Marble-elevator dot-matric display

Simple Design Elevates This Mechanical Dot Matrix Display

Don’t get us wrong — we love unique displays as much as anyone. But sometimes we stumble across one that’s so unique that we lack the basic vocabulary to describe it. Such is the case with this marble-raising dot-matrix alphanumeric display. But it’s pretty cool, so we’ll give it a shot.

The core — literally — of [Shinsaku Hiura]’s design is a 3D-printed cylinder with a spiral groove in its outside circumference. The cylinder rotates inside a cage with vertical bars; the bars and the grooves are sized to trap 6-mm AirSoft BBs, which are fed into the groove by a port in the stationary base of the display. BBs are fed into the groove at the right position to form characters, which move upwards as the cylinder rotates. Just watch the video below — it explains it far better than words can.

The clever bit is how the BBs are fed into the groove. Rather than have a separate mechanism to gate the feed port, there’s a backlash mechanism that opens the port when the motor powering the drum runs in reverse for a bit. It’s a clever use of cams to get the job done without adding an extra servo, which sort of reminds us of the design parsimony exhibited in his one-servo seven-segment display.

It’s not clear that this would be a very practical display, but that doesn’t stop it from being cool. Although, [Shinsaku Hiura] just released a follow-up video showing a bigger version of this used to display upcoming events from Google Calendar, so perhaps we’re wrong. Continue reading “Simple Design Elevates This Mechanical Dot Matrix Display”

Mech Warfare: Like Driving A Building-Sized Robot Through A Busy City

The sound a set of machined robot legs tapping on concrete make is remarkable. If for nothing more, the video after the break is worth watching just for this. It’s what caught my attention when I first wandered by the Mech Warfare area at Maker Faire, as one of the competitors had their bot out wandering around as a demo during the setup day.

This is truly a hacker’s robotics competition. There are constraints, but there’s also a lot of room for freedom. Meet a dozen or so requirements and you be as creative as you want with the rest. My favorite part is that this is not a destructive event like many the battle-based robot TV shows that tend to turn my stomach. Instead, these robots each carry an electric AirSoft gun and seek to hit any of four target panels on their competitor’s robot. Continue reading “Mech Warfare: Like Driving A Building-Sized Robot Through A Busy City”

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”

3D Printed Tank Track Pops Together With Plastic BB For Hinge

3D printing is well-suited to cranking out tank tread designs, because the numerous and identical segments required are a great fit for 3D printing’s strengths. The only hitch is the need for fasteners between each of those segments, but [AlwynxJones] has a clever solution that uses plentiful hard plastic spheres (in the form of 6 mm airsoft BBs) as both a fastener and a hinge between each of the 3D printed track segments.

Each segment has hollows made to snugly fit 6 mm BBs (shown as green in the image here) which serve both as fasteners and bearing surfaces. Assembly requires a bit of force to snap everything together, but [AlwynxJones] judges the result worth not having to bother with bolts, wires, or other makeshift fasteners.

Bolts or screws are one option for connecting segments, but those are heavy and can get expensive. Segments of printer filament have been successfully used in other tread designs, though that method requires added work in the form of either pins, or heat deforming the filament ends to form a kind of rivet. This design may be a work in progress, but it seems like a promising and clever approach.

[via Reddit]

Incredible 3D Printed Overwatch Airsoft Pistol

If you ever needed evidence that gamers are some of the most dedicated individuals in all of fandom, then look no further than this fantastic 3D printed recreation of the “Pulse Pistol” as featured in the immensely popular “Overwatch”. Built by the guys at [Danger Doc], this replica doesn’t just look the part, it’s also a fully functional Airsoft gun. In the detailed build video after the break, the year-long design and construction of the gun is broken down for your viewing pleasure.

Because the end goal was to make something that looked as though it came from the game itself, a lot of time was put into making sure that the externals were faithful to the digital version while still able to contain all the hardware they needed to cram in there. This is a fully auto gun, so it needed a battery and motors, as well as a way to feed the firing mechanism Airsoft BBs that didn’t require an anachronistic magazine sticking out.

