Now, we can’t call these LEGO key caps for obvious reasons, but also because they don’t actually work with standard LEGO. But that’s just fine and dandy, because they’re height-adjustable key caps that use the building block principle.
Image by [paper5963] via redditNow you could just as easily build wells as the dome shape pictured here, and I’d really like to see that one of these days.
In the caption of the gallery, [paper5963] mentions foam. As far as I’ve studied the pictures, it seems to be all 3D-printed material. If they were foam, they would likely be porous and would attract and hold all kinds of nastiness. Right?
[paper5963] says that there are various parts that add on to these, not just flat tops. There are slopes and curves, too. They are also designing these for narrow pitch, and say they are planning to release the files. Exciting!
In the early days of AI, a common example program was the hexapawn game. This extremely simplified version of a chess program learned to play with your help. When the computer made a bad move, you’d punish it. However, people quickly realized they could punish good moves to ensure they always won against the computer. Large language models (LLMs) seem to know “everything,” but everything is whatever happens to be on the Internet, seahorse emojis and all. That got [Hayk Grigorian] thinking, so he built TimeCapsule LLM to have AI with only historical data.
Sure, you could tell a modern chatbot to pretend it was in, say, 1875 London and answer accordingly. However, you have to remember that chatbots are statistical in nature, so they could easily slip in modern knowledge. Since TimeCapsule only knows data from 1875 and earlier, it will be happy to tell you that travel to the moon is impossible, for example. If you ask a traditional LLM to roleplay, it will often hint at things you know to be true, but would not have been known by anyone of that particular time period.
Chatting with ChatGPT and telling it that it was a person living in Glasgow in 1200 limited its knowledge somewhat. Yet it was also able to hint about North America and the existence of the atom. Granted, the Norse apparently found North America around the year 1000, and Democritus wrote about indivisible matter in the fifth century. But that knowledge would not have been widespread among common people in the year 1200. Training on period texts would surely give a better representation of a historical person.
The model uses texts from 1800 to 1875 published in London. In total, there is about 90 GB of text files in the training corpus. Is this practical? There is academic interest in recreating period-accurate models to study history. Some also see it as a way to track both biases of the period and contrast them with biases found in data today. Of course, unlike the Internet, surviving documents from the 1800s are less likely to have trivialities in them, so it isn’t clear just how accurate a model like this would be for that sort of purpose.
The BBC recently published an exposé revealing that some Chinese subscription sites charge for access to their network of hundreds of hidden cameras in hotel rooms. Of course, this is presumably without the consent of the hotel management and probably isn’t specifically a problem in China. After all, cameras can now be very tiny, so it is extremely easy to rent a hotel room or a vacation rental and bug it. This is illegal, China has laws against spy cameras, and hotels are required to check for them, the BBC notes. However, there is a problem: At least one camera found didn’t show up on conventional camera detectors. So we wanted to ask you, Hackaday: How do you detect hidden cameras?
How it Works
Commercial detectors typically use one of two techniques. It is easy to scan for RF signals, and if the camera is emitting WiFi or another frequency you expect cameras to use, that works. But it also misses plenty. A camera might be hardwired, for example. Or store data on an SD card for later. If you have a camera that transmits on a strange frequency, you won’t find it. Or you could hide the camera near something else that transmits. So if your scanner shows a lot of RF around a WiFi router, you won’t be able to figure out that it is actually the router and a small camera.
Sometimes you just know that you have the best ever idea for a hardware product, to the point that you’re willing to quit your job and make said product a reality. If only you can get the product and its brilliance to people, it would really brighten up their lives. This was the starry-eyed vision that [Simon Berens] started out with in January of 2025, when he set up a Kickstarter campaign for the World’s Brightest Lamp.
When your product starts shipping and you hope everything went right. (Credit: Simon Berens)
At 50,000 lumens this LED-based lamp would indeed bring the Sun into one’s home, and crowdfunding money poured in, leaving [Simon] scrambling to get the first five-hundred units manufactured. Since it was ‘just a lamp’, how hard could it possibly be? As it turns out, ‘design for manufacturing’ isn’t just a catchy phrase, but the harsh reality of where countless well-intended designs go to die.
The first scramble was to raise the lumens output from the prototype’s 39K to a slight overshot at 60K, after which a Chinese manufacturer was handed the design files. This manufacturer had to create among other things the die casting molds for the heatsinks before production could even commence. Along with the horror show of massive US import taxes suddenly appearing in April, [Simon] noticed during his visit to the Chinese factory that due to miscommunication the heatsink was completely wrong.
