TechyMagThings

In this age of neural net “AI”, even the most skeptical of Butlerians have to agree that these machine learning models can be very, very good at pattern recognition if nothing else. NASA is on the same page, and to take advantage of that pattern recognition, they’ve built a machine learning module called COFFIES, which stands for Consequence Of Fields and Flows in the Interior and Exterior of the Sun, because at NASA everything is an acronym, or at least a backronym. Like most such names, this one is at least vaguely descriptive: the model is trying to predict what’s going on in the material flows and magnetic fields deep within our local star, and using those inferences is able to predict active regions– that’s sunspots to us chickens — up to 12 hours before they visibly form.

The measurements used here are indirect —  we can’t chart the magnetohydrodynamic snarls deep inside a star directly, but we can measure the magnetic field and acoustic waves at and above the surface. You could say the model “hears” sunspots forming. Like all such models, it’s a bit of a black box, but heliophysicists may be able to use its predictions to help them understand their own, organic understanding of the big ball of plasma to which we all owe our lives.

This model is thus one of the better things to come out of the “AI” revolution– nobody is going to give over their thinking to the machine and stop trying to understand the Sun, and the few hours of extra warning COFFIES might potentially provide before the next Carrington Event-class geomagnetic storm could prove invaluable, especially since a flare-blocking Storm wall remains a theoretical exercise at best. If you are interested in the sun, COFFIES has an interesting YouTube channel and, as you can see in a recent video, they are doing a lot with AI.

Sometimes claimed to give you wings, energy drinks can, at the very least, be used to make rockets fly. This is what [Nate Scovill] did in a recent video, where cans of the sugary stuff are processed to give a rocket its proverbial wings.

The basic concept is so-called rocket candy, which uses the fact that sugar is a pretty decent fuel type that — when combined with an oxidizer like potassium nitrate — can be turned into solid rocket fuel. Naturally it’d be easiest to start off with a pure source of sucrose or sorbitol for the sugar, but what if you only have access to cans of sugary soda?

Removing the moisture from the energy drink was the obvious first step, as water and rocket fuel aren’t a great mix. Adding and mixing potassium nitrate to the resulting thick syrup created the fuel-oxidizer mixture, also known as rocket fuel. This did take a detour involving removing the carbonation using a vacuum chamber, as CO₂ and fire do not really like each other either.

We previously covered making your own rocket candy, though it’s far from the only rocket fuel that can be made at home using products bought at the local supermarket. Obviously, doing so comes with a whole heap of risks, not least of which is the notion that the difference between a rocket and a bomb is a pretty thin and fuzzy line that you do not want to accidentally cross.

Steam power is a staple of the steampunk aesthetic, thermodynamics, and a checkpoint for the budding mechanical engineer studying heat cycles. But because food is largely made of water, steam is also common in the culinary arts. So it’s no surprise that when thermodynamics is applied to cooking, exciting things can happen. 

This particular example of steam-powered culinary happenings is inspired by industrial potato-peeling machines. By adding high-pressure, high-temperature steam to a pressure vessel with potatoes inside, heat can transfer more easily to the inside of the potatoes. Because the pressure is so high, however, the water in the skin won’t boil. This is fundamentally the same concept as a pressure cooker. However, what’s different is that instead of a pressure cooker’s slow release, these industrial peeling machines rely on explosive decompression, flash boiling the water underneath the potato’s skin. This rapidly expanding steam rips away the skin in a nice clean sheet.

But, to [Stuff Made Here’s] disappointment, there were no videos of the process on the internet. But, fortunately for us, being an engineer of complicated machines means that there is one now that you can watch below.

The machine itself is, on paper at least, fairly simple. It consists of a boiler, connected to a fruit chamber by a valve, and another valve to vent the steam out of the fruit chamber. However, engineering a pressure vessel that can safely withstand over 1,000 kPa of steam with a window for filming when you can’t weld very well is another matter entirely. The boiler is two stainless steel plates with a cylinder in the middle, with face seals used to keep the chamber steam-tight. A custom jig was needed to machine the pipe ends flat enough to mate with the seals. It’s held together with threaded rods. However, because the rods and the vessel body have different thermal expansion coefficients, Belleville washers are used as expansion joints in the system.

The fruit chamber is welded together because it experiences lower pressures. This also allows for a less sensitive O-ring seal on the door, reducing the work required to use the door. A glass piece inlaid into the steel door provides a view, held in place by pressure and 3D-printed brackets. A stand holds the fruit centered within the window for our viewing pleasure!

The results speak for themselves, though operation is complicated and dangerous, and it can only peel one fruit at a time; the skin of nearly every example placed inside is perfectly removed. Experiments include apples, potatoes, grapes, lemons, strawberries, blackberries, and (pictured above) popcorn on the cob. It’s quite a fun demonstration of the thermodynamic principles at play!

Thanks [DjBiohazard] for the tip!

It’s a sci-fi trope that you can ‘scan for life signs’ and detect if there are humans — or suspiciously human-shaped aliens — present, but in real life it’s harder than that. [The Masked Bear]’s wifisense-pi project isn’t really scanning for signs of life, either, unless you happen to consider breathing a sign of life. Even then, it’s not detecting breathing per se, but the subtle motion that goes with it: it’s a very sensitive motion detector that relies on the fact that we fleshy bags of goo disturb WiFi signals with our presence, and motion alters those disturbances.

