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Hackaday Links: June 6, 2021

June 6, 2021 by 12 Comments

There are a bunch of newly minted millionaires this week, after it was announced that Stack OverFlow would be acquired for $1.8 billion by European tech investment firm Prosus. While not exactly a household name, Prosus is a big player in the Chinese tech scene, where it has about a 30% stake in Chinese internet company Tencent. They trimmed their holdings in the company a bit recently, raising $15 billion in cash, which we assume will be used to fund the SO purchase. As with all such changes, there’s considerable angst out in the community about how this could impact everyone’s favorite coding help site. The SO leadership are all adamant that nothing will change, but only time will tell.

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Hackaday Links: May 30, 2021

May 30, 2021 by 19 Comments

That collective “Phew!” you heard this week was probably everyone on the Mars Ingenuity helicopter team letting out a sigh of relief while watching telemetry from the sixth and somewhat shaky flight of the UAV above Jezero crater. With Ingenuity now in an “operations demonstration” phase, the sixth flight was to stretch the limits of what the craft can do and learn how it can be used to scout out potential sites to explore for its robot buddy on the surface, Perseverance.

While the aircraft was performing its 150 m move to the southwest, the stream from the downward-looking navigation camera dropped a single frame. By itself, that wouldn’t have been so bad, but the glitch caused subsequent frames to come in with the wrong timestamps. This apparently confused the hell out of the flight controller, which commanded some pretty dramatic moves in the roll and pitch axes — up to 20° off normal. Thankfully, the flight controller was designed to handle just such an anomaly, and the aircraft was able to land safely within five meters of its planned touchdown. As pilots say, any landing you can walk away from is a good landing, so we’ll chalk this one up as a win for the Ingenuity team, who we’re sure are busily writing code to prevent this from happening again.

If wobbling UAVs on another planet aren’t enough cringe for you, how about a blind mechanical demi-ostrich drunk-walking up and down a flight of stairs? The work comes from the Oregon State University and Agility Robotics, and the robot in question is called Cassie, an autonomous bipedal bot with a curious, bird-like gait. Without cameras or lidar for this test, the robot relied on proprioception, which detects the angle of joints and the feedback from motors when the robot touches a solid surface. And for ten tries up and down the stairs, Cassie did pretty well — she only failed twice, with only one counting as a face-plant, if indeed she had a face. We noticed that the robot often did that little move where you misjudge the step and land with the instep of your foot hanging over the tread; that one always has us grabbing for the handrail, but Cassie was able to power through it every time. The paper describing how Cassie was trained is pretty interesting — too bad ED-209’s designers couldn’t have read it.

So this is what it has come to: NVIDIA is now purposely crippling its flagship GPU cards to make them less attractive to cryptocurrency miners. The LHR, or “Lite Hash Rate” cards include new-manufactured GeForce RTX 3080, 3070, and 3060 Ti cards, which will now have reduced Ethereum hash rates baked into the chip from the factory. When we first heard about this a few months ago, we puzzled a bit — why would a GPU card manufacturer care how its cards are used, especially if they’re selling a ton of them. But it makes sense that NVIDIA would like to protect their brand with their core demographic — gamers — and having miners snarf up all the cards and leaving none for gamers is probably a bad practice. So while it makes sense, we’ll have to wait and see how the semi-lobotomized cards are received by the market, and how the changes impact other non-standard uses for them, like weather modeling and genetic analysis.

Speaking of crypto, we found it interesting that police in the UK accidentally found a Bitcoin mine this week while searching for an illegal cannabis growing operation. It turns out that something that uses a lot of electricity, gives off a lot of heat, and has people going in and out of a small storage unit at all hours of the day and night usually is a cannabis farm, but in this case it turned out to be about 100 Antminer S9s set up on janky looking shelves. The whole rig was confiscated and hauled away; while Bitcoin mining is not illegal in the UK, stealing the electricity to run the mine is, which the miners allegedly did.

And finally, we have no idea what useful purpose this information serves, but we do know that it’s vitally important to relate to our dear readers that yellow LEDs change color when immersed in liquid nitrogen. There’s obviously some deep principle of quantum mechanics at play here, and we’re sure someone will adequately explain it in the comments. But for now, it’s just a super interesting phenomenon that has us keen to buy some liquid nitrogen to try out. Or maybe dry ice — that’s a lot easier to source.

