Creating Beautiful Light Shows With Soap

June 19, 2026 by Zoe Skyforest 14 Comments

We feature a lot of fun projects with LEDs and lasers and all kinds of light effects going on. Most of these are very digital. However, there are a great many ways to make beautiful lighting effects without ones and zeros. The Maelstrom Lamp from [Michele Lorenzi] is a great example of that.

*The Maelstrom Lamp is externally decorated to indicate its function.*

The concept is decidedly old-school. The lamp uses a delicate, thin soap film stretched across an aperture as its primary optical element. The varying thickness of the film across its surface leads to constructive and destructive interference when white light passes through it. This creates a kaleidoscope of color; the same effect you might have seen when an oil slick forms in a dirty puddle.

In this case, though, that effect is projected with the aid of a powerful 800-lumen flashlight and some supporting optics. [Michele]’s write-up does a great job of explaining the finer design details that maximize the vibrancy of the effect, from the waviness in the gasket that supports the soap film, to the optics that focus the torch beam.

If you’re looking for some suitably psychedelic lighting effects for your next house party, you really ought to build one of these. We’ve featured some other fun classic lighting effects before, like these wonderful bubble lamps. Continue reading “Creating Beautiful Light Shows With Soap” →

The Uncooperative Mirror Will Not Help You

May 30, 2026 by Jenny List 7 Comments

The value of a mirror is in its clarity. If the reflection is cast by [danicakostic17]’s Uncooperative Mirror though, you’ll find anything but. It’s described as a useless machine, because it appears as a tiled mirror. As you approach it though, the tiles shake around and make it very difficult to follow what’s in front of you. It’s an art piece and a prank all in one, and we like it.

Behind the mirror is a 3D printed frame and a set of small servos with what look like some belts to hitch them up. There’s an ultrasonic sensor and an Arduino Uno, that sets those servos going as soon as the ultrasonic sensor sees anything. We can see this thing would be fun at a party.

Everything you’ll need is on the Instructables page linked above should you be foolhardy enough to want your own, and there’s even a YouTube video which we’ve placed below.

Continue reading “The Uncooperative Mirror Will Not Help You” →

Drawing Videos On An Etch-a-Sketch

May 26, 2026 by Julian Scheffers 2 Comments

We’ve covered etch-a-sketch robots before, but usually they’re not quite as fast as [Every Flavor of Robot]’s “video” etch-a-sketch, capable of drawing a full portrait in as little as a minute.

The robot, nearly finished drawing a portrait of [William Osman]

The idea comes from the motivation to make something cool for Open Sauce. Of course, most projects with a deadline come very close to missing it, and–like many an Open Sauce project–this one is no exception. Arriving in California, they realize they couldn’t access their code! Fortunately, they get a demo working where your portrait is drawn just in time.
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Slightly Sentient D20 Might Subtly Shift Your Rolls

May 25, 2026 by Donald Papp 2 Comments

A twenty-sided die (d20) is a common thing in tabletop gaming, and [kati]’s slightly sentient d20 is a PCB that not only delivers random results on demand, but responds to hot and cold streaks and may even tweak the results a little to reflect its mood.

On its face the unit is a touch-sensitive PCB with twenty small charlieplexed LEDs around its perimeter, one for each die result. When activated by a touch on the center pad, the die dutifully animates a die roll and delivers a result. But something happens if the RNG (random number generator) coughs up results that are unusually lucky, or unlucky.

After a streak of natural 1s, the device gets cranky. It begins to ignore the occasional activation input, and may glitch before a roll, reflecting a low mood. In addition, future rolls while in a low mood have a slight chance of being silently discarded and re-rolled into a low range (1-6), prolonging the unlucky streak. The inverse is true of a die that encounters a lucky run of natural 20s, with the die’s mood shifting to high spirits and having a slight chance of re-rolling future results into a high range (16-20).

The idea is to create (and feed) the feeling of lucky and unlucky streaks. Gamers are of course perfectly capable of projecting such feelings all on their own, which means the die acts as both mirror and amplifier of these emotions. In addition, each die acts slightly differently as a result of being imprinted with different RNG seeds, timing values, and response times which makes each one feel unique. There are reportedly other hidden features as well.

