Although not the first to try and build a DIY solar-powered remote control airplane, [ProjectAir]’s recent attempt is the most significant one in recent memory. It follows [rctestflight]’s multi-year saga with its v4 revision in 2019, as well as 2022’s rather big one by [Bearospace]. With so many examples to look at, building a solar-powered RC airplane in 2024 should be a snap, surely?
The first handicap was that [ProjectAir] is based in the UK, which means dealing with the famously sunny weather in those regions. The next issue was that the expensive, 20% efficient solar panels are exceedingly fragile, so the hope was that hot-gluing them to the foam of the airplane would keep them safe, even in the case of a crash. During the first test flights they quickly found that although the airplane few fairly well, the moment the sun vanished behind another cloud, the airplane would quite literally fall out of the sky, damaging some cells in the process.
There’s something magical about volumetric displays. They really need to be perceived in person, and no amount of static or video photography will ever do them justice. [AncientJames] has built a few, and we’re reporting on his progress, mostly because he got it to run a playable port of DOOM.
Base view of an earlier version showing the motor drive and PSU
As we’ve seen before, DOOM is very much a 3D game viewed on a 2D display using all manner of clever tricks and optimizations. The background visual gives a 3D effect, but the game’s sprites are definitely very solidly in 2D land. As we’ll see, that wasn’t good enough for [James].
The basic concept relies on a pair of 128 x 64 LED display matrix modules sitting atop a rotating platform. The 3D printed platform holds the displays vertically, with the LEDs lined up with the diameter, meaning the electronics hang off the back, creating some imbalance.
Lead, in the form of the type used for traditional window leading, was used as a counterbalance. A Raspberry Pi 4 with a modified version of this LED driver HAT is rotating with the displays. The Pi and both displays are fed power from individual Mini560 buck modules, taking their input from a 12 V 100 W Mean-Well power supply via a car alternator slip ring setup. (Part numbers ABH6004S and ASL9009 for those interested.) Finally, to synchronise the setup, a simple IR photo interrupter signals the Pi via an interrupt.
Many have sought the holy grail of making commercial media both readable and copy-proof, especially once everyone began to copy those floppies. One of these attempts to make floppies copy-proof was Softguard’s Superlok. This in-depth look at this copy protection system by [GloriousCow] comes on the heels of a part one that covers Formaster’s Copy-Lock. Interestingly, Sierra switched from Copy-Lock to Superlok for their DOS version of games like King’s Quest, following the industry’s quest in search of this holy grail.
The way that Superlok works is that it loads a (hidden) executable called CPC.COM which proceeds to read the 128 byte key that is stored on a special track 6. With this key the game’s executable is decoded and fun can commence. Without a valid ‘Play’ disk containing the special track and CPC.COM executable all one is instead left with is a request by the game to ‘insert your ORIGINAL disk 1’.
Sierra’s King Quest v1.0 for DOS.
As one can see in the Norton Commander screenshot of a Sierra game disk, the hidden file is easily uncovered in any application that supports showing hidden files. However, CPC.COM couldn’t be executed directly; it needs to be executed from a memory buffer and passed the correct stack parameters. Sierra likely put in very little effort when implementing Softguard’s solution in their products, as Superlok supports changing the encryption key offset and other ways to make life hard for crackers.
Sierra was using version 2.3 of Superlok, but Softguard would also make a version 3.0. This is quite similar to 2.x, but has a gotcha in that it reads across the track index for the outer sector. This requires track wrapping to be implemented. Far from this kind of copy protection cracking being a recent thing, there was a thriving market for products that would circumvent these protections, all the way up to Central Point’s Copy II PC Option Board that would man-in-the-middle between the floppy disk drive and the CPU, intercepting data and render those copy protections pointless.
As for the fate of Softguard, by the end of the 1980s many of its customers were tiring of the cat-and-mouse game between crackers and Softguard, along with issues reported by legitimate users. Customers like Infographics Inc. dropped the Superlok protection by 1987 and by 1992 Softguard was out of business.
All of the usual tiny superlatives and comparisons apply to [Chronova Engineering]’s latest effort — fits on a pencil eraser, don’t sneeze while you’re working on it or you’ll never find it. If we were to put the footprint of this engine into SMD context, we’d say it’s around a 2010 or so. As one would expect, the design is minimalistic, with no room for traditional bearings or valves. The piston and connecting rod are one piece, meaning the cylinder must pivot, which provides a clever way of switching between intake and exhaust. Tiny crankshaft, tiny flywheel. Everything you’d associate with a steam engine is there, but just barely.
The tooling needed to accomplish this feat is pretty impressive too. [Chronova] are no strangers to precision work, but this is a step beyond. Almost everything was done on a watchmaker’s lathe with a milling attachment and a microscope assist. For the main body of the engine, a pantograph engraving machine was enlisted to scale a 3D printed template down tenfold. Drill bits in the 0.3 mm range didn’t fare too well against annealed tool steel, which is where the scanning electron microscope came into play. It revealed brittle fractures in the carbide tool, which prompted a dive down the rabbit hole of micro-machining and a switch to high-speed steel tooling.
It all worked in the end, enough so that the engine managed 42,000 RPM on a test with compressed air. We eagerly await the equally tiny boiler for a live steam test.
In a recent photo essay for the New Yorker magazine, author Keith Gessen and photographer Andrew McConnell share what life is like for the residents around the launch facility and where Soyuz capsules land in Kazakhstan.
Read the article for a brief history of the Baikonur spaceport and observations from the photographer’s fifteen visits to observe Soyuz landings and the extreme separation between the local farmers and the facilities built up around Baikonur. A local ecologist even compares the family farmers toiling around the busy spaceport to a scene our readers may be familiar with on Tatooine.
Media formats have come a long way since the early days of computing. Once upon a time, the very idea of even playing live audio was considered a lofty goal, with home computers instead making do with simple synthesizer chips instead. Eventually, though, real audio became possible, and in turn, video as well.
But what of the formats in which we store this media? Today, there are so many—from MP3s to MP4s, old-school AVIs to modern *.h264s. Senior software engineer Ben Combee came down to the 2023 Hackaday Supercon to give us all a run down of modern audio and video formats, and how they’re best employed these days.
[Breaking Taps] has a look at “parkerization” — a process to coat steel to prevent rust. While you commonly see this finish in firearms, it is usable anywhere you need some protection for steel parts. The process is relatively easy. It does require heat and a special manganese solution made for the purpose. You scuff up the surface of the steel and degrease and wash it.
Once the part is ready, you insert the part in hot solution which is manganese and phosphoric acid. Rinse and displace the water and you are ready to oil the part.
But what we really liked was the electron micrographs of the steel before and after the process. The phosphates formed in the solution cover the iron and hold oil to prevent oxidization. However, the first attempt wasn’t uniform so it wouldn’t work as well. [Breaking Taps] thinks it was a failure to rough up the piece sufficiently before starting. He also raised the temperature of the bath and got a better, but not perfect, result.
We miss having an electron microscope at work and we really want one at home! The last fun coating project we remember used copper in a strange and wonderful way.
