The Last Days Of The Wild West

April 10, 2021 by Elliot Williams 21 Comments

We loved it a few weeks ago when an international team of hackers managed to record and decode telemetry and images from SpaceX launches. And now it looks like SpaceX has started encrypting it all in response. Booo!

Decoding satellite and other space ship transmissions has been a great hacker pastime. Most recently, we’ve seen a group working on listening in to the Chinese Tianwen-1 Mars probe shortly after its launch, but listening to the Deep Space Network or even just decoding weather satellite broadcasts can give folks a reason to stretch their radio muscles.

We understand that SpaceX runs some contract missions for US gov’t agencies that don’t appreciate leaking info about their satellite’s whereabouts, but for non-secret missions, we don’t see the harm in letting the amateurs listen in over their shoulder. Maybe they’re doing it for PR reasons if/when something goes badly wrong?

Whatever the reasons, it’s a shame. Space has been open to hackers for a long time, knowingly in the case of amateur satellites, and unknowingly in the case of many other satellites which until the mid-90s had command channels that were unencrypted. (I’ll have to stick with “unnamed sources” on this one, but I do know a person who has rotated a satellite that he or she didn’t own.) There’s a lot to be learned by listening to signals from above, and while you can still decode weather satellite data yourself, it’s not quite as sexy as downloading images straight from a Falcon 9.

The cool hand for SpaceX to have played would have been to say “of course — we broadcast unencrypted as PR to our biggest fans” but it looks instead like they simply didn’t think that anyone would be listening in, and this caught them by surprise and they panicked. In 2021, with something as complicated as a space mission, that’s a little bit embarrassing. Anyway, to those of you who managed to get in before encryption, kudos!

When The Right Tool Is Wrong

April 3, 2021 by Elliot Williams 76 Comments

I’m a firm believer in using the right tool for the job. And one of the most fantastic things about open-source software tools is that nothing stops you from trying them all. For instance, I’ve been going back and forth between a couple, maybe three, CAD/CAM tools over the past few weeks. They each have their strengths and weaknesses, and so if I’m doing a simpler job, I use the simpler software, because it’s quicker and, well, simpler. But I’ve got to cut it out, at least for a while, and I’ll tell you why.

The first of the packages is FreeCAD, and it’s an extremely capable piece of CAD/CAM software. It can do everything, or so it seems. But it’s got a long shallow learning curve, and I’m only about halfway up. I’m at the stage where I should be hammering out simple “hello world” parts for practice. I say, I should be.

Fortunately/unfortunately, some Hackaday readers introduced me to KrabzCAM through the comments. It’s significantly less feature-full than FreeCAD, but it gets the job of turning your wife’s sketches of bunnies into Easter decorations done in a jiffy. For simple stuff like that, it’s a nice simple tool, and is the perfect fit for 2D CAM jobs. It’s got some other nice features, and it handles laser engraving nicely as well. And that’s the problem.

Doing the simple stuff with KrabzCAM means that when I do finally turn back to FreeCAD, I’m working on a more challenging project — using techniques that I’m not necessarily up to speed on. So I’ll put the time in, but find myself still stumbling over the introductory “hello world” stuff like navigation and project setup.

I know — #first-world-hacker-problems. “Poor Elliot has access to too many useful tools, with strengths that make them fit different jobs!” And honestly, I’m stoked to have so many good options — that wasn’t the case five years ago. But in this case, using the right tool for the job is wrong for me learning the other tool.

On reflection, this is related to the never-try-anything-new-because-your-current-tools-work-just-fine problem. And the solution to that one is to simply bite the bullet and stick it out with FreeCAD until I get proficient. But KrabzCAM works so well for those small 2D jobs…

A hacker’s life is hard.

NFTs Are The Hope For A New Tomorrow!

April 1, 2021 by Jenny List 54 Comments

Here at Hackaday, we’re always working as hard as we can to bring you the latest and most exciting technologies, and like so many people we’ve become convinced that the possibilities offered by the rise of the Blockchain present unrivaled opportunities for humanity to reinvent itself unfettered by the stifling regulations of a dying system. This is why today we’ve decided to join in with the digital cognoscenti and celebrities embracing Non-Fungible Tokens, or NFTs, as a new promise of non-corporeal digital investment cryptoasset that’s taking the world by storm.

