TechyMagThings

Like many people who read Hackaday, we are fairly fluent in a number of computer languages, but we have to admit it is easier to pick up languages that look like they group with things like Fortran. Sure, modern languages have all sorts of features, but the idea that you have a text file that executes in some order, variables, statements, and so on runs through most popular languages, but not all of them. Lisp and its variants are a different way of looking at things. And then there’s Prolog. [Alexander Petros] has an interesting way of explaining Prolog as a Pokémon game.

Prolog was “the next big thing” when AI meant expert systems. It is more of a specialized database where you define facts and rules that the computer can infer answers to queries. For example, if the facts say that Paul and Anna both have Mary as a parent, and a rule says that people with the same parent are siblings, then a query asking whether Paul and Anna are siblings will indicate that they are.

How does this relate to Pokémon? The classic card game pits teams of different characters against each other, and each has particular traits and moves. Prolog is well-suited to expressing situations like this, where there are many facts and rules about how they relate to one another.

In the example, characters like Bulbasaur and Squirtle are known to be pokemon. Each character can have one or more types (e.g., Bulbasaur is both a grass and poison type). Then, rules can define things like the types of moves and traits each character has. The way Prolog works, you can provide a variable as part of a query and get lists of matches, much like a database.

We didn’t see [Alex] mention the cut operator, and many people do not like to use it. There are probably other parts of Prolog left out, too, like backtracking. However, this is as good a place to start as any, and the example is exactly the sort of problem that Prolog is good at.

If you really prefer C, you can mix C and Prolog. We can’t imagine how it worked, but there was even a computer with a Prolog operating system.

Electroplating 3D prints is a good way to get a pretty nice coating on even a basic PLA part, but generally you’re expected to dunk the entire part into a big vat with electrolyte after coating it with the requisite conductive paint layer. This is great for small parts, like a ring you’d put on a finger, but gets rather silly when it’s a much larger part, such as the one in [Hendrik]’s recent video. Out of curiosity he tried to see whether rotating the part through a much smaller vat would still get you an even coating, or not.

Perhaps ironically this process required building a custom vat out of acrylic, as well as an entire rig to hold up the part and gently rotate it. This highlights the main disadvantage of this approach, in that unless you’re doing a small production run or otherwise get to re-use the rig a lot it’s a lot of extra effort.

That said, the rotation is controlled by an ESP32 and a stepper motor along with a requisite stepper driver, with the most exotic part being the whole custom PCB and enclosure, all of which can be used repeatedly. With all of that tested and confirmed working, the part to be plated was sanded, sprayed with conductive paint and hooked up to the rotating rig for an overnight run.

Following that the part’s new copper coating was polished before more layers of electroplating were applied to get the desired two different colors from different metals. Along the way no issues were found with this method of rotating electroplating, so if you regularly struggle with oversized parts to electroplate, this would seem to be a viable method.

You could make a clock with three hands spinning about nested central shafts. If you did that, we probably wouldn’t publish it on Hackaday unless you really found a way to make it interesting. Make a clock out of voltmeters, however, and that usually catches our eye. [lcamtuf] has done just that.

The heart of the build is an AVR128DB28 microcontroller, an 8-bit microcontroller that is still currently in production. It runs at 8MHz, and drives a series of three Baomain 65C5 voltmeters to display hours, minutes, and seconds. Each has a custom printed face with the correct number of 13 or 61 divisions as needed. The voltmeters are driven by a continuous stream of 1-bit pulses with a software-controlled duty cycle determining exactly how far the needle moves. Yes, it’s using simple pulse width modulation, coded by hand by [lcamtuf] to do the job. All the components are wrapped up in a beautiful wooden case, with delicately kerf-bent panels to create the attractive curved lines.

We’ve featured similar builds before, too. As it turns out, hackers just really love clocks and old-school dials. Video after the break, which is worth watching for the rollover behaviour alone.

Most consumer-grade night vision devices are basically a standard camera without the usual filter to block near infrared (NIR) light, which are then paired with a NIR light source that’s not visible to the human eye. Unlike the passive night vision provided by a photomultiplier tube, these can’t resolve objects beyond the beam of their illumination source. On the other hand, if, as [Project 326] did, you use an infrared laser to illuminate the scene, you can still get a very long range out of these devices.

[Project 326]’s device consists of a previously-built reflecting telescope focusing a distant scene in to a webcam with the infrared filter removed, with the infrared laser illuminating the scene. Finding a suitable laser took some effort: the first option, a secondhand fiber-coupled industrial laser, was accidentally over-volted and destroyed during testing. The second had a fiber output which proved extremely hard to terminate, and a third laser couldn’t be collimated correctly. The final laser was a Vertical-Cavity Surface-Emitting Laser (VSEL) diode array element driven at about two Watts and collimated by a small lens.

This illumination setup is safe at a long range, but only at a long range. The laser was strong enough to burn cardboard at close range, but out at about 500 meters, the beam had spread until it was less than a hundredth of the standard safety limit. To make sure that nothing else would get in the way of the beam, it was shone down from the top of a tall building. Testing with a power meter also showed that at a long range, the beam was weaker than expected. It turned out that the wavelength used (940 nm) is attenuated by water vapor, to the point that up to 70% of the beam’s strength was lost before reaching the target. Despite this, and despite a rather linear beam profile, a somewhat dark image was still visible at 650 meters.