They combined a off-the-shelf firing mechanism and high-capacity magazine but it took plenty of custom designed parts to get everything mated up. The magazine has a clockwork mechanism to advance the BBs which required the user to manually crank up, but this was replaced with an electric motor to make things a little more futuristic. In addition to all the LEDs on the body of the gun, there’s also an internal array of ultraviolet SMD LEDs to charge the glow-in-the-dark “tracer” BBs as they move through the magazine. In low light, this gives the shots from the gun something of a laser effect.

We’ve seen 3D printed guns from games before, but rarely with this attention to detail and engineering. Honestly, this even gives some real 3D printed guns a run for their money.

Continue reading “Incredible 3D Printed Overwatch Airsoft Pistol”

OpenCV Turret Tracks Motion, Busts Airsoft Pellets

In the eternal struggle for office dominance, the motion-tracking Airsoft/Nerf/whatever, the autonomous turret seems to be the nuclear option. [Aaron] and [Davis] built a motion-tracking turret that uses openCV to detect movement, before hitting a relay to trigger the gun.

There’s a Raspberry Pi controlling a Logitech C210 Pi-compatible webcam, with a stepper hat for the Pi controlling two NEMA steppers that aim the gun. The design is simple but elegant, with a rotating base and an assembly that raises and lowers the weapon.

The openCV intrigues us. We want to see a openCV-powered turret with color detection, so your own team doesn’t get blasted along with your hapless enemies. Or if guarding your cubicle, how about a little openCV facial recognition?

If you want to take a stab at your own, [Aaron] and [Davis] show how they built their project in their page and their Python script can be found on GitHub.  Otherwise, check out the Counter Strike Airsoft robot, the Airsoft sentry gun, and the Nerf turret powered by Slack we published previously. Continue reading “OpenCV Turret Tracks Motion, Busts Airsoft Pellets”

Pen Gun

Pneumatic Pen Gun Is Fit For James Bond

The James Bond franchise is well-known for many things, but perhaps most important to us hackers are the gadgets. Bond always had an awesome gadget that somehow was exactly the thing he needed to get out of a jam. [hw97karbine’s] latest project would fit right into an old Bond flick. He’s managed to build a single-shot pellet gun that looks like a pen.

[hw97karbine] started out by cutting the body from a tube of carbon fiber. He used a hacksaw to do the cutting, and then cleaned up the edges on a lathe. A barrel was cut from a piece of brass tubing with a smaller diameter. These two tubes will eventually sit one inside of the other. A custom front end cap was machined from brass. One end is ribbed and glued into the carbon fiber tube. The barrel is also glued to this end of the front cap, though it’s glued to the inside of the cap. The other end of the cap has 1/8″ BSP threads cut into it in order to allow for attachments.

A rear end cap is machined from Delrin. This piece also has a Delrin piston placed inside. The piston has a small piece of rubber used as a gasket. This piston valve is what allows the gun to operate. The rear cap gets glued into place and attached to a Schrader valve, removed from an automotive tire valve stem.

To pressurize the system, a bicycle pump is attached to the Schrader valve. This pushes the piston up against the barrel, preventing any of the air from escaping. The piston doesn’t make a perfect seal, so air leaks around it and pressurizes the carbon fiber tube. The Schrader valve prevents the air from leaking out of the pen body. A special machined button was threaded onto the Schrader valve. When the button is pressed, the air escapes; the sudden pressure imbalance causes the piston to shoot backwards, opening up a path for the air to escape through the barrel. This escaping air launches the projectile. The whole process is explained better with an animation.

Now, the question left in our mind: is this the same pressure imbalance concept that was used in that vacuum pressure bazooka we saw a couple years back?

Continue reading “Pneumatic Pen Gun Is Fit For James Bond”