Months of communication and repeated trips to the factory follow after this, but then the first units ship out, only for users to start reporting issues with the control knobs ‘scraping’. This was due to an issue with tolerances not being marked in the CNC drawings. Fortunately the factory was able to rework this issue within a few days, only for users to then report issues with the internal cable length, also due to this not having been specified explicitly.
All of these issues are very common in manufacturing, and as [Simon] learned the hard way, it’s crucial to do as much planning and communication with the manufacturer and suppliers beforehand. It’s also crucial to specify every single part of the design, down to the last millimeter of length, thickness, diameter, tolerance and powder coating layers, along with colors, materials, etc. ad nauseam. It’s hard to add too many details to design files, but very easy to specify too little.
Ultimately a lot of things did go right for [Simon], making it a successful crowdfunding campaign, but there were absolutely many things that could have saved him a lot of time, effort, lost sleep, and general stress.
As anyone who extrudes plastic noodles knows, the glass transition temperature of a material is a bit misleading; polymers gradually transition between a glass and a liquid across a range of temperatures, and calling any particular point in that range the glass transition temperature is a bit arbitrary. As a general rule, the shorter the glass transition range is, the weaker it is in the glassy state, and vice-versa. A surprising demonstration of this is provided by compleximers, a class of polymers recently discovered by researchers from Wageningen University, and the first organic polymers known to form strong ionic glasses (open-access article).
When a material transforms from a glass — a hard, non-ordered solid — to a liquid, it goes through various relaxation processes. Alpha relaxations are molecular rearrangements, and are the main relaxation process involved in melting. The progress of alpha relaxation can be described by the Kohlrausch-Williams-Watts equation, which can be exponential or non-exponential. The closer the formula for a given material is to being exponential, the more uniformly its molecules relax, which leads to a gradual glass transition and a strong glass. In this case, however, the ionic compleximers were highly non-exponential, but nevertheless had long transition ranges and formed strong glasses.
The compleximers themselves are based on acrylate and methacrylate backbones modified with ionic groups. To prevent water from infiltrating the structure and altering its properties, it was also modified with hydrophobic groups. The final glass was solvent-resistant and easy to process, with a glass transition range of more than 60 °C, but was still strong at room temperature. As the researchers demonstrated, it can be softened with a hot air gun and reshaped, after which it cools into a hard, non-malleable solid.
The authors note that these are the first known organic molecules to form strong glasses stabilized by ionic interactions, and it’s still not clear what uses there may be for such materials, though they hope that compleximers could be used to make more easily-repairable objects. The interesting glass-transition process of compleximers makes us wonder whether their material aging may be reversible.
While the average person would use a standard charger to top off their phone, [Tom Stanton] is no average man. Instead, he put mind to matter with an entire pendulum battery system.
Using the inductive effects of magnets on copper coils, [Tom] found the ability to power small components. With that in mind, the only path was forward with a much larger pendulum. A simple diode rectifier and capacitors allow for a smoother voltage output. The scale of the device is still too small to power anything insane, even the phone charging test is difficult. One thing the device can do is juice up the electromagnetic launcher he put together a couple years back to hurl an RC plane into the air.
The useful applications of pendulum power storage might not be found in nationwide infrastructure, but the application on this scale is certainly a fun demonstration. [Tom] has a particular fascination with similar projects where practical application comes second to novelty. For a perfect example of this, check out his work with air powered planes!
One of the constants in consumer electronics is that designers will try to put as many features into a single device as possible, whether it’s a Walkman with a radio tuner or a new class of devices that crams a photo and video camera in the same enclosure as a music player. At the time that the Kodak MC3 was released this made it a rather unique device, with it in hindsight being basically a smartphone without the phone, as [Tech Tangents] aptly notes in his recent video on the device.
Six years before Apple’s iPhone would be announced, and eight years before the first iPod with a video camera, the Kodak MC3 was in many respects bleeding edge technology targeted straight at tech enthusiasts. For less than $300 you got VGA-quality images, CompactFlash storage, and MP3 playback capability. The videos it produced were 320×240 resolution, h.263 encoded MOVs with a maximum length of 4 seconds at 20 FPS, or 4 minutes with a 64 MB CF card.
The unit that [Tech Tangents] got used came with a 128 MB CF card, but couldn’t use a 2 GB CF card, which is a shame. The screen on it got a lot of flak for not not having a backlight, but this was common for the era, as were the poor viewing angles. Ditto for the poor video quality, as anyone who invested in consumer digital cameras in the early 2000s can attest to. In that respect this Kodak device was probably a bit too ambitious with its features for the era, maybe to compensate for it completely missing the boat on the rise of digital camera technology around the time.