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Hackaday Links: May 23, 2021

May 23, 2021 by 10 Comments

The epicenter of the Chinese electronics scene drew a lot of attention this week as a 70-story skyscraper started wobbling in exactly the way skyscrapers shouldn’t. The 1,000-ft (305-m) SEG Plaza tower in Shenzhen began its unexpected movements on Tuesday morning, causing a bit of a panic as people ran for their lives. With no earthquakes or severe weather events in the area, there’s no clear cause for the shaking, which was clearly visible from the outside of the building in some of the videos shot by brave souls on the sidewalks below. The preliminary investigation declared the building safe and blamed the shaking on a combination of wind, vibration from a subway line under the building, and a rapid change in outside temperature, all of which we’d suspect would have occurred at some point in the 21-year history of the building. Others are speculating that a Kármán vortex Street, an aerodynamic phenomenon that has been known to catastrophically impact structures before, could be to blame; this seems a bit more likely to us. Regardless, since the first ten floors of SEG Plaza are home to one of the larger electronics markets in Shenzhen, we hope this is resolved quickly and that all our friends there remain safe.

In other architectural news, perched atop Building 54 at the Massachusetts Institute of Technology campus in Cambridge for the last 55 years has been a large, fiberglass geodesic sphere, known simply as The Radome. It’s visible from all over campus, and beyond; we used to work in Kendall Square, and the golf-ball-like structure was an important landmark for navigating the complex streets of Cambridge. The Radome was originally used for experiments with weather radar, but fell out of use as the technology it helped invent moved on. That led to plans to remove the iconic structure, which consequently kicked off a “Save the Radome” campaign. The effort is being led by the students and faculty members of the MIT Radio Society, who have put the radome to good use over the years — it currently houses an amateur radio repeater, and the Radio Society uses the dish within it to conduct Earth-Moon-Earth (EME) microwave communications experiments. The students are serious — they applied for and received a $1.6-million grant from Amateur Radio Digital Communications (ARDC) to finance their efforts. The funds will be used to renovate the deteriorating structure.

Well, this looks like fun: Python on a graphing calculator. Texas Instruments has announced that their TI-84 Plus CE Python graphing calculator uses a modified version of CircuitPython. They’ve included seven modules, mostly related to math and time, but also a suite of TI-specific modules that interact with the calculator hardware. The Python version of the calculator doesn’t seem to be for sale in the US yet, although the UK site does have a few “where to buy” entries listed. It’ll be interesting to see the hacks that come from this when these are readily available.

Did you know that PCBWay, the prolific producer of cheap PCBs, also offers 3D-printing services too? We admit that we did not know that, and were therefore doubly surprised to learn that they also offer SLA resin printing. But what’s really surprising is the quality of their clear resin prints, at least the ones shown on this Twitter thread. As one commenter noted, these look more like machined acrylic than resin prints. Digging deeper into PCBWay’s offerings, which not only includes all kinds of 3D printing but CNC machining, sheet metal fabrication, and even injection molding services, it’s becoming harder and harder to justify keeping those capabilities in-house, even for the home gamer. Although with what we’ve learned about supply chain fragility over the last year, we don’t want to give up the ability to make parts locally just yet.

And finally, how well-calibrated are your fingers? If they’re just right, perhaps you can put them to use for quick and dirty RF power measurements. And this is really quick and really dirty, as well as potentially really painful. It comes by way of amateur radio operator VK3YE, who simply uses a resistive dummy load connected to a transmitter and his fingers to monitor the heat generated while keying up the radio. He times how long it takes to not be able to tolerate the pain anymore, plots that against the power used, and comes up with a rough calibration curve that lets him measure the output of an unknown signal. It’s brilliantly janky, but given some of the burns we’ve suffered accidentally while pursuing this hobby, we’d just as soon find another way to measure RF power.

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Hackaday Links: May 16, 2021

May 16, 2021 by 19 Comments

With the successful arrival of China’s first Mars lander and rover this week, and the relatively recent addition of NASA’s Perseverance rover and its little helicopter sidekick Ingenuity, Mars has collected a lot of new hardware lately. But while the new kids on the block are getting all the attention, spare a thought for the reliable old warhorse which has been plying Gale Crater for the better part of a decade now — Curiosity. NASA has been driving the compact-car-sized rover around Mars for a long time now, long enough to rack up some pretty severe damage to its six highly engineered wheels, thanks to the brutal Martian rocks. But if you think Curiosity will get sidelined as its wheels degrade, think again — the rover’s operators have a plan to continue surface operations that includes ripping off its own wheels if necessary. It’s a complex operation that would require positioning the wheel over a suitable rock and twisting with the steering motor to peel off the outer section of the wheel, leaving a rim to drive around on. JPL has already practiced it, but they predict it won’t be necessary until 2034 or so. Now that’s thinking ahead.

