Building A Flying Drone With A Single Propeller

October 17, 2026 by Maya Posch 5 Comments

Technically all that you need in order to make a drone fly is a single motor and single propeller, but realistically it becomes basically impossible to fly it at that point. In the case of helicopters you therefore need a second rotor somewhere to provide counterbalance to the first and to be able to steer.

There are of course a number of ways to make a drone fly with a single propeller, but the compromise usually is to use very large propellers, as well as other mechanisms that make for a very large drone. This wasn’t good enough for [Joshua Bird] who wanted to have a very small, single propeller drone.

Key to making it work is not only a very high RPM, but also a hinged propeller hub that manipulates the angle of the blades in such a way that both pitch and roll can be controlled if you react quickly enough. This turned out to be impossible using standard motor ESCs that do not directly measure the motor’s speed and position but rely on back EMF.

In the final prototype of the drone such details had to be measured directly, with super-fast adjustments to the motor’s speed only possible with custom controller code and a lot of trial and error. Even then the drone would often lose track of its position and crash once more. The solution there was to add an infrared beacon in the room and a sensor on the drone, to give it a fixed reference point.

You can find the project files so far on the GitHub project page, with upcoming changes to the drone design involving improvements like adding a scanner to the drone so that it can autonomously use features in its environment as fixed reference points. That way it might conceivably be able to fly outside as well, which would be quite exciting to see.

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Fairbuds 2 Teardown Shows Little Glue, Easy Battery Swap

October 16, 2026 by Maya Posch 12 Comments

In a world where wireless earbuds are increasingly seen as devices that you toss into the e-waste bin as soon as they stop working, it’s heartening to see companies take the opposite approach with their designs. In a recent teardown of the new Fairbuds 2 by [iFixit] we get a blow-by-blow report of disassembling one of these devices, getting to its rechargeable LIR1054 coin cell, as well as the very accessible PCB should you have to replace a shorted capacitor or similar issue.

Much like with the first version, the 3.6 V lithium-ion coin cell can be extracted simply by pulling on the battery door, which leverages it out of the enclosure. Despite this easy access method and no glue these earbuds are still IP54 rated, so they’re safe to wear when you’re dashing for shelter in a sudden downpour.

To get further into the device, you have to overcome the plastic clips that hold the enclosure together, along with what appears to be a few dabs of glue. Inside it you find the PCB containing the guts, including the Airoha AB1577S, Cortex-M4F-based IC that provides the Bluetooth Low Energy capabilities as well as enabling the touch control and other features.

Below the PCB is the coin cell holder, followed by the only part that saw real glue usage, namely the driver section. Presumably this is the compromise to keep things like sweat out of the device. Even so, after disassembly [iFixit] managed to reassemble the device and the earbud remained in working condition.

The case for the earbuds is even easier to disassemble, using just some bolts to unfasten. The USB-C port is soldered to the PCB which [iFixit] dinged them on, but still gave it a 10/10 on their repairability score.

Compared to Apple’s AirPods this is obviously a whole different world, although recently [iFixit] was somewhat pleased with the most recent AirPods generation being slightly more repairable, with non-destructive entry for a battery swap at least somewhat feasible.

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Disposing Of PLA And Why Composting Is Not An Option

October 16, 2026 by Maya Posch 28 Comments

The ‘biofriendly’ nature of poly(lactic acid) (PLA) filament often gets touted as one of its main advantages over alternatives like PETG, but even a modicum of research ought to inform a person that the biodegrading feature of PLA is only true for pure PLA without additives and at temperatures at or above its glass transition temperature (Tg). Thus the results of a year-long experiment by [I built a thing] shouldn’t be too surprising.

After burying said PLA in the garden like any self-respecting person does who tries to dispose of some evidence, the PLA suffered through a European winter and very hot, dry summer, before being dug up again recently for inspection and testing. Although not the first time that someone has tested this, it’s a good reminder considering just how much PLA filament is used each year.

In total three sample sets were used, one being the control, the other two buried in soil and compost respectively. A visual inspection showed no major difference, and a tensile strength test also showed no statistically significant change among all three sample sets. The experiment could have been concluded here, but instead calorimetry was used in a laboratory setting to see whether exposure to microbes as commonly found in soil does anything significant.

This isothermal microcalorimetry test was performed at the University of Basel, effectively to answer the question whether there’s anything in the PLA samples that can feed said microbes. As it turns out, the answer is a resounding ‘no’, with microbial activity within the presence of PLA dropping off even quicker presumably due to there being less volume available for nutrients.

When [I built a thing] contacted a large number of commercial biodegrading facilities in Switzerland, Germany and the USA, many would happily take PLA, but none of them would accepted 3D-printed PLA parts, which says a lot. The primary reason for this appears to be that even under industrial composting conditions it simply takes too long for these facilities to consider these to be economical to compost.

With PLA primarily degrading via hydrolysis, it needs to be exposed to the right conditions for this process to not take an eternity. You can of course use something like PHA instead, which doesn’t require this hydrolysis step to be biodegradable. Overall PLA is quite a crummy material, with it also suffering from embrittlement due to crystallization that will happily turn a spool of PLA into lots of sad fragments. This makes PETG into a very common and very attractive alternative to PLA.

