While working towards his Computing and Information Systems degree at the University of London, [Jason Fenech] submitted an interesting proposal for generating random numbers using nothing more exotic than an aquarium and a sufficiently high resolution camera. Not only does his BubbleRNG make a rather relaxing sound while in operation, but according to tools such as ENT, NIST-STS, and DieHard, appears to be a source of true randomness.
If you want to build your own BubbleRNG, all you need is a tank of water and some air pumps to generate the bubbles. A webcam looking down on the surface of the water captures the chaos that ensues when the columns of bubbles generated by each pump collide. In the video after the break [Jason] uses two pumps, but considering they’re cheaper than lava lamps, we’d probably chuck a few more into the mix. To be on the safe side, he mentions that the placement and number of pumps should be arbitrary and not repeated on subsequent installations.
To turn this tiny maelstrom into a source of random numbers, OpenCV is first used to identify the bubbles in the video stream that are between a user-supplied minimum and maximum radius. The software then captures the X and Y coordinates of each bubble, and the resulting values are shuffled around and XOR’d until a stream of random numbers comes out the other end. What you do with this cheap source of infinite improbability is, of course, up to you.
While this project has been floating around (no pun intended) the Internet for a few years now, it seems to have gone largely overlooked, and was only just brought to our attention thanks to a tip from one of our illustrious readers. An excellent reminder that if you see something interesting out there, we’d love to hear about it.
Continue reading “Generating Random Numbers With A Fish Tank”
We’ve seen a lot of unique large-format scrolling message boards on these pages, but most of them use some sort of established technology – LEDs, electromechanical flip-dots, and the like – in new and unusual ways. We’re pretty sure this air-bubble dot matrix display is a first, though.
While it may not be destined for the front of a bus or a train station arrivals and departures board, [jellmeister]’s bubble display shows some pretty creative thinking. It started with a scrap of multiwall polycarbonate roofing – Corotherm is the brand name – of the type to glaze greenhouses and other structures. The parallel tubes are perfect for the display, although individual tubes could certainly be substituted. A plastic end cap was fabricated; air nozzles in each channel were plumbed to an air supply through solenoid valves. An Arduino with a couple of motor driver hats allows pulses of air into each channel to create reasonably legible characters that float up the tube. The video below shows it in use at a Maker Faire, where visitors could bubble up their own messages.
It took some tweaking to get it looking as good as it does, but there’s plenty of room for improvement. We wonder whether colored liquid might help, or perhaps adding a Neopixel or even a laser to each channel to add some contrast. Maybe something to cloud the water slightly would help; increasing the surface tension with a salt solution might make the bubbles more distinct. We doubt it’ll ever have the contrast ratio of a flip-dot display, but it certainly has a charm all its own.
Continue reading “Air Bubble Characters Float Along This Unique Scrolling Display”
Because nothing says “fun for kids” like barbed wire and hypodermic needles, here’s an interactive real-world game that everyone can enjoy. Think of it as a kinder, gentler version of Robot Wars, where the object of the game is to pop the balloon on the other player’s robot before yours get popped. Sounds simple, but the simple games are often the most engaging, and that sure seems to be the case here.
The current incarnation of “Bubble Blast” stems from a project [Niklas Roy] undertook for a festival in Tunisia in 2017. That first version used heavily hacked toy RC cars controlled with arcade joysticks. It was a big hit with the crowd, so [Niklas] built a second version for another festival, and incorporated lessons learned from version 1.0. The new robots are built from scratch from 3D-printed parts. Two motors drive each bot, with remote control provided by a 433-MHz transceiver module. The UI was greatly improved with big trackballs, also scratch built. The game field was expanded and extra obstacles were added, including a barbed wire border as a hazard to the festooned bots. And just for fun, [Niklas] added a bubble machine, also built from scratch.
The game looks like a ton of fun, and seems like one of those things you’ve got to shoo the adults away from so the kids can enjoy it too. But if you need more gore from your robot deathmatch than a limp balloon, here’s a tabletop robot war that’s sure to please.