If you’re looking for a somewhat more versatile long-range night vision device, check out one based on a photomultiplier tube. Another approach is to use a very high-sensitivity camera.

Thanks to [Keith Olson] for the tip!

If you’ve got a Bambu Labs printer, it’s usually pretty straightforward to keep an eye on it via the onboard display or the various apps the company has released. However, if you want a dedicated display somewhere remote from your printer, you might like this build from [Keralots].

The project is based on an ESP32-S3 Super Mini, paired with a 1.54″ TFT display with a 240 x 240 resolution. It’s set up to talk to Bambu Labs printers over MQTT with TLS. It harvests status data and uses it to display a real-time dashboard with critical printer parameters display on arc gauges. There’s also plenty of live stats to pore over, as well as buzzer notifications if you want auditory alerts about what is going on. It’s possible to use with just about any Bambu Labs printer with a Bambu Cloud access token; otherwise, you can tinker with LAN Direct connections on certain models, but you might need to enable Developer Mode depending on your rig.

If you want to monitor your printer’s vital statistics at a glance, this project is a great way to do it. It breaks out the fundamental numbers in a clear and obvious fashion that’s a little easier to parse quickly compared to the interface of the official software. We’ve featured similar builds before, too. If you’re also paranoid about prints and using that to motivate you towards creating useful hardware, don’t hesitate to let us know on the tipsline. 

Sure, you can buy a portable monitor off your favorite e-tailer, but with perfectly fine displays in devices like laptops being tossed out every single day, why not repurpose those instead? That’s what [ScuffedBits] recently did with the panels  pulled from some old laptops.

A good question with any such salvaged panel is just how practical it is to still use them, with disqualifying features being things like passive-matrix TFTs as well as the use of CCFL backlighting as with one of the three panels demonstrated in the video.

Looking up the model number of a panel on a site like panelook.com will tell you the display technology, resolution and other important details before you decide to commit to using it. If it’s using a LED backlight and at least Low-Voltage Differential Signaling (LVDS) but ideally eDP you can likely find a cheap driver board for it that has all the requisite inputs like HDMI and power.

The hardest part is probably the case for the panel, as they’re rather thin and fragile. Here [ScuffedBits] opted to 3D print two different types of cases, with the second variant probably being the best version as it protects most of the panel. Installing these is quite easy: slide the panel into the first half, then add the second half of the case to close it up. Permanently keeping the case in place was left as an exercise to a future [ScuffedBits], while demonstrating why it’s definitely the hardest part of repurposing an old laptop display.

To start things off, we’d like to extend a special thanks to everyone who joined us for Hackaday Europe this weekend in Lecco, Italy. It was 48 hours of fascinating talks, incredible badge hacks, and some of the greatest company you could hope for. For those who couldn’t make it in person, we didn’t forget you — expect to hear more about what went down once we get a chance to catch our collective breath.

That’s not the only thing to keep an eye out for in the coming days. This is your reminder that Amazon will be officially ending support for older Kindles in a few days. After May 20th, any of the megacorp’s e-readers that were introduced before 2012 will be persona non grata, so you should plan accordingly.

The biggest change is that these older devices won’t be able to buy digital books from Amazon, but you can still use them offline, and the fantastic Calibre makes it a breeze to load up content from other sources. To be perfectly honest, we’d advise any Kindle user to decouple their device from the Amazon mothership by using Calibre or even jailbreaking it and installing KOReader, so the end of official support is fine by us. In fact, if a surge of unsupported Kindles brings more attention and users to those projects, that suits us just fine.

We’ve also heard that Microsoft is removing the “Together” feature from Teams on June 30th. We actually had to look this one up — apparently, it was a mode added during the pandemic that made it look like you and the other people in the call were all sitting together in a virtual conference room of sorts. Sounds an awful lot like a dystopian nightmare to us, but to be fair, things got kinda weird there when we were all sheltering in place, so it’s hard to judge. In any event, we don’t think too many people will miss this particular feature in 2026.

While on the subject of products the world seems to have forgotten about, Electrek reports that Tesla has all but given up on their once promising solar roof tiles. The company won’t say just how many installations they’ve completed since the camouflaged panels hit the market in 2016, but estimates suggest the number may be as low as 3,000. It will probably come as little surprise to find that cost seems to be the biggest factor: a roof full of Tesla’s swanky tiles could run you six-figures, while traditional panels are only getting cheaper every year.

From end-of-life to the latest and greatest, today also marks the release of Linux 7.1-rc4. If you’re in the business of running release candidate kernels, you probably don’t need to be told what’s new, but for everyone else, Phoronix has a rundown on some of the changes. Highlights include improvements to hardware support (including a fix for the Framework Laptop 13 Pro), security fixes, and new guidance about the use of AI-generated code.

Finally, if you want a time-waster, there’s Halupedia. According to the site’s GitHub: An infinite, hallucinated encyclopedia. Every link leads to an entry that does not exist yet — until you click it, at which point an LLM pretends it has always existed and writes it for you, in the deadpan register of a 19th-century scholarly press. For example, you can read about “The Ministry of Slightly Wrong Maps,” or, if you prefer, “The Ministry of Terribly Wrong Maps.”

See something interesting that you think would be a good fit for our weekly Links column? Drop us a line, we’d love to hear about it.