Leading Edge Erosion: When Precipitation Destroys Wind Turbine Blades

October 5, 2022 by Maya Posch 85 Comments

Erosion is all around us, from the meandering course of rivers and other waterways, to the gradual carving out of channels in even the toughest mountains, and the softening of features in statues. Yet generally we expect erosion from precipitation to be gradual and gentle, taking decades to make a noticeable difference. This of course takes into account gentle flows and the soft pitter-patter of rain on stone, not turbine blades passing through the air at many times the terminal velocity of rain drops of up to 9 m/s.

As wind turbines have increased in size and diameter of their blades, this has noticeably increased the speed of especially the blade tips. With more and more wind turbine blade tips now exceeding speeds of 100 m/s, this has also meant a significant increase in the impact of rain drops, hail and other particulates on the lifespan of these turbine blades. As comparison, 100 m/s is 360 km/h (224 mph), which is only slightly slower than the top speed of a Formula 1 car.

The effect of turbine blade leading edge erosion (LEE) not only decreases aerodynamic efficiency, but also invites premature failure. Over the past years, special coatings and leading edge tapes have been developed that act as sacrificial surfaces, but as wind turbines only keep getting larger, so does the effect of LEE. Beyond simply replacing LE tape every year on every turbine, what other options are there?

Continue reading “Leading Edge Erosion: When Precipitation Destroys Wind Turbine Blades” →

The State Of The SBC Interface Ecosystem, Is It Time To Design A Standard?

October 5, 2022 by Jenny List 132 Comments

We are spoiled for choice when it comes to single board computers, whether they be based around a microcontroller or a more capable SoC capable of running an operating system such as GNU/Linux. They can be had from well-established brands such as Arduino, Adafruit, or Raspberry Pi, or from a Wild West of cheaper Far Eastern modules carrying a plethora of different architectures.

Everyone has their own favourite among them, and along with that comes an ecosystem of operating systems and software development environments. There’s another aspect to these boards which has evolved; certain among them have become de facto interface connector standards for hardware peripherals. Do these standards make any sense? Let’s talk about that.

Continue reading “The State Of The SBC Interface Ecosystem, Is It Time To Design A Standard?” →

2022 Hackaday Supercon Speakers Will Inspire You

October 4, 2022 by Elliot Williams 10 Comments

The return of Supercon is taking place in just a month. We’ve got 45 fantastic talks and workshops planned for the three-day weekend, and they are as varied and inspiring as the Hackaday community itself. From molecules to military connectors, here’s an even dozen talks to whet your appetite.

Supercon is the Ultimate Hardware Conference and you need to be there! We’ll continue to announce speakers and workshops over the next couple weeks. Supercon will sell out so get your tickets now before it’s too late. And stay tuned for the next round of talk reveals next week! Continue reading “2022 Hackaday Supercon Speakers Will Inspire You” →

Thank Magnesium For Water-Activated Batteries

October 4, 2022 by Lewin Day 16 Comments

Most of the batteries we use these days, whether rechargeable or not, are generally self-contained affairs. They come in a sealed package, with the anode, cathode, and electrolyte all wrapped up inside a stout plastic or metal casing. All the reactive chemicals stay inside.

However, a certain class of magnesium batteries are manufactured in a dry, unreactive state. To switch these batteries on, all you need to do is add water! Let’s take a look at these useful devices, and explore some of their applications.

Continue reading “Thank Magnesium For Water-Activated Batteries” →

Big Brother Or Dumb Brother? Bus Drivers In Beijing Are Forced To Wear “Emotional Monitors”

October 3, 2022 by Lewin Day 64 Comments

Humans aren’t always great at respecting each other’s privacy. However, common sense says there’s a clear boundary when it comes to the thoughts in one’s own head and the feelings in one’s heart.

For bus drivers in Beijing though, it seems that’s no longer the case. These professional drivers are now being asked to wear emotional monitors while on the job, raising concerns from both legal and privacy advocates. But the devices aren’t really anything more than workout monitors, and whether they can actually make good on their Orwellian promise remains to be seen.

In Your Head, In Your Head!

The monitoring wristbands have been rolled out to some of Beijing’s long-distance bus drivers. Credit: Cypp0847, CC-BY-SA-4.0

When George Orwell wrote 1984, it was only 1949. However, he was able to foresee a world in which surveillance was omnipresent and inescapable. He also envsioned the concept of thoughtcrime, where simply contemplating the wrong things could get you in serious trouble with the authorities.

As we all know, Orwell was way off – these predictions didn’t become reality until well into the 2000s. In the latest horrifying development, technologies now exist that claim to be able to monitor one’s emotional state. Now, China’s transportation sector is rushing to push them on their workforces.

Long-distance bus drivers in Beijing are now being told to wear electronic wristbands when on the job. These wristbands claim to be able to capture the wearer’s emotional state, monitoring it on behalf of the employer. The scheme was the idea of the Beijing Public Transport Holding Group. The state-run organization claims the technology is intended for the safety of the public, and a trial of the wristbands began in July this year. Continue reading “Big Brother Or Dumb Brother? Bus Drivers In Beijing Are Forced To Wear “Emotional Monitors”” →

Lithium-Ion Batteries Are Easy To Find

October 3, 2022 by Arya Voronova 43 Comments

In the first article, I’ve given you an overview of Lithium-Ion batteries and cells as building blocks for our projects, and described how hackers should treat their Lithium-Ion cells. But what if you don’t have any LiIon cells yet? Where do you get LiIon cells for your project?

Taking laptop batteries apart, whether the regular 18650 or the modern pouch cell-based ones, remains a good avenue – many hackers take this road and the topic is extensively covered by a number of people. However, a 18650 cell might not fit your project size-wise, and thin batteries haven’t quite flooded the market yet. Let’s see what your options are beyond laptops. Continue reading “Lithium-Ion Batteries Are Easy To Find” →

Hackaday Links: October 2, 2022

October 2, 2022 by Dan Maloney 22 Comments

“Necessity is the mother of invention,” or so the saying goes. We’ve never held to that, finding that laziness is a much more powerful creative lubricant. And this story about someone who automated their job with a script is one of the best examples of sloth-driven invention since the TV remote was introduced. If we take the story at face value — and it’s the Internet, so why wouldn’t we? — this is a little scary, as the anonymous employee was in charge of curating digital evidence submissions for a law firm. The job was to watch for new files in a local folder, manually copy them to a cloud server, and verify the file with a hash to prove it hasn’t been tampered with and support the chain of custody. The OP says this was literally the only task to perform, so we can’t really blame them for automating it with a script once COVID shutdowns and working from home provided the necessary cover. But still — when your entire job can be done by a Windows batch file and some PowerShell commands while you play video games, we’re going to go out on a limb and say you’re probably underemployed.

People have been bagging on the US Space Force ever since its inception in 2019, which we think is a little sad. It has to be hard being the newest military service, especially since it branched off of the previously newest military service, and no matter how important its mission may be, there’s still always going to be the double stigmas of being both the new kid on the block and the one with a reputation for digging science fiction. And now they’ve given the naysayers yet more to dunk on, with the unveiling of the official US Space Force service song. Every service branch has a song — yes, even the Army, and no, not that one — and they all sound appropriately martial. So does the Space Force song, but apparently people have a problem with it, which we really don’t get at all — it sounds fine to us.

Continue reading “Hackaday Links: October 2, 2022” →