Continue reading “Balloons And Bubbles Make For Kid-Friendly Robot Deathmatch”
Post an animation on Reddit of a workable machine that looks neat and does something cool and the next day someone will have built it. That’s what happened when [The-Big-Ship] uploaded an animation of a clever bubble making machine — though we had to look twice to convince ourselves that it wasn’t real. The next day [Over_Engineered_2] posted a video of his working one.
We often hear that you need precision CAD software such as Solidworks and AutoCAD to design a functional machine but the animation was done using Cinema 4D, used for films such as Iron Man 3 and Tron: Legacy. This shows that you can at least get a reassurance that the basic mechanics will fit and move together without having to design precision parts.
That’s not to say that reality didn’t interfere with implementing it though. In [Over_Engineered_2]’s video below he points out that the bigger ring of the original animation didn’t work with his small motor and propeller, and had to switch to the smaller ring. Also, note that the ring needed guide rails on the sides to keep it from twisting, something a real world ignoring animation can get away without. Check out the videos below to see the two in action.
Continue reading “How To Turn An Animation Into A Soap Bubble Machine”
If you ever wanted to make an occasion festive with bubbles, [Sandeep_UNO] may have the project for you. As you can see in the video below (and, yes, it should have the phone rotated and it doesn’t), his Arduino uses a servo motor to dip a bubble wand into soap solution and then pulls it in front of a fan. The entire operation repeats over and over again.
There’s not a lot of detail and no code that we could find, but honestly, if you know how to drive a servo motor from an Arduino, the rest is pretty easy to figure out. Look closely at the motion of the robot. What is often accomplished with a spinning wheel of bubble wands and a constant fan becomes much more interesting when applied intermittently. The lazy cadence is what you expect to see from human operation and that adds something to the effect.
We’ve seen faster bubble blowers, but they were not so simple. We’ve even looked at other bubble-blowing robots. If you want to find out more about servo motors in general, our own [Richard Bauguley] has what you need to know.
Continue reading “Arduino Absentmindedly Blows Bubbles”
[Bruce] has created a pretty cool bubble display that is capable of showing recognizable photographs of people. This entire art installation is no slouch at 3-stories tall! This one resides at the Ontario Science Centre in Toronto, Canada. If you are unfamiliar with bubble displays, they consist of several clear vertical tubes filled with a liquid. A pneumatic solenoid valve mounted at the bottom of each tube allows a controlled amount of air to enter the tube at a very specific time. Since the air weighs less than the liquid, the air bubble travels up the tube of liquid. Interesting patterns can be made if these bubbles are timed correctly. This setup uses a Linux-based computer with custom control software to manipulate the valves.
[Bruce] didn’t start off making super-complex bubble displays. This is actually his 3rd go-around and with 96 individual tubes and capable of displaying raster images, it is the most complicated so far. His first creation consisted of 16 tubes, each larger in diameter than the most recent creation. With the larger diameter and less number of tubes came less resolution and the ability to only display simple shapes. Version 2 had twice as many tubes, 32 this time. In addition to doubling the tube quantity [Bruce] also colored the fluid in the tubes, not all the same color but all the colors of the rainbow, from red to violet. Still, this version could not show raster images. It appears to us that the third time’s the charm! Video after the break….
Continue reading “Bubble Displays Are Increasing In Resolution”
Making a bubble display is quite an undertaking, but [Jay] takes advantage of iterative design to construct this impressive (and at 60 tubes, massive) bubble display. The display functions by dispensing bubbles to serve as illuminated pixels in each tube as they rise through the fluid. His build log steps through the display’s construction with a keen attention to detail and above all, patience.
Rather than diving right in and slapping some tubes together, [Jay] took the time to research other bubble display projects, including one we featured a few years back that grew out of yet another HackaDay article. His prototypes started off small to test potential features: whether to use water or glycerin, timing for the air pumps and bubble size, and several others. [Jay] even filled the log with videos of every test, so you can watch the problems and solutions unfold at each step.
The finished display boasts sixty 30″ tall tubes, making it 64″ wide. [Jay] also installed RGB LEDs at every edge where the tubes meet to better distribute the light. You can watch one of the many videos of the display at work below.
Continue reading “An Improved Bubble Display With RGB LEDs”