Spidery Drone Goes Near-invisible By Spinning Really, Really Fast

July 18, 2026 by Donald Papp 2 Comments

Researchers demonstrate that something interesting happens when a small drone with a spindly airframe spins at a high speed: it very nearly turns invisible. The spidery device is shown mounted in its launcher in the image above. The dark blur at the rightmost side is an outlet on the wall behind the drone, not motion blur from a moving part.

There’s not much to do about the noise, but a high-speed spin becomes nearly invisible.

It’s called the Phantom Twist, and while we’ve seen single-motor drones that spin around a central axis before, they have always incorporated a wing-like structure or cleverly leverage the magnus effect to generate lift.

There’s not a lot of detail about the Phantom Twist’s hardware design but it appears to use a downward-angled motor for lift, relying on a high-speed control system to maneuver and maintain altitude.

This does away with the need for a wing, at the cost of only being stable while rotating at a high speed. We imagine it is also a touchy design that depends greatly on being balanced just so.

A hand launcher spins the device up before releasing it for flight. The visual effect once it is up and running is pretty striking; see for yourself in the short video, embedded just below.

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A scanning-electron micrograph is shown of a cricket's body, focusing on the head, which has been sliced off just above the eyes.

Cross-Sectioning Crickets With A Femtosecond Laser

July 18, 2026 by Aaron Beckendorf 2 Comments

Unlike most cutting lasers, femtosecond lasers don’t vaporize materials; rather, they produce such short, intense bursts of light that the affected region is ablated without having the chance to heat its surroundings. This makes them good at cutting away material without damaging the surroundings, something [Ben Krasnow] exploited to cut cross-sections of samples while still in a scanning-electron microscope.

In this case, the samples were crickets, and before imaging they had to be prepared. First, the bodies were soaked in glutaraldehyde to cross-link the proteins and stabilize the structure. Next, a series of solvent exchanges replaced the water in the bodies with a low-surface-tension solvent; this meant that during the next step, drying, surface tension wouldn’t distort the crickets’ internal structure. Finally, the insect bodies were charred under argon, which made the bodies conductive and more absorptive to laser light.

The laser itself and the scanning galvo are mounted outside the microscope, and shine in through a transparent window. To protect the detector and electron optics from a spray of ablated carbon, a servo motor swings an aluminium shutter between these and the sample while the laser is active. This caused some mysterious problems during testing: after the first ablation run, the electron microscope’s image would contain so much noise as to be unusable, but it would improve over time. As it turned out, the shutter was painted, and the other side of the paint was getting coated with charged carbon particles. This created a small capacitor which disrupted the electron optics as it discharged. Eventually, after solving this and a few other strange problems, [Ben] was able to take several time-lapse videos of the laser gradually ablating a cricket, 30 microns at a time, revealing its inner structure.

Although scanning-electron microscopes are unfortunately shard to come by, it’s still possible to restore a secondhand microscope or, as [Ben] did, build your own. Femtosecond lasers are yet more inaccessible, though they can be used to replicate themselves.

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Flex Filament Stuck To Your Build Platform? Reach For The Isopropanol

July 17, 2026 by Donald Papp No comments

3D printing has been around long enough that everyone’s heard at least one weird trick regarding 3D prints. [Angus] of [Maker’s Muse] puts a few to the test, and came away with one solid tip for releasing TPU from a build platform to which it has unfortunately welded itself.

Flexible filaments tend to stick too well to build plates, which is why an interface layer like a thin layer of glue stick is called for. But what if one forgets to apply it before starting a print job? That can result in a print that is well and truly stuck. Peeling flex filament off a textured PEI bed is a bad time, because the print can tear and tends to leave little bits behind.

[Angus] heard that applying isopropyl alcohol helps release things in that case, so he gives it a try. Lo and behold, it seems to work! See for yourself at 18:10 in the video and keep it in mind if you end up in a similar situation. The print doesn’t exactly fall off on its own, but it does remain in one piece which is more than one can expect otherwise.

Watching isopropyl alcohol help release a stuck print is reminiscent of the way it also removes hot glue from just about any surface. The trick is getting the alcohol to wick in underneath for best results, and the same seems to be true with releasing TPU from a build plate.

One thing to keep in mind when evaluating tips and tricks from over the years is that the landscape changes. Something that maybe seemed to have potential years ago might not make much sense today. A good example is sugar as a bed adhesive, which [Angus] tries out. What started as an experiment in getting PLA to play better with glass build plates years ago doesn’t really carry over to now, with PEI-coated magnetic build platforms pretty much a solved problem. The more likely result nowadays is just a mess.

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Using Solar Air Heating To Dry Clothes

July 17, 2026 by Bryan Cockfield 17 Comments

About a month ago, [Greenhill Forge] built a few solar panels to collect energy from the sun. Unlike solar photovoltaics, which turn sunlight directly into electricity, these were designed to gather solar thermal energy with air. These types of panels can gather a tremendous amount of energy for a very low cost, and although the first video only went into the theory of their operation, his latest video actually shows us how to use that energy in a practical way.

The video starts by building a new solar panel, using upgraded materials and building methods compared to the previous versions which should improve the efficiency. There’s some data analysis of the performance, but at the end of the video [Greenhill Forge] actually hooks one of these up to a clothes dryer to explore its real-world efficacy. This process involves disconnecting the electric heater, removing one of the blower fans, and building a new flange to accept the heated air from the solar panel. A microcontroller keeps an eye on the incoming air temperature and controls a fan to try to hit the target temperature.