With all the upheaval caused by the ongoing and worsening semiconductor shortage, it might seem natural to expect that manufacturers are responding to market forces by building new fabs to ramp up production. And while there seems to be at least some movement in that direction, we stumbled across an article that seems to give the lie to the thought that we can build our way out of the crisis. It’s a sobering assessment, to say the least; the essence of the argument is that 20 years ago or so, foundries thought that everyone would switch to the new 300-mm wafers, leaving manufacturing based on 200-mm silicon wafers behind. But the opposite happened, and demand for chips coming from the older 200-mm wafers, including a lot of the chips used in cars and trucks, skyrocketed. So more fabs were built for the 200-mm wafers, leaving relatively fewer fabs capable of building the chips that the current generation of phones, IoT appliances, and 5G gear demand. Add to all that the fact that it takes a long time and a lot of money to build new fabs, and you’ve got the makings of a crisis that won’t be solved anytime soon.

From not enough components to too many: the Adafruit blog has a short item about XScomponent, an online marketplace for listing your excess inventory of electronic components for sale. If you perhaps ordered a reel of caps when you only needed a dozen, or if the project you thought was a done deal got canceled after all the parts were ordered, this might be just the thing for you. Most items offered appear to have a large minimum quantity requirement, so it’s probably not going to be a place to pick up a few odd parts to finish a build, but it’s still an interesting look at where the market is heading.

Speaking of learning from the marketplace, if you’re curious about what brands and models of hard drives hold up best in the long run, you could do worse than to look over real-world results from a known torturer of hard drives. Cloud storage concern Backblaze has published their analysis of the reliability of the over 175,000 drives they have installed in their data centers, and there’s a ton of data to pick through. The overall reliability of these drives, which are thrashing about almost endlessly, is pretty impressive: the annualized failure rate of the whole fleet is only 0.85%. They’ve also got an interesting comparison of HDDs and SSDs; Backblaze only uses solid-state disks for boot drives and for logging and such, so they don’t get quite the same level of thrash as drives containing customer data. But the annualized failure rate of boot SDDs is much lower than that of HDDs used in the same role. They slice and dice their data in a lot of fun and revealing ways, including by specific brand and model of drive, so check it out if you’re looking to buy soon.

And finally, you know that throbbing feeling you get in your head when you’re having one of those days? Well, it turns out that whether you can feel it or not, you’re having one of those days every day. Using a new technique called “3D Amplified Magnetic Resonance Imaging”, or 3D aMRI, researchers have made cool new videos that show the brain pulsating in time to the blood flowing through it. The motion is exaggerated by the imaging process, which is good because it sure looks like the brain swells enough with each pulse to crack your skull open, a feeling which every migraine sufferer can relate to. This reminds us a bit of those techniques that use special algorithms to detects a person’s heartbeat from a video by looking for the slight but periodic skin changes that occurs as blood rushes into the capillaries. It’s also interesting that when we spied this item, we were sitting with crossed legs, watching our upper leg bounce slightly in time with our pulse.

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Hackaday Links: May 9, 2021

May 9, 2021 by 17 Comments

Well, that de-escalated quickly. It seems like no sooner than a paper was announced that purported to find photographic evidence of fungi growing on Mars, that the planetary science and exobiology community came down on it like a ton of bricks. As well they should — extraordinary claims require extraordinary evidence, and while the photos that were taken by Curiosity and Opportunity sure seem to show something that looks a lot like a terrestrial puffball fungus, there are a lot of other, more mundane ways to explain these formations. Add to the fact that the lead author of the Martian mushroom paper is a known crackpot who once sued NASA for running over fungi instead of investigating them; the putative shrooms later turned out to be rocks, of course. Luckily, we have a geobiology lab wandering around on Mars right now, so if there is or was life on Mars, we’ll probably find out about it. You know, with evidence.