The device uses an ESP32-S3 to measure the radio channel 100 times per second, while a Raspberry Pi 4 provides the signal processing muscle. It can detect the slightest motions, and even determine the presence of a perfectly still human by their breathing, though you can hide your presence for as long as you can hold your breath. A single sensor, no matter how sensitive, cannot give position information, and while multiple humans will distort WiFi more than a single one, [The Masked Bear] reports you cannot reliably extract that signal. So this project answers the question: “are there humans in this room?” Or, even more likely, “are there any large breathing animals in this room?” We can’t imagine a 50 kg Mastiff looking any different to this sensor than an equivalent mass of quivering human flesh.

Before you dismiss this as just another motion sensor, keep in mind that it is sniffing the signals already present on the 2.4 GHz band, and, like the WiFi signals themselves, it can work through walls. So we think it’s pretty nifty. Of course, there are many other ways to detect humans, from machine-learning cameras to millimeter-wave sensors to a simple PIR. This isn’t the first project we’ve seen that uses WiFi like this. It isn’t even the first with an ESP32, but it’s an interesting implementation worth checking out.

Remember Animusic? They were these incredible animated music videos with original tunes being played by computer-generated robots. Well, the MegCell Pulse might be the coolest robots-playing-music thing we’ve seen since Animusic.

Built by [Bruce] over six years’ time, this futuristic wonder features two robots working in concert to play acoustic guitar, just like a pair of human hands would. You just feed them digital tablature, and off go the fraternal twins, with one doing the fretting, and the other doing the plucking via six individual plectrum. It’s digital music producing analog sound from a physical instrument.

How does MegCell Pulse work? It’s essentially a system of gears, magnetic actuators, and arms, contained in a 3D-printed structure. The only real limitations are that it can’t traverse the entire fretboard, nor can it slide between frets. That said, you can absolutely buy one for your own guitar via [Bruce]’s modestly-goaled Kickstarter.

The kicker here is that you can’t buy an assembled MegCell Pulse; you must print and build it yourself. Back on the upside, the most expensive supporting tier is a mere $100. For that price, you get the complete digital plans. That includes 3D print files, an assembly guide, the control software, and a parts list. Be sure to check out the demo videos embedded after the break.

We have certainly seen robots playing guitars before, although admittedly, it’s been a minute.

After the Nintendo 3DS handheld console saw most its online services including the online store (eShop) taken offline not too long ago, it was only a matter of time before the demise of even the remaining paid services, such as the Pokémon Bank which Nintendo has now announced will be shutting down on February 25 of 2027.

The ability to transfer the digital pocket monsters, or Pokémon, between physical systems has been a staple of the series since the early Gameboy days when a link cable would be all you needed to trade and catch’em’all, as they say in the trade. Naturally over time this Cloud-based aspect wormed its way into this series as well, starting with the 3DS and this continuing on the Nintendo Switch in the form of the Pokémon HOME app.

With this paid service an avid Pokémon fan could collect up to 3,000 of these digital critters, move them between various Pokémon games and generally allow players to keep the same Pokémon with them across games. As noted by [Kevdog Plays] in an informative video on what to do before the shutdown, the service is free during these final months.

What’s interesting is that certain Pokémon can only be obtained from 3DS Pokémon games, which means that without either an alternative to this transfer mechanism or these games becoming available on newer Nintendo consoles, there will forever be that gaping hole in one’s Pokedex. Naturally this raises the usual questions about software archiving and preservation when an online service is required for the full game experience.

Doing anything on a frozen lake can carries some amount of risk. Nevertheless, every year events ranging from car racing to ice skating are held on them. As such, proper safety precautions are needed, the most important of which is ensuring the ice is thick enough to withstand the weight of whatever may be on it. This is done by cutting holes into the ice and measuring its depth in several locations. But this is a dangerous and imperfect process only giving a rough picture of actual thickness. So to solves these problems, a team of students at ETH Zurich made an ice measuring submersible drone. 

The concept of ice measurement employed is, on paper, reasonably simple. When a sonar pulse is sent out, some of the energy will return off the bottom of the ice sheet, but some of it will pass through creating a second return. By measuring the difference in these two returns, the thickness can be calculate with a high degree of precision. Attach the sonar to a submersible and give it a positioning system and you can simply get a thickness map, right? Well, employing theory in practice is a far more complicated prospect as the students soon found out.

The submersible itself is slightly positively botany. It features two concrete ballasts to adjust the center of cavity and six propulsion motors for six degrees of freedom. It’s powered by a NVIDIA Jetson to allow for autonomous operations and a whole host of sensors. Navigation is handled by a variety of sensors, mostly GPS and SBL. The GPS antenna sits in a radome at the top of the submersible, allowing for a strong enough signal for a positional fix when touching the bottom of the ice. SBL works similarly to sonar, where a transmitter on the submarine sends out an audio ping, received by a trio of hydrophones used to calculate the drone’s position.

But does all this complexity really work? Well, mostly. A number of real-world factors greatly compound the submarine’s effectiveness. The signal noise from in the sonar makes accurate measurements nigh impossible with that methodology. As such, the team used a depth based approach, by touching the submarine to the bottom of the ice, and measuring the water pressure and therefore depth, the ice’s thickness can be easily calculated. However, this method too is not without flaws. When snow falls on alpine lakes, it pushes the ice sheet downward, and a new ice sheet can form on top. This top sheet’s layer is what’s most important, but the depth measurement can only take into account the overall sheet’s thickness. Regardless, this was a really impressive first test of the submersible, and we look forward to seeing where it goes from here!

Make sure to check out this autonomous submarine next!