job of it. The capacitor bank has ten 3900uF 400V electrolytic capacitors wired as a single 1560uF 2kV capacitor, there are two 225W 2Kohm wire wound discharge resistors, and a beautifully designed home-made high voltage contactor featuring tungsten electrodes. The whole project has been carefully built into an acrylic case for safety, for as [Krux] points out, microwave oven transformers will kill you.

As well as the project web site, there is a YouTube playlist, an image gallery, and a GitHub repository containing all the project’s details. You can see the launcher in action in the video below, launching platters into the Nevada night right on cue.

Continue reading “Shoot Hard Drive Platters Skywards On The Power Of Magnetism”

Your Fingers Will Never Leave Your Hands With This Firecracker Launcher

Who doesn’t like to ring in the New Year with explosives? But speaking from personal experience – I can neither confirm not deny nearly blowing my hand off once with a small dry-ice grenade – a hands-off way to launch your fireworks can be a plus, in which case you might want to check out this automatic firecracker launcher.

[Valentin]’s build has all the earmarks of an inspired afternoon of hasty hacking. Mostly built of wood and hot glue, there’s a feed ramp for fresh ammo and an elastic-powered sled on a ramp. Fireworks are metered onto the sled with one turn of a small gear motor, the fuse is light by a butane torch, and another gear motor pulls the sled back and launches the firecracker. The launch is somewhat anemic – perhaps some stouter rubber bands or latex tubing would provide a little more oomph. But it’s still a fun build with plenty of potential for improvement – perhaps something along the lines of this automated beer catapult?
Continue reading “Your Fingers Will Never Leave Your Hands With This Firecracker Launcher”