If you’re a fan of dystopic visions of a future where bloodthirsty robots relentlessly hunt down the last few surviving humans, the news that the New York Police Department decided to stop using their “DigiDog” robot will be a bit of a downer. The move stems from outrage generated by politicians and citizens alike, who dreamt up all sorts of reasons why the NYPD shouldn’t be using this tool. And use it they apparently did —  the original Boston Dynamics yellow showing through the many scuffs and dings in the NYPD blue paint job means this little critter has seen some stuff since it hit the streets in late 2020. And to think — that robot dog was only a few weeks away from filing its retirement papers.

Attention, Commodore fans based in Europe: the Commodore Users Europe event is coming soon. June 12, to be precise. As has become traditional, the event is virtual, but it’s free and they’re looking for presenters.

In a bid to continue the grand Big Tech tradition of knowing what’s best for everyone, Microsoft just announced that Calibri would no longer be the default font in Office products. And here’s the fun part: we all get to decide what the new default font will be, at least ostensibly. The font wonks at Microsoft have created five new fonts, and you can vote for your favorite on social media. The font designers all wax eloquent on their candidates, and there are somewhat stylized examples of each new font, but what’s lacking is a simple way to judge what each font would actually look like on a page of English text. Whatever happened to “The quick brown fox” or even a little bit of “Lorem ipsum”?

And finally, why are German ambulances — and apparently, German medics — covered in QR codes? Apparently, it’s a way to fight back against digital rubberneckers. The video below is in German, but the gist is clear: people love to stop and take pictures of accident scenes, and smartphones have made this worse, to the point that emergency personnel have trouble getting through to give aid. And that’s not to mention the invasion of privacy; very few accident victims are really at their best at that moment, and taking pictures of them is beyond rude. Oh, and it’s illegal, punishable by up to two years in jail. The idea with the QR codes is to pop up a website with a warning to the rubbernecker. Our German is a bit rusty, but we’re pretty sure that translates to, “Hey idiot, get back in your frigging car!” Feel free to correct us on that.

[Editor’s note: “Stop. Rubbernecking kills”.]

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Hackaday Links: May 2, 2021

May 2, 2021 by 3 Comments

Mars is getting to be a busy place, what with helicopters buzzing around and rovers roving all about the place. Now it’s set to get a bit more crowded, with the planned descent of the newly-named Chinese Zhurong rover. Named after the god of fire from ancient Chinese mythology, the rover, which looks a little like Opportunity and Spirit and rides to the surface aboard something looking a little like the Viking lander, will carry a suite of scientific instruments around Utopia Planitia after it lands sometime this month. Details are vague; China usually plays its cards close to the vest, and generally makes announcements only when a mission is a fait accompli. But it appears the lander will leave its parking orbit, which it entered back in February, sometime this month. It’s not an easy ride, and we wish Zhurong well.

Speaking of space, satellites don’t exactly grow on trees — until they do. A few groups, including a collaboration between UPM Plywood and Finnish startup Arctic Astronautics, have announced intentions to launch nanosatellites made primarily of wood. Japanese logging company Sumitomo Forestry and Kyoto University also announced their partnership, formed with the intention to prove that wooden satellites can work. While it doesn’t exactly spring to mind as a space-age material, wood does offer certain advantages, including relative transparency to a wide range of the RF spectrum. This could potentially lead to sleeker satellite designs, since antennae and sensors could be located inside the hull. Wood also poses less of a hazard than a metal spaceframe does when the spacecraft re-enters the atmosphere. But there’s one serious disadvantage that we can see: given the soaring prices for lumber, at least here in the United States, it may soon be cheaper to build satellites out of solid titanium than wood.

If the name Ian Davis doesn’t ring a bell with you, one look at his amazing mechanical prosthetic hand will remind you that we’ve been following his work for a while now. Ian suffered a traumatic amputation of the fingers of his left hand, leaving only his thumb and palm intact, and when his insurance wouldn’t pay for a prosthetic hand, he made his own. Ian has gone through several generations, each of which is completely mechanical and controlled only by wrist movements. The hands are truly works of mechanical genius, and Ian is now sharing what he’s learned to help out fellow hand-builders. Even if you’re not building a hand, the video is well worth watching; the intricacy of the whiffle-tree mechanism used to move the fingers is just a joy to behold, and the complexity of movement that Ian’s hand is capable of is just breathtaking.

