For most of us, ice isn’t something we’ve thought about in detail since our high school science classes. For most of us, we pour some tap water into the ice trays, slam it in the freezer, and forget about it. Then we lob the frozen misshapen cubes into a beer and enjoy a quite literally ice-cold beverage.
However, there’s so much more fun to be had with ice if you really get into it. If you’ve ever wondered how pretentious cocktail bars make their fancy ice spheres or transparent cubes, read on!
Why bananas, you ask? Because [Marius Heier] uses them to demonstrate what we all intuitively know — that rubbing something over and over again tends to wear it away — but engineers seem to have forgotten. Wear such as this, with resistance material rather than fruits, is what causes the dreaded drift, a problem that the world collectively spends $20 billion a year dealing with, according to [Marius].
While numbers like that seem to be firmly in class-action lawsuit territory, sometimes it’s best to take matters into your own hands and not wait for the courts. The fix [Marius] shows here is to yank the potentiometers off a PS4 joystick and replace them with contactless Hall effect sensors. The end of the shaft for each axis gets a diametral neodymium magnet attached to it, while a 3D printed bracket holds a tiny custom PCB in close proximity. The PCB has an AS5600 Hall sensor, which translates the shaft angle to an analog voltage output. After programming the chip over its I2C bus, the sensor outputs a voltage proportional to the angle of each shaft, just like the original pots, but without all the wear and tear.
While [Marius] is selling these as drop-in replacements for PS4 controllers, he plans to release all the design files so you can build one yourself. He also has his sights set on replacements for PS5 and Xbox controllers, so watch for those. This isn’t his first foray into joystick hacking, having shared his 3D Hall effect and haptic feedback joysticks with us previously.
In science fiction movies, communicating with aliens is easy. In real life, though, we think it will be tough. Today, you’ll get your chance to see how tough when a SETI project uses the European Space Agency’s ExoMars Trace Gas Orbiter to send a simulated alien message to the Earth. The transmission is scheduled to happen at 1900 UTC and, of course, the signal will take about 16 minutes to arrive here on planet Earth. You can see a video about the project, A Sign in Space, below.
You don’t need to receive the message yourself. That will be the job of observatories at the SETI Institute, the Green Bank Observatory, and the Italian National Institute for Astrophysics. They’ll make the signal available to everyone, and you can join others on Discord or work solo and submit your interpretation of the message.
Drake’s message properly arranged
There are a host of issues involved in alien communication. What communication medium will they use? How will they encode their message? Will the message even make sense? Imagine an engineer from 1910 trying to find, decode, and understand an ad on FM radio station 107.9. First, they’d have to find the signal. Then figure out FM modulation. Then they’d probably wonder what the phrase “smartphone” could possibly mean.
When [Frank Drake] created a test message to send to aliens via the Arecibo dish, almost no one could decode it unless they already knew how it worked. But even looking at the message in the accompanying image, you probably can only puzzle out some of it. Don’t forget; this message was created by another human.
If you want a foreshadowing of how hard this is, you can try decoding the bitstream yourself. Of course, that page assumes you already figured out that the stream of bits is, in fact, a stream of bits and that it should be set in an image pattern. You also have the advantage of knowing what the right answer looks like. It could easily become an extraterrestrial Rorschach test where you find patterns and meaning in every permutation of bits.
Speaking of the Drake message, it saddens us to think that Arecibo is gone. The closest we think we’ve come to intercepting alien messages is the Wow signal.
While the Commodore 64 was an immensely popular computer for its time, and still remains a strong favorite within the retrocomputing community, there’s a reason we’re not using modern Commodore-branded computers today. Intense competition, company mismanagement, and advancing beyond 8-bit computers too late in the game all led to the company’s eventual downfall. But if you’re still a Commodore enthusiast and always wished you were able to get an upgraded C64, you might want to take a look at the Commander X16, a modern take on this classic computer.