After an hour of drying, the test clothing was completely dry, with the only electricity used to turn the drum in the dryer. This is more than an order of magnitude of reduction in the power needed to dry clothes, which is fairly impressive. [Greenhill Forge] also notes that systems like these could augment off-grid systems not only for clothes drying but for home heating, greenhouse heating, or drying out various crops and that they could reduce strain on an electrical system that otherwise relies on resistive heating methods. There are many ways of building these panels, so be sure to check out his first video for ideas. Continue reading “Using Solar Air Heating To Dry Clothes” →

How Octopuses Hacked Their Ribosome To Become Smart

July 17, 2026 by Maya Posch 4 Comments

A fascinating aspect in evolutionary biology is that of convergent evolution — whereby similar structures and functions evolve independently from each other. The highly advanced nervous system of octopuses is a good example here, displaying levels of intelligence and capabilities far beyond those of other cephalopods and matching that of primates, despite no evolutionary link here. Exactly how octopuses developed this rather unique capability remained a mystery, though recent research by [Rishav Mitra] points at the rather unique ribosomes in these animals.

Ribosomes are the molecular machinery at the core of each cell that enable the synthesis of proteins. Due to their highly crucial role, they tend to remain evolutionary unchanged, which makes the big change observed in the octopus (i.e. order Octopoda) in the form of this H88 rRNA break quite remarkable.

Common octopus (<i>Octopus vulgaris</i>). (Credit: Albert Kok, Wikimedia) — Common octopus (*Octopus vulgaris*). (Credit: Albert Kok, Wikimedia)

This H88 break increases the accuracy of translated proteins, something that is essential for complex nervous systems as it reduces cases of misfolded proteins (proteinopathy). Because of how well-preserved ribosomes are across species, the researchers were able to run a number of experiments including a similar rRNA break in E. coli that confirmed many of the assumptions about how these octopus ribosomes performed.

Since proteinopathy results in misfolded proteins that are either useless or harmful to the organism – as seen in various human diseases – this can especially harm long-lived cells like neurons. Unsurprisingly, we can see a similar change to ribosomes in other animal groups, including that of us primates. Although the reasons for octopuses to develop more complex nervous systems wasn’t due to social pressures but rather to cope with highly complex and dynamic environments, it would seem that both types of environmental pressures led to the same convergent path, with a little ribosomal help.

The BornHack 2026 Cyber Ægg Is A Badge With A Life Afterwards

July 17, 2026 by Jenny List 1 Comment

A problem facing the designers of event badges is this: what happens to the badge after the event? It’s one that designers have tried to solve in many ways with varying levels of success, whether that be by making it a dev board, a games console, a mesh-networked communicator, or as in the case of Electromagnetic Field, a continuing badge for future events. Ar BornHack 2026 they have taken a novel approach, by making it a useful desktop appliance. The BornHack Cyber Ægg is a half-egg-shaped badge with a 3D-printed case, and aside from its on-camp applications it’s both a desktop clock/calendar, and a MeshCore node.

Produced with the assistance of the badge.team European badge makers, it’s an egg-shaped PCB with a Nordic nRF52840 at its heart, a Semtech LoRa module, and an e-paper display. On-site there’s a Tamagotchi-style virtual pet game, an event calender, and an RFID token game, but it’s the other two features that give it a life after the camp. The clock and Meshcore, coupled with its case being designed with a flat spot to sit on a desk, make this badge as much an appliance as it is a badge. This is where it will sit in the Hackaday office, and we’re pretty sure most BornHack attendees will use it thus too.

We like this approach to giving a badge a life after the event, and we look forward to seeing what influence it has on future badges. A badge should be a thing to enjoy, not a piece of e-waste.

Hackaday Podcast Episode 378: C Coders, Ceramic Printers, And Shadow Archives

July 17, 2026 by Kristina Panos No comments

It’s a hot one at both microphones, as Elliot Williams and Kristina Panos wilt in the heat with ice lollies and freezer packs. But still, we persevered long enough to make a podcast.

In Hackaday news, Supercon is on! It’s going down in Pasadena, California, but the talks will be somewhere slightly larger, with a courtyard instead of an alley. Get your talk proposals in now! In other Hackaday news, we still have our Frikkin’ Lasers Contest going on until Thursday, July 23rd.

Interestingly enough, we got a comment on an older article from none other than [Michael J. Van de Graaff], whose grandfather invented the Van de Graff generator and was “quite upset” when plans for a DIY version appeared in Scientific American. And finally, Google Earth’s desktop client is being discontinued, but you can still travel the globe on your phone, or in your PC’s browser.

Not only do we have another triple mailbag this week, we have another failed attempt at guessing the Sound by Kristina. However, [Alexander] knew that it was CD-ROM drive a-spinnin’. Speaking of What’s That Sound, be sure to let us know your ideas for the new prize.

That sounds like a lot of preamble, but we quickly get to a full slate of hacks, a couple of which are pretty retro in retrospect. Check out the links below if you want to follow along, and as always, tell us what you think about this episode in the comments!

Download in lovely MP3.