If mechanical hands don’t spark your interest, then perhaps the engineering behind top fuel dragsters will get you going. We’ll admit that most motorsports bore us to tears, even with the benefit of in-car cameras. But there’s just something about drag cars that’s so exciting. The linked video is a great dive into the details of the sport, where engines that have to be rebuilt after just a few seconds use, fuel flows are so high that fuel lines the size of a firehouse are used, and the thrust from the engine’s exhaust actually contributes to the car’s speed. There’s plenty of slo-mo footage in the video, including great shots of what happens to the rear tires when the engine revs up. Click through the break for more!

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Hackaday Links: April 25, 2021

April 25, 2021 by 14 Comments

There’s much news from the Jezero Crater on Mars this week, and all of it was good. Not only did the Ingenuity helicopter make history by making the first powered, controlled flight of an aircraft on another planet, it made a second longer, more complex flight just a couple of days later. This time, the autonomous rotorwing craft flew to a higher altitude than the maiden flight, hovered for a bit longer, and made a lateral move before landing safely again on the surface. Three more flights of increasing complexity (and risk) are scheduled over the next two weeks, with the next set to happen early Sunday morning. I have to admit that even though the Ingenuity tech demonstration seemed a little like a publicity stunt when I first heard about it, especially when compared to the Perseverance’s main mission of searching for evidence of life on Mars, the Ingenuity team’s successes have made a believer out of me.

Speaking of technology demonstrations, NASA fired up the MOXIE experiment aboard Perseverance for the first time. Intended to explore the possibility of producing oxygen from the thin carbon dioxide-rich Martian atmosphere, the Mars Oxygen In-Situ Resource Utilization Experiment made about 5.4 grams of oxygen total at a rate of about 6 grams an hour. We detailed the technology MOXIE uses, called solid-oxide electrolysis, which depends on a scandium-stabilized zirconium oxide ceramic electrolyte to strip the oxygen from superheated carbon dioxide using an electric current. Should the technology prove itself over the planned total of ten MOXIE runs over the next few months, a scaled up version of the device could someday land on Mars and produce the estimated 55 metric tons of oxygen needed to fuel a return trip from a crewed mission.

By now we’ve all heard about the global semiconductor shortage, or perhaps felt the pinch ourselves while trying to procure parts for a build. It’s easy to count the crunch as yet another follow-on from the COVID-19 shutdowns and the logistics woes the pandemic begat, so one might have hope that with lockdowns easing up around the world, the shortage will soon be over as manufacturers ramp up production. But not so fast — it looks like the machines needed to make the chips are the latest victims of the shortage. According to Nikkei Asia, wire bonding machines, wafer dicers, and laser drilling machines are all in short supply, with orders for new machines booked out for a year. Like toilet paper this time last year, chip makers are hoarding machines, ordering 50 or 100 of them at a time, in the hopes of having enough to meet production goals. And when machines are available, travel restrictions are making it difficult to get on-site installation and support from factory reps. The bottom line — this isn’t over yet, not by a long shot.

We all know the Stack Overflow memes, and few of us who are being honest haven’t squirmed a bit when thinking about just how screwed we’d be without being able to copy a bit of code to get us past that rough part in a project. But just how often do people copy code from Stack Overflow? Quite a lot, actually, if SO’s analysis of the use of copy commands on their pages is to be believed. For two weeks, SO monitored the number of times the Ctrl-C (or Command-C, if that’s your jam) key combination was pressed. They toted up over 40 million copies, most often from the answers to questions and almost always from the code blocks within them. We suppose none of this is exactly unexpected — memes are memes for a reason, after all — but what we found surprising is that one in four visitors to Stack Overflow copied something within five minutes of loading a page. Being charitable, we’d say the speed with which coders accept someone else’s work is an indication that maybe they were almost at an answer themselves and just needed a little reminder. On the other hand, it could be a sign of separation driving them to get something working.

And finally, while we know we’ve recommended videos from Grady at Practical Engineering recently, we couldn’t help but plug another of his videos as a must-watch. This time, Grady tackles the Suez Canal blockage, and he presents it in the same dispassionate, informed way that he previously handled the engineering roots of the Texas blackouts. If you think the Ever Given grounding was just a case of poor seamanship, think again — Grady makes a compelling case for possible hydrodynamic causes of the incident, including “squatting” and the bank effect. He also speculates on the geotechnical forces that held the ship fast, in the process of which he helpfully introduces the concept of dilatancy and how it explains the way your feet seem to “dry out” a zone around them as you walk across the beach.

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