Crypto Non-Fungible Investment Gains!

Imagine for a minute, yourself owning a very expensive car. Skievl, CC BY-SA 4.0.

An NFT is a digital token representing something in the real world, and coupled to a unique ID held in a secure entry in the Blockchain. It’s non-fungible, which means that it’s unique and not interchangeable in the manner of a traditional old-style cryptoasset such as Bitcoin. As it allows a real-world object to be tokenised in digital form it represents a way to own something that provides an irrefutable connection to it as as a digital cryptoasset.

It’s a complex system that’s maybe too difficult to explain fully in a single article, but think of an NFT as a way to invest in a cryptoasset in digital form with its uniqueness guaranteed by Blockchain security, without having the inconvenience of physically owning it. Instead your NFT is safely held on a server on the Internet, and can’t be physically stolen as it would from a bank vault because it has the Blockchain cryptosecurity baked in.

Non Fungible Blockchain Cryptoassets!

You don't own this. Yet. — You don’t own this. Yet.

NFTs have so far found a space in the creative markets, where they have provided a revolutionary opportunity for artists to expand their sales in the digital realm by selling NFTs of their work. A struggling artist can now access buyers all over the world, who can in turn now invest with confidence in creative talent to which they would never otherwise be exposed. It’s a win-win situation in which both cryptoinvestor and artist benefit from The Power of the Blockchain.

Hackaday is excited to offer a once-in-a-lifetime chance to acquire a Blockchain-cryptosecured NFT representing one of our own articles; our first ever NFT is the only officially sanctioned digital copy of a Hackaday article presenting a novel method of handling toilet paper shortages. The original article will continue to exist on Hackaday.com with all rights reserved, but we will not make any other NFTs of it. We may also decide to update the original article to let everyone know you are the lucky owner of the only digital copy of this piece of greatness. That’s right, this NFT will let you prove you own a screenshot!

Having today sold you on the incredible cryptoinvestment opportunity offered by NFTs, we’ll be back on another date with a more sober and in-depth technical examination of the technology behind them. Meanwhile should our brief foray into NFTs garner any interest (and we really hope it does not), we will donate proceeds to the excellent Girls Who Code, a truly solid investment with a tangible bright future.

Thanks [Micah Scott] for some NFT consultancy during the making of this piece.

Hackaday Forced Into Light Mode

April 1, 2021 by Elliot Williams 95 Comments

Hackaday has always been dark mode. Gray10 is less jarring when you’re burning the midnight oil on a project, so we give you a lot of it. Fifteen years ago, it was called “reverse video” or “trog mode“, and we were the freaks. We were doing it wrong. We had the colors “backwards”. Dark mode used to be edgy, outré, but dare we say it, a bit sexy.

Hackaday … QuickBooks. Just sayin’.
They even ripped our highlight yellow!

Flash forward, and everyone has come over to the dark side. Facebook has a dark mode. Google has dark mode. Across the Microsoft empire, from Windows 10 to GitHub, you can live your life in the dark. Heck, even the White House has a dark mode! (They call it high-contrast mode, but they’re not fooling anyone.)

Dark mode here, dark mode there. It’s mainstream. Dark mode has become corporate cool which is nobody’s idea of cool.

We’re not saying that all of the aforementioned institutions are biting the Hackaday style, but, well, they’re all biting our style. Where were they when we were the only website on the whole darn Internet with a sensible background color? Huh? Dark-mode-come-latelys!

But Hackaday doesn’t rest on its laurels. We have our fingers on the pulse on the modern hacker. Where previously you would be up late at night researching Hackaday for juicy nuggets of communal wisdom to help out with your current hack, you’re probably “telecommuting” these days — a euphemism for working on your private projects even while the fiery ball is still in the sky. (Wink, wink, nudge, nudge.) It’s only natural that you’d want a lighter background color to match your new lifestyle. We hear you!

So we present you, Hackaday Light Mode™. Enjoy!

[Editor’s note: For historical accuracy, we had phosphor green headings in the very beginning, in place of the jarring white. If you want to relive those glory days of yore, or just to go back to Hackaday in dark mode, there’s always CSS scripting.]

JIT Vs. AM: Is Additive Manufacturing The Cure To Fragile Supply Chains?

