Last year, mathematician and professional optical illusionist [Kokichi Sugihara] came up with an arrow that only points one way. Technically, it’s ‘anomalous mirror symmetry’, but if you print this arrow and look at it juuuussst right, it appears this arrow only points one way.
[Ali] had the idea to turn this arrow illusion into something motorized, and for that he turned to 3D printing. The models for the illusion arrows were already available, but there had to be a way to turn a single arrow into an art installation. For that, you just need a few 9g servos. [Ali] slightly modified his servos so they would turn a full 180 degrees, and designed a magnetic mount to allow easy swap-out of these arrows.
The servos are attached to a 3D printed frame with heat-staked threaded inserts, and driven by a Pololu servo driver. The effect is great, with multiple arrows twisting and turning but still only appearing to point to the right. [Ali] put together two videos of this arrow illusion, one that’s effectively a build guide, and of course all the STLs are available in a link in the description.
We might not think of analog computers as having existed in the 1500s, but in fact the astrolabe first appeared around 220 BC. However, as you might expect only a few very old ones still exist. Early astrolabes were often wooden and were difficult to use aboard ships, however brass astrolabes with special features were more accurate on the deck of a ship underway. A recent archeological find from one of Vasco da Gama’s ships that sunk in the Arabian Sea has brought the number of known archeologically-significant instruments to 104, and also is one of the few nautical versions to employ a solid disk. As of now, it is the oldest known maritime astrolabe found so far — the ship sunk in 1503. You might wonder how the 104th astrolabe became number 108, but the catalog includes a few pieces or fragments of astrolabes. If you count those, there are 108 items in the catalog.
If you think archeology is about men in fedoras carrying whips, or stuffy old men wandering around tombs, you should have a look at the article about this find. In addition to divers recovering the piece from the shipwreck (see the video, below), the science involved in restoring it and analyzing it includes chemistry, lasers, X-rays, and energy-dispersive spectroscopy.
If you’re reading this article on a desktop or laptop computer, you’re probably staring at millions of pixels on a TFT LCD display. TFT became a dominant technology due to its picture quality and fast response times, but it’s not the only way to build an LCD. There are cheaper technologies, such as STN and its color variant, CSTN. They’re rarely used nowadays, but [Wenting Zhang] had one lying around and wanted to take a crack at driving it.
The screen in question came courtesy of a 20th century laptop. It’s a Hitachi SX21V001-Z4, with a resolution of 640×480 pixels. Driver boards for CSTN screens were once readily available, however now such things are difficult to come by.
[Wenting] instead grabbed an FPGA and got to work. Driving displays can be taxing for small microcontrollers, so an FPGA is always a great choice when working on such projects. They’re easily capable of generating whatever weird and wacky signals are required, and can generate many such signals in parallel without breaking a sweat.
[Wenting] successfully got the screen up and running, and hooked up to a VGA input. Image quality is surprisingly passable for still images, though things absolutely go to pieces when motion is introduced. [Wenting]’s demo shows off the screen playing Breath of the Wild, and it’s a great showcase of how far technology has come since the mid-90s.
Driving strange LCDs is a hacker rite of passage, and we see plenty of efforts around these parts. Video after the break.
Hackers absolutely love building clocks. Seriously, there are few other devices for which we’ve seen such an incredible number of variations. But while the clocks that hackers build might blink out the time in binary, or write it out in words, they generally don’t feature hands. Apparently in 2019 it’s more reasonable to read binary than know which way the “little hand” is supposed to be pointing.
This ESP8266 powered “shadow clock” from [Dheera Venkatraman] technically keeps that tradition intact, but only just. His clock doesn’t feature physical hands, but it does use a strip of RGB LEDs to cast multi-colored shadows which serve the same function. With his clock, you don’t even have to try and figure out which hand is the big one, since they’re all the same length. Now that’s what we call progress.
Probably the biggest surprise about this clock, beyond how legitimately good it looks hanging on the wall, is how little work it takes to build your own version. That’s because [Dheera] specifically set out to design something that was cheaper and easier to build than what he’d seen previously, and we think he delivered on that goal in a big way. All you need are the 3D printed components, an ESP8266 board, and a strip of 144 WS2812B LEDs.
The software side of the project is similarly simplistic, and all you need to do is plug in your WiFi network credentials to have the ESP pull the current time from NTP. If you were so inclined, his source code would be an excellent base on which to implement additional features such as animations at the top of the hour.
It turns out that Shanghai is a very long way from my home in Wisconsin. I’ve traveled here for Electronica China, and although it made for an incredibly long travel “day”, it turned out to be quite enjoyable. I hacked some hardware on the plane ride, I took a maglev to my hotel, met up with Sophi for drinks, and explored the neighborhood for some Shanghai breakfast. Continue reading “Hacker Abroad: A Very Long Way To China”→
The last few years have seen a rise of artistic PCBs. Whether these are one-off projects with a little graphic on the silkscreen or the art of manufacturing and supply chains, these fancy PCBs are here to stay. Nowhere is this more apparent than the loose confederation of Badgelife enthusiasts, a hardware collective dedicated to making expressive and impressive electronic baubles for various hacker conferences. Here, hundreds of different hardware badges are created every year. It’s electronic art, supported by a community.
Some of these badges aren’t technically badges, but rather small, blinky add-ons meant to connect to a main badge, and these add-ons are all backed by a community-derived standard. The Shitty Add-On Standard is how you put smaller PCBs onto bigger PCBs. It is supported by tens of thousands of badges, and all of the people who are spending their free time designing electronic conference badges are using this standard.
It’s been more than a year since the Shitty Add-On standard was created, and in that time the people behind the work have seen the shortcomings of the first edition of the standard. Mechanically, it’s not really that strong, and it would be neat if there were a few more pins to drive RGB LEDs. This has led to the creation of the latest revision of the Shitty Add-On Standard, V.1.69bis. Now, for the first time, this standard is ready for the world to see.
There was a time when owning a home computer was kind of a big deal. In the days before the popularization of the Internet, so-called “computer shows” were the best way to meet with others to swap advice, information, and hardware. Of course today, things are very different. The kind of people who are building their computers just buy the parts online, and everyone else is probably using a $200 laptop from Walmart that isn’t worth spending the time or money on to upgrade.
So while the Trenton Computer Festival (TCF) may have started in 1976 as a way for people to buy early computers like the Altair 8800, over the years it has morphed into something much closer to the modern idea of a “con”. Those who visit the 44th TCF on March 23rd at the College of New Jersey will likely spend most of their time at the festival attending the 40+ talks and workshops that will be happening in a span of just six hours. But anyone who’s got some cash to burn can still head over to the flea market area where they’ll be able to buy both modern and vintage hardware.
Talks run the gamut from Arduino to quantum computing, and if you don’t see something that piques your interest in this year’s program, one might wonder how you found yourself reading Hackaday in the first place. If you manage to find some spare time between all the talks, the New Jersey chapter of the The Open Organisation Of Lockpickers (TOOOL) will be there giving a hands-on lock picking class, and if you don’t mind taking the crash course, you can even get your ham radio license. All for the princely sum of just $20 at the door.
In fact, there’s so much going on at TCF that it can be somewhat overwhelming. As I found out during my visit last year, the number of simultaneous events means you’ll almost certainly have some difficult decisions to make. I’ll be making the trip out to the College of New Jersey campus again this year for TCF, and will have plenty of Hackaday stickers and buttons to give out to anyone who manages to stop me while I dash between talks.