An image of a magnetically-suspended Lemming

Mag-Lev Lemming Refuses To Fall

February 19, 2026 by 1 Comment

Are you ready to feel old? Lemmings just turned thirty-five. The famous puzzle game first came out in February of 1991 for the Commodore Amiga, before eventually being ported to just about everything else out there, from the ZX Spectrum to the FM Towns, and other systems so obscure they don’t have the class to start with two letters, like Macintosh and DOS. [RobSmithDev] decided he needed to commemorate the anniversary with a real floating lemming.

The umbrella-equipped lemming is certainly an iconic aspect of the game franchise, so it’s a good pick for a diorama. Some people would have just bought a figurine and hung it with some string, but that’s not going to get your project on Hackaday. [Rob] designed and 3D printed the whole tableau himself, and designed magnetic levitation system with some lemmings-themed effects.

The mag-lev is of the top-down type, where a magnet in the top of the umbrella is pulled against gravity by an electromagnetic coil. There are kits for this sort of thing, but they didn’t quite work for [Rob] so he rolled his own with an Arduino Nano. That allowed him to include luxuries you don’t always get from AliExpress like a thermal sensors.

Our favorite part of the build, though, has to be the sound effects. When the hall effect sensor detects the lemming statue — or, rather, the magnet in its umbrella — it plays the iconic “Let’s Go!” followed by the game’s sound track. If the figurine falls, or when you remove it, you get the “splat” sound, and if the lemming hits the magnet, it screams. [Rob] posted a demo video if you just want to see it in action, but there’s also a full build video that we’ve embedded below.

A commemorative mag-lev seems to be a theme for [Rob] — we featured his 40th anniversary Amiga lamp last year, but that’s hardly all he gets up to. We have also seen functional replicas, this one of a motion tracker from Aliens, and retrotech deep-dives like when he analyzed the magical-seeming tri-format floppy disk.

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Diamond Age-Inspired Pocket Watch Has ESP32 Inside

February 18, 2026 by 3 Comments

A lot of hacks get inspired by science fiction. When that inspiration is taken from the boob tube or the silver screen, the visual design is largely taken care of by the prop department. If, on the other hand, one seeks inspiration from the written word– like [Math Campbell] did for his smart pocket watch inspired by The Diamond Age— the visuals are much more up to the individual hacker. Though no nanotechnology was involved in its creation, we think [Math] nailed the Victorian High-Tech vibe of [Neil Stephenson]’s cult classic.

The build itself is fairly simple: [Math] started with a Waveshare dev board that got him the 1.75″ round touch display, along with an ESP32-S3 and niceties such as a six-axis IMU, an RTC, microphone, speaker, and micro SD card reader. That’s quite the pocket watch! The current firmware, which is available on GitHub, focuses on the obvious use case of a very stylish watch, as well as weather and tidal display. Aside from the dev board, [Math] needed only to supply a battery and a case.

[Math] designed the case for the watch himself in Fusion360 before sending it off to be 3D printed in stainless steel. That might not be molecular-scale manufacturing like in the book, but it’s still amazing you can just do that. Ironically, [Math] is a silversmith and will be recreating the final version of the watch case in sterling silver by hand. We’d be tempted to include a door–making it a “hunter’s case” in pocket watch lingo–to protect that amoled display, but far be it for us to tell an artist how to do his work. If you’re not a silversmith, [Math] has stated his intent to add STLs to the GitHub repo, though they aren’t yet present at time of writing.

We’ve featured smart pocket watches before, some with more modern aesthetics. Of course a watch doesn’t have to be smart to grace these pages.

Thanks to [Math Campbell] for the tip! If you’ve got time on your hands after ticking done on a project, send us a tip and watch for it to appear here.

Taking Photos With Scotch Tape Instead Of A Lens

February 18, 2026 by 2 Comments

Typically, when we want to take images, we use an image sensor paired with some sort of lens assembly to make a picture that’s sharply in focus. However, [okooptics] is here to show us there’s another way—using Scotch tape in place of a typical lens element.

If you just put Scotch tape over an image sensor without a lens, you’ll just get a blurry image, whatever you point it at. With the right algorithms, though, it’s possible to recover an image from that mess, using special “lensless imaging” techniques. In particular, [okooptics] shows how to recreate the so-called coded aperture techniques which were previously demonstrated in [Laura Waller]’s DiffuserCam paper.

It’s complicated stuff, but the video does a great job of breaking down the optics into understandable chunks. Armed with a Raspberry Pi HQ camera covered in a small amount of Scotch and electrical tape, [okooptics] is able to reconstruct a viable image from what initially looks like a blurry mess of nothingness, with the aid of the right deconvolution maths. It’s all about understanding the point spread function of the tape versus a regular lens, and figuring out how to fight off noise when reconstructing the image.

We’ve featured previous work from [okooptics] before, too, like this impressive demonstration of light transport and reconstruction. Video after the break.

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Inside A Dutch Street Organ: The Art Of Mechanical Music-Making

February 18, 2026 by 3 Comments

[James]’ Mechanical Organ of Dutch origin has been around longer than he has, but thanks to being rebuilt over the years and lovingly cared for, it delivers its unique performances just as well as it did back in the day. Even better, we’re treated to a good look at how it works.

The organ produces music by playing notes on embedded instruments, which are themselves operated by air pressure, with note arrangements read off what amounts to a very long punch card. [James] gives a great tour of this fantastic machine, so check it out in the video embedded below along with a couple of its performances.