If you’d like to try making your own, keep an eye on the GitHub repository. The originals have design elements that were heavily personalized for [kati]’s gaming group, so the design files are in the process of being turned into a meaningful public release. Of course, there’s more than enough detail already to roll your own if you are so inclined.

Adorable ASCII Aquarium Lives On Your Desk

May 24, 2026 by Donald Papp 26 Comments

[Kert Gartner]’s ASCII Aquarium turns a cheap yellow display (CYD) into a tiny simulated aquarium, complete with ASCII sea creatures each with their own behaviors. There’s all kinds of options and even timekeeping functionality, so the miniature water world can also pull its weight as a desk clock.

The fish and other animal movements are not a series of canned animations; each creature has its own behaviors and responses to things like feeding, which is accomplished by tapping on the screen. A hidden menu offers a wide range of configuration and display options, and there’s even an option to export screen contents as bitmaps.

Add a 3D-printed enclosure and the whole thing looks like a pretty nice weekend project. There’s even a display flip mode, just in case you have a spare 50 mm beamsplitter kicking around.

It’s a very clever use of a CYD that shows how good color and graphics can look when one designs with the hardware’s capabilities (and limitations) in mind.

The CYD is an ESP32-based development board with integrated touchscreen display, and is known for its affordable price and wide availability. This one would look great next to a CYD electric jellyfish.

PenPal, A Robotic Drawing Assistant

April 25, 2026 by Bryan Cockfield 11 Comments

Emergent properties include examples like murmurations of starlings which can’t be predicted from looking at a single bird, weather which can’t be predicted by looking at a few air molecules, and consciousness which can’t be predicted by looking at a neuron. Likewise, when adding a new tool to a workflow, emergent properties can show up as well. A group at Chicago University developed a robotic drawing tool and a few artists developed some unique drawing methods using it.

The robotic pen uses a pair of tendons to extend the working end out a certain amount. From there it uses a set of servos to can be programmed to revolve around in a defined path, making repeating movements while the artist makes larger movements over the paper. Originally meant for shading, small circles or simpler back-and-forth movements were preset, but with full control over the pen’s behavior the artist can shift focus away to other tasks within the creative process. A study with ten participants was done which showed artists coming up with novel ways of using a tool like this, and others reporting that it’s almost like drawing together with another person.

Looking for novel ways that humans can interact with computers and robots can often lead to surprising outcomes like this. Members of this group aren’t new to novel human interface devices either; they’ve also built a squishy dynamic button as well.

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The Complex Transformations Underlying MC Escher’s Works

April 12, 2026 by Maya Posch 12 Comments

Self-similar images are rather common, which are images in which the same image is repeated on a smaller scale somewhere within the image that one is looking at, something which is also referred to as the Droste effect. Yet in [MC Escher]’s 1956 Prentententoonstelling (‘picture gallery’) drawing, this self-similar image is somehow also the foreground image, from where it just keeps looping around in an endless dance. How this effect is accomplished and what the mathematical transformations behind it are and how they work is explained in a recent video by [3Blue1Brown].

The video uses previous work by [B. de Smit] and [H. W. Lenstra Jr] whose 2003 paper detailed the underlying transformations, as well as the mystery of the center of the work.

Although [MC Escher] created a transformation grid with square rectangles into which a non-transformed image could be copied verbatim, he left the center as a void with just his signature in it, leaving many to guess how one might be able to fill in this area with something that made sense. In the work by [Smit] et al. it was postulated that by treating the work as having been drawn on an elliptic curve over a field of complex numbers this might be possible.

While the transformation is simple enough at first, with just four rectangles at different zoom levels to make up the corners, the trick is to connect these rectangles. Using the demonstrated complex method this can be automated, with the central void now filled in and creating its own Droste effect. This once again demonstrates the beautifully complex mathematics in [Escher]’s works, despite him never having had any formal mathematical education.

Continue reading “The Complex Transformations Underlying MC Escher’s Works” →