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.
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.