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Creating The World’s Most Efficient Quadcopter Drone

February 18, 2026 by 5 Comments
Keeping an eye on remaining battery charge. (credit: Luke Maximo Bell, YouTube)
Keeping an eye on remaining battery charge. (credit: Luke Maximo Bell, YouTube)

Although not a typical focus of people who fly quadcopter drones for a hobby or living, endurance flying has a certain appeal to it for the challenge it offers. Thus, as part of his efforts to collect all the world records pertaining to quadcopter drones, [Luke Maximo Bell] has been working on a design that would allow him to beat the record set by SiFly Aviation at 3 hours and 11 minutes.

By using knowledge gained from his PV solar-powered quadcopter, [Luke] set about to take it all a few steps further. The goal was to get as much performance out of a single Watt, which requires careful balancing of weight, power output and many other parameters.

Crucial is that power usage goes up drastically when you increase the RPM of the propellers, ergo massive 40″ propellers were picked to minimize the required RPM to achieve sufficient lift, necessitating a very large, but lightweight frame.

The battery packs are another major factor since they make up so much of the weight. By picking high-density Tattu batteries and stripping these down even more this was optimized for as well, before even the wire gauge of the power wires running to the motors were investigated to not waste a single Watt or gram.

All of this seems to have paid off, as a first serious test flight resulted in a 3 hour, 31 minutes result, making it quite feasible that [Luke] will succeed with his upcoming attempt at the world’s longest flying electric multirotor record. Another ace up his sleeve here is that of forward movement as well as wind provides effectively free lift, massively reducing power usage and possibly putting the 4 hour endurance score within easy reach.

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2026 Hackaday Europe Call For Participation: We Want You!

February 18, 2026 by 5 Comments

Here’s the Hackaday Europe 2026 announcement that you’ve all been waiting for. But wait! This year there’s a twist, or rather two. What absolutely hasn’t changed, though, is that we’d love to see you there, and we’d love to hear about what you’ve been up to, so get your talk or workshop proposal in before March 18th.

New Place, New Time

Hackaday Europe is moving in all four dimensions! We’ll be meeting up in the absolutely lovely Lecco, Italy — just about equidistant from Milan and Bergamot, and taking place May 16th and 17th, with the traditional pre-event meetup on the night of the 15th for those who are already in town. The location is the Politecnico Milano campus, a hub of engineering nestled in the mountains.

Who is going to be speaking at Hackaday Europe? You could be! We’re opening up the Call for Participation right now, both for talks and for workshops. Whether you’ve presented your work live before or not, you’re not likely to find a more appreciative audience for epic hacks, creative constructions, or you own tales of hardware, firmware, or software derring-do.

Workshop space is limited, but if you want to teach a group of ten or so people your favorite techniques, we’d love to hear from you.

All presenters get in free, of course, so firm up what you’d like to share, and get your proposal submitted ASAP.

The Badge

We’ll be bringing the 2025 Hackaday Supercon Communicator Badge with us to Europe, so this is also your chance to get your hands on the retro-styled super sexy keyboard, LoRa module, and fantastically oblong screen. At Supercon, we ran our own custom mesh network, and it worked flawlessly, even on microwatts. We’ll be continuing the experiment in Italy, on different frequencies of course, but maybe pushing some of the transmission parameters to see how far we can go.

The user side of the badge is very accessible as well, being programmed in Micropython and supported with a sweet plug-in architecture that makes adding your own apps a breeze, or at least reasonably straightforward. And when Hackaday Europe comes to a close, you can simply reflash the badge with new firmware, and you’ve got the sweetest Meshtastic device out there.

And it wouldn’t be a Hackaday badge if it weren’t meant to be modified.

The People

The real reason to come to Hackaday Europe, though, is the other folks who come to Hackaday Europe. You’ve never seen a more interested group of hardware hackers, and that’s coincidentally also why you’d like to give a presentation. You get to tell everyone what you’re up to — it’s the ultimate ice-breaker.

At the risk of saying it again: Get your proposal in before March 18th, and we look forward to seeing you on the shore of Lake Como. (Info on tickets and more pre-conference hype coming soon.)

Sliderule Simulator Teaches You How To Do Calculations The Old Fashioned Way

February 18, 2026 by 9 Comments

Ever wanted to know how engineers made their calculations before digital calculators were on every workbench? [Richard Carpenter] and [Robert Wolf] have just the thing—a sliderule simulator that can teach you how to do a whole bunch of complex calculations the old fashioned way!

The simulator is a digital recreation of the Hemmi/Post 1460 Versalog slide rule. This was a particularly capable tool that was sold from 1951 to 1975 and is widely regarded as one of the best slide rules ever made. It can do all kinds of useful calculations for you just by sliding the scales and the cursor appropriately, from square roots to trigonometry to exponents and even multi-stage multiplication and divisions.

You can try the simulator yourself in a full-screen window here. It’s written in JavaScript and runs entirely in the browser. If you’ve never used a slide rule before, you might be lost as you drag the center slide and cursor around. Fear not, though. The simulator actually shows you how to use it. You can tap in an equation, and the simulator will both spit out a list of instructions to perform the calculation and animate it on the slide rule itself. There are even a list of “lessons” and “tests” that will teach you how to use the device and see if you’ve got the techniques down pat. It’s the sort of educational tool that would have been a great boon to budding engineers in the mid-20th century. With that said, most of them managed to figure it out with the paper manuals on their own, anyway.

We’ve featured other guides on how to use this beautiful, if archaic calculation technology, too. We love to see this sort of thing, so don’t hesitate to notify the tipsline if you’ve found a way to bring the slide rule back to relevance in the modern era!

Thanks to [Stephen Walters] for the tip!