Mysterious Files PH

As simple as the concept of adding two numbers appears at first glance, doing it in the 1970s in Intel’s 8087 FPU with its 69-bit adder was still a tall order. This is namely the core feature that many features like tangents, cosines and exponentiation rely on, so it had to be basically perfect. In a recent die-level analysis of the 8087 [Ken Shirrif] dives into the structure, layout and functioning of this ‘beating heart’ of this piece of semiconductor history.

Although anyone can build a simple binary adder out of off-the-shelf parts including 74-series logic ICs, the problem is to make it fast so that the 69th bit doesn’t have to wait for e.g. a carry to trickle all the way through the preceding bits. The main way that this is solved is by breaking addition into 4-bit blocks, reducing the problem by a factor of four, along with an optimized Manchester carry-chain carry-lookahead implementation.

The main advantage of this variation of a carry-lookahead is that it reduces the number of required transistors, without sacrificing too much performance. Later on Intel would switch to the faster, but more transistor-intensive Kogge-Stone adder.

Implementing this entire adder with NMOS technology and wiring it all up to the rest of the die required a lot of ingenuity on the side of the Intel engineers, as as previously noted this adder is effectively always used in any operation at some stage. This necessitates many surrounding registers and in turn circuitry to manage these, with part of the complexity handled in microcode and part in silicon.

One of the joys you get to experience whether as a proud parent or pet owner is that a lot of things get left around haphazardly. You could of course pick every piece of discarded clothing, half-destroyed toy and detritus yourself, but as a parent of three children himself [Nathaniel Nifong] opted to use his engineering background to potentially over engineer a wires-suspended robotic claw to do this picking up for him.

What he calls Stringman robots requires an anchoring point at four corners of a room, after which the robotic crane can then scour across the ceiling, identify targets to pick up and move these to predesignated drop-off points. It’s an open source project with the LeRobot-based firmware available on GitHub in addition to build instructions for the physical hardware. There’s also a pilot run of ready to use hardware and kits for those who want to trial it, but aren’t interested in building it themselves via [Nathaniel]’s company website.

The basic idea is that this crane can run for an hour or so and deal with the mess in its room without having to do anything yourself. The process isn’t perfect yet, of course, with the underlying diffusion transformer to implement machine vision requiring more refinement. The gripper itself struggles with objects like books, which can be a concern for parents and bookworms, and of course while the crane is operating the wires will dip down as a potential risk to anyone in the room.

Compared to an overhead crane like a traditional bridge crane this wire-suspension crane is probably more stable, but either is an interesting engineering challenge when applied to a household. Next it would probably also be cool if items could be put away where they belong instead of dropped into a bin, as so far that task will still be left to deal with by the adult humans.

Want to make your own ergonomic mouse but don’t know where to start? Why not try [psudoku]’s Kotinos design?

It’s a scaffold-like fingertip shell that uses the internals of an HSK Pro mouse. Each fingertip gets its own little saddle-shaped nook, and things like hand size and paddle surface can all be configured by modifying the OpenSCAD scripts.

[psudoku]’s unit looks to us as though it was maybe made using multi-jet fusion (MJF) 3D printing, but it should be perfectly printable on hobbyist printers, whether resin- or filament-based.

Comfort of the contact surfaces is left up to the end user, but if your print lacks smoothness and sanding isn’t your jam, you might consider a layer of fabric tape to create a velvet-like surface on a 3D print. That’s a trick we’ve kept in mind ever since seeing it put to good use, cushioning the hardware in a DIY steam deck case.

Is the minimalist scaffold approach to a mouse not your style, or does your hand crave something less lightweight but a little more personalized? You might want to craft a truly custom-fitted mouse, for which clay is the way.

You have to be a pretty big aviation nerd to know about [Willard Ray Custer] and his channel wing concept, but if you are, you’ll be giddy to hear about the semicircular profile of the HopFlyt Cyclone drone’s tandem wings. If you’re not quite that much of a nerd, please keep reading, because it’s a really neat concept that never — er — quite got off the ground.

[Custer]’s idea was pretty simple, and born of a shift in reference frame — he realized that only the relative wind over the wing mattered, not the airspeed of the entire aircraft. The same idea drives every blown-wing short-takeoff-and-landing (STOL) project from the DHC-7 turboprop airliner to the An-72 cargo jet: air from the engines washes over the wings, creating lift. Where [Custer] went further is that rather than blowing air over a straight wing, he wrapped the wing under the propeller in a semicircle to maximize the area of lower pressure — and thus lift — creating the “channel wing” that bears his name.

Theoretically, an aircraft with channel wings and powerful enough engines might be able to do vertical takeoffs just from the blown lift, but none of [Custer]’s prototypes demonstrated that — just excellent short-field capability. The HopFlyt drone would be the same, except that, being a tandem, it has double the channel wings of [Custer]’s more-conventional designs, and it’s also a tilt-wing to boot. In that mode, the added low-speed lift from the channel wing makes transitions easier than they otherwise would be — which isn’t anything to sneeze at, since transitioning from vertical to horizontal flight has always been the real bane of VTOL projects.

They’re claiming a reduced fuel burn of 10% in hover and transition thanks to the extra lift from the channel wings. You can see their prototype in action in the demo video embedded below. We once featured a project that went even further, blowing air across a special hollow wing for propulsion and blown lift. The easiest eVTOL project still starts with a quadcopter, though.

Microsoft has a history of taking accessibility options seriously for gaming controllers, and that trend continues with downloadable thumbstick toppers for Xbox controllers. Being straight from the source, the 3D models should fit as well as can be expected with a minimum of fiddling. Just make sure you select the right controller model, because they are each subtly different.