We’ve actually seen the Commander X16 before, but this was back in its early days of prototyping and design. This video from [Adrian’s Digital Basement], also linked below the break, takes a look at how it’s come in the four years since [David Murray] started this project. At its core, it’s an 8-bit 6502-based computer like you’d find in the 1980s but built with new components. There are some more modern updates as well such as the ability to use an SD card as well as built-in SNES controller ports, but the real magic here is the VERA module. Built around an FPGA, this module handles graphics, some of the audio, and the storage capabilities and does all of these things much better than the original Commodore, while still being faithful to what made these computer great.
While the inclusion of the FPGA might offend some of the most staunch 8-bit purists, it turns out to be necessary due to the lack of off-the-shelf video chips and really makes this build shine in the end. It’s also capable of running 6502-based software from other machines too, including the original NES. The VERA module makes it possible to run other software too, including a sample of Sonic the Hedgehog from the Sega Genesis which [Adrian] demonstrates in his video. 6502-based computers are quite versatile as the Commander X16 demonstrates, and it’s even possible to build a rudimentary 6502 on a breadboard with just a few parts.
Since sound is the primary sense used by most ocean life, disruptions to the natural noise levels in the ocean from human activities can be particularly problematic for marine life. [DW Planet A] has a video describing some of the ways we can mitigate these disruptions to our friends under the sea.
Being noisy neighbors isn’t just a problem for whales but for everything down to the plankton at the base of the food web. Underwater construction like offshore wind installations get flak for being noisy, but technologies like bubble curtains can reduce noise output by up to 90% to the surrounding waters while still getting those nice low carbon energy benefits that prevent further ocean acidification and warming. Continue reading “Keeping The Noise Down Under The Sea”→
Gyroscopes are one of those physics phenomena that are a means to many ends, but can also enjoyed as a fascinating object in their own right. Case and point being [Hyperspace Pirate]’s tightrope-balancing crawler in the video after the break.
Inside the PLA and aluminum shell is a 3D-printed wheel with steel bolts around the edge for added moment of inertia. It is powered by a low-KV brushless motor with a 3:1 GT2 belt-drive and controlled by a simple servo tester, running on a 4 cell LiPo battery. The 3D-printed drive wheel is powered by a geared DC motor hooked directly to the battery. [Hyperspace Pirate] goes over the math of the design, showing that path to stability is a high speed and high moment of inertia flywheel, while staying well within the strength limits of the wheel’s material.
It’s balancing act was first demonstrated on a length of PVC conduit and then on a section of rope, with the characteristic circular wobbling of a gyroscope, known as gyroscopic precession. Without active correction, this the angle of procession will steadily increase until the machine falls over. Even so, it’s still great to watch a small scale version, like the one that inspired this build, would make a pretty cool desk toy.
Gyroscopes are commonly used in attitude indicators and and heading indicators in aircraft, and we’ve also seen them get used for balancing robots. Any ideas for practical uses for a mono-wheel rail/rope walker? Drop them in the comments below.
For those of us who don’t do it every day, handling sheet metal can be a nerve-wracking affair. Sheet metal is thin, heavy, and sharp, and one wrong move while handling it can have much the same result as other such objects, like guillotine blades. If only there was a way to lessen the danger.
Perhaps something like this electromagnetic sheet metal handler by [Lucas] over at “Cranktown City” would be useful in keeping one’s fingers and toes attached. Like many interesting builds, this one starts with the dismemberment of a couple of old microwave ovens, to liberate their transformers. Further dissection resulted in open-frame electromagnets, which when energized with a battery from a Ryobi cordless tool do a fine job sticking to stuff.
[Lucas] then harvested the battery connector from the cheapest possible Ryobi tool — an electric fan — and built a prototype, which worked well enough to proceed to a more polished version two. This one had the same guts in a nicely designed case, 3D-printed from lime green filament for that OEM look. The video below shows the design and build, as well as field testing. We have to say this gave us a bit of pause, especially when the battery popped out of one of the handlers and sent the sheet on a near-miss of [Lucas]’ toes. Close call there.