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Using Optical Waveguide Arrays To Make Sheets Sense Shapes

October 15, 2026 by Maya Posch 9 Comments

Determining the shape of an object which can change dynamically is a bit of a challenge, one that especially vexes those who are really into Virtual Reality. Sensing the orientation of various limbs and appendages usually requires external sensors like cameras, or limit the focus to specific details like just the hands and fingers of the player. A more comprehensive and potentially flexible approach might be possible using optical waveguides, as demonstrated by [Qifan Yu] et al. in a recent article in Advanced Intelligent Systems.

Waveguides are structures that guide electromagnetic waves, with optical waveguides such as used here targeting EM radiation in the optical band. This can even allow for the use of cheap and plentiful optical fiber, though here custom elastomeric waveguides are manufactured. These are laid out onto the sheet in a double-sided, overlapping zig-zag pattern, which allows for easy reconstruction of the shape of said sheet based on how the wave propagation through the waveguide changes.

By characterizing the behavior of the signals through the waveguide, its shape and thus that of the sheet can be reconstructed. This was then demonstrated to be accurate by wrapping the sheet around a volunteer’s arm, elbow and hand, detecting the flexing and movement of individual joints.

Although fairly bulky in the demonstrated configuration and with an unoptimized algorithm, it’s conceivably something that can be miniaturized to the point where it can be woven into regular fabric. This could make for sensor sheets that could track the configuration of everything from robots to human bodies for something like VR purposes.

Linux Kernel Drops AI Tag Requirement, Uses Meta AI For Code Reviews

October 15, 2026 by Maya Posch 98 Comments

Since we last covered the way that the Linux Kernel project has been dealing with the influx of code created using LLM-based coding assistants, all the way back in April, things have changed a lot, with most recently the Linux maintainers deciding to fully drop the requirement to mark LLM-assisted commits with the Assisted-by tag.

While not a fully uncontroversial decision – as also reported by Phoronix – with key maintainers already having made this decision it seems certain to proceed. This is not the only change made fairly recently, with a ‘Sashiko’ bot introduced that is supposed to handle code reviews.

In a July LKML post [Linus Torvalds] defends this decision, with a follow-up post in August by [Jakub Kicinski] it being stated that budget has been secured for using Meta’s LLMs, using said LLM-based resources for reviewing patches, as well as creating and editing commit messages. As noted by [Jakub] they’re running multiple frontier models on each patch to try and weed out confabulations.

Whether this will prove to be the right decision remains to be seen. Whereas most open source projects have firmly banished or heavily curtailed LLM-based contributions on slop, copyright as well as licensing grounds, the Linux Kernel project may be an interesting experiment in what the outcome of the exact opposite approach will be.

Using An ESP32-C3’s RF Hardware For DVB-S2 Video Transmission

October 14, 2026 by Maya Posch 12 Comments

Generally the DVB-S and -S2 standards require a satellite somewhere in Earth orbit to provide a signal to receive, but you can also transmit your own DVB-S2 stream with any RF transmitter if you’re so inclined. Courtesy of recent breakthroughs in using the RF hardware of the ESP32 on a raw level, [SP8ESA] has created the ESP32-DATV project using which you can broadcast a DVB-S2 signal using an ESP32-C3.

While a host PC side application handles the heavy lifting of turning the input video signal into a DVB-S(2) compliant signal, it is the ESP32-C3 that prepares the samples for transmission before sending them off to its RF block, with no external hardware needed.

If this brings to mind the idea of using an off-the-shelf DVB-S2 receiver to play back the signal, the frequency range for DVB-S2 is 10.7 – 12.7 GHz, while the ESP32-C3 is limited to roughly 2.4 GHz courtesy of it targeting only 2.4 GHz Wi-Fi and Bluetooth signals.

Using the ESP32 to transmit is already heating up.

Thanks to [ftg] for the tip.

Using A Waffle To Check The Health Of Your Wii U’s NAND Flash

October 13, 2026 by Maya Posch 14 Comments

Game consoles tend to have a weak spot or two that will take certain units out sooner than they would due to normal parts aging. In the case of the Wii U it’s the eMMC storage IC with the console’s firmware and any user data that likes to keel over, with the SK Hynix variant reportedly developing faulty cells much sooner than the Samsung and Toshiba chips. If you want to check the health of these eMMC ICs in your Wii U, you can do so easily now with the Wafel Installer project by [zer00p].

This doesn’t take much more than navigating to the wafel.xyz URL on the Wii U to launch the installer on any (unmodified) Wii U, or alternatively starting it from an SD card if you’re running a homebrew-enabled console. This can also install the Stroopwafel CFW, ISFSax and the Aroma homebrew environment, but the NAND testing option in the installer’s menu is what you want to select if you’re not into homebrew or have already cracked open the console for said sweet homebrew action.

All of this is covered in this video by [FunkyScott47], whose Wii U’s Samsung-branded eMMC is fortunately still all fine, but it shows off the variety of tests available. Unless the eMMC is already quite cooked this should take only a minute or two, so it’s pretty good for ease of mind.

With the heavily waffle, syrup and stroopwafel-coded naming scheme for these tools we can not be held responsible for a sudden case of the munchies, of course.

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