The toppers themselves come in different styles, and there’s a design to fit a variety of needs, from a thumb cradle to ones intended for more serious adaptations —  the perforated X-shaped topper, for instance, is meant to anchor a custom shape molded overtop it.

Microsoft does offer a remarkably hackable adaptive controller that is meant to make it easy to integrate with other hardware, and we’ve seen it used in some truly awesome ways. But it’s nice to see an easy way to extend and adapt normal thumbsticks on regular controllers, giving people even more options.

We love to see companies offer useful 3D models of their products, saving consumers from having to 3D scan or model things themselves. It’s a form of hacker-friendly hardware design, which we celebrate when we see it, while at the same time wishing it were more common.

Have you benefited from hacker-friendly design and made something useful that wouldn’t exist otherwise? Let us know on the tips line!

Fluoroscopy is probably the best-known method of X-ray imaging: an X-ray beam passes through the subject to be imaged, and the transmitted X-rays illuminate a phosphor screen. Dense objects, such as metal or bone, cast a shadow on the screen, which provides a real-time image of the subject’s interior. Already having access to X-ray sources, [MarcellF]’s next step was to investigate common phosphor materials, then synthesize his own.

Most common materials that fluoresce under ultraviolet light showed no activity under X-rays: fluorescein, quinine, UV fluorescent paint, and common fluorescent minerals emitted no noticeable glow under 80 kV X-ray stimulation. However, strontium aluminate phosphors did fluoresce well, with a strong afterglow, as did the phosphors in a fluorescent light bulb, some LEDs, and an electroluminescent panel. The electroluminescent panel, which used a zinc sulfide phosphor, was almost as bright as the gadolinium oxysulfide screen from a CT scanner’s detector and had no noticeable afterglow.

One well-known X-ray phosphor is scheelite (calcium tungstate), which [MarcellF] next synthesized. He had previously tested a sample of natural scheelite without success, probably due to impurities. The first step of the synthesis was to melt together potassium nitrate and sodium carbonate, in which [MarcellF] dissolved broken pieces of a tungsten TIG welding rod. This formed sodium and potassium tungstates, which were dissolved and reacted with a calcium chloride solution. This precipitated calcium tungstate, which [MarcellF] annealed to make fluorescent. This produced a blue glow under X-ray stimulation, and doping with lead atoms made it significantly brighter.

We’ve covered several methods of X-ray detection before; most modern fluoroscopes now use a phosphor screen in conjunction with a camera, or sometimes with a photomultiplier tube.

Times are tough out there, and many are starting to feel the pressure at the grocery store checkout line or the gas pump. But whenever you start to worry about affording life’s necessities, take comfort in the knowledge that somebody is so flush with cash that on Friday they decided to treat themselves and spend $3 million for a sealed copy of Super Mario Bros for the Nintendo Entertainment System.

Although we’re not going to say it necessarily justifies the insane price — a new record for the most ever paid for a video game, incidentally — Heritage Auctions does note in their press release that this is an exceptionally rare version of what’s admittedly one of the most iconic pieces of software ever produced. This is only one of three copies of this particular variant known to exist, which Nintendo apparently distributed to test markets in the United States ahead of the game’s official 1985 release.

In slightly more modern gaming news, Asha Sharma, the new head of Microsoft’s Xbox division, has been making some big swings to try and get Microsoft’s gaming division back on track after years of declining sales. As part of that effort, she recently penned an article detailing some of the challenges the company is facing, which includes some interesting hardware details.

According to the blog post, she claims that in February, the cost of memory and storage components for the Xbox console had doubled compared to the previous year. But those numbers have jumped again, and by the time the holidays roll around, she expects they’ll be paying five times what they did in 2024. That’s bad news for anyone looking to put an Xbox under the tree come Christmas, but even worse news as the company works on the console’s successor. Considering that today’s hardware from Sony and Microsoft can already set you back $700 USD depending on which version you get, it seems like we’re approaching a point where gaming consoles could price themselves out of the market.

Those thinking of mowing some lawns this summer to save up for their $1K next-generation consoles may be interested to hear that the Food and Drug Administration has put its stamp of approval on the first new sunscreen ingredient in the US in more than two decades. Bemotrizinol is a broad-spectrum UV absorber that knocks out 310 and 340 nm, and while Uncle Sam has taken his sweet time to give it the OK, the European Union has been slathering it on since 2000. The first company authorized to sell it in the US will be marketing it under the name Parsol Shield later this year, with other manufacturers set to follow in 2027.

While it seems the world has agreed on adding bemotrizinol to their sunscreens, many people are decidedly less enthusiastic about AI code in their open-source projects. One of those people is Drew DeVault, which is why he decided to fork Vim once he found out its maintainers were merging in code written by large language models (LLMs). Rather than break off at the last version untainted by clankers, Drew decided to divert from the upstream project at version 8.2.x. This means that some newer plugins may have compatibility issues, although security fixes and other selected updates from the 9.x branch have been back-ported to the newly coined Vim Classic. If you give it a shot, let us know in the comments.

Finally, if a non-AI fork of Vim is still too mainstream to scratch that itch for you, Phoronix is reporting that ReactOS can now run Half Life. If this were any other website, we might devote the next paragraph to explaining the significance of a nearly 30-year-old PC game being run on a free and open-source operating system designed to provide binary compatibility with Microsoft Windows. But it’s Sunday evening, and you’re reading Hackaday, so just take the win.

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