April 1, 2021 by Dan Maloney 46 Comments

As fascinating and frustrating as it was to watch the recent Suez canal debacle, we did so knowing that the fallout from it and the analysis of its impact would be far more interesting. Which is why this piece on the potential of additive manufacturing to mitigate supply chain risks caught our eye.

We have to admit that a first glance at the article, by [Davide Sher], tripped our nonsense detector pretty hard. After all, the piece appeared in 3D Printing Media Network, a trade publication that has a vested interest in boosting the additive manufacturing (AM) industry. We were also pretty convinced going in that, while 3D-printing is innovative and powerful, even using industrial printers it wouldn’t be able to scale up enough for print parts in the volumes needed for modern consumer products. How long would it take for even a factory full of 3D-printers to fill a container with parts that can be injection molded in their millions in China?

But as we read on, a lot of what [Davide] says makes sense. A container full of parts that doesn’t arrive exactly when they’re needed may as well never have been made, while parts that are either made on the factory floor using AM methods, or produced locally using a contract AM provider, could be worth their weight in gold. And he aptly points out the differences between this vision of on-demand manufacturing and today’s default of just-in-time manufacturing, which is extremely dependent on supply lines that we now know can be extremely fragile.

So, color us convinced, or at least persuaded. It will certainly be a while before all the economic fallout of the Suez blockage settles, and it’ll probably longer before we actually see changes meant to address the problems it revealed. But we would be surprised if this isn’t seen as an opportunity to retool some processes that have become so optimized that a gust of wind could take them down.

Putting Your Time In

March 27, 2021 by Elliot Williams 28 Comments

I was absolutely struck by a hack this week — [Adam Bäckström]’s amazing robot arm built with modified hobby servos. Basically, he’s taken apart and re-built some affordable off-the-shelf servo motors, and like the 6-Million-Dollar Man, he’s rebuilt them better, stronger, faster. OK, and smoother. We have the technology.

The results are undeniably fantastic, and enable the experienced hacker to get champagne robot motion control on a grape-juice budget by employing some heavy control theory, and redundant sensors to overcome geartrain backlash, which is the devil of cheap servos. But this didn’t come out of nowhere. In his writeup, [Adam] starts off with “You could say this project started when I ordered six endless servos in middle school, more than 15 years ago.” And it shows.

Go check out this video of his first version of the modified servos, from a six-axis arm he built in 2009(!). He’s built in analog position sensors in the motors, which lets him control the speed and makes it work better than any other hobby servo arm you’ve ever seen, but there’s still visible backlash in the gears. A mere twelve years later, he’s got magnetic encoders on the output and a fast inner loop compensates for the backlash. The result is that the current arm moves faster and smoother, while retaining accuracy.

Twelve years. I assume that [Adam] has had some other projects on his plate as well, but that’s a long term project by any account. I’m stoked to see his work, not the least because it should help a lot of others who are ready to step up their desktop servo-arm projects. But the real take-home lesson here is that if you’ve got a tough problem that you’re hacking on, you don’t have to get it done this weekend. You don’t have to get it done next weekend either. Keep hammering on it as long as you need, but keep on hammering. When you get it done, the results will be all the better for the long, slow, brewing time. What’s the longest project that you’ve ever worked on?

Machinist’s Accuracy Vs. Woodworker’s Precision

March 20, 2021 by Elliot Williams 73 Comments

There are at least two ways of making parts that fit together exactly. The first way is the Cartesian way, and the machinists way. Imagine that you could specify the size of both the hole and the peg that you’d like to put into it. Just make sure your tolerances are tight enough, and call out a slightly wider hole. Heck, you can look up the type of fit you’d like in a table, and just specify that. The rest is a simple matter of machining the parts accurately to the right tolerances, and you’re done.

The machinist’s approach lives and dies on that last step — making the parts accurately fit the measure. Contrast the traditional woodworker’s method, or at least as it was taught to me, of just making the parts fit each other in the first place. This is the empirical way, the Aristotelian way if you will. You don’t really have to care if the two parts are exactly 30.000 mm wide, as long as they’re precisely the same length. And woodworkers have all sorts of clever tricks to make things the same, or make them fit, without measuring at all. Their methods are heavy on the jigs and the clever set-ups, and extraordinarily light on the calipers. To me, coming from a “measure carefully, and cut everything to measure” background, these ways of working were a revelation.

This ends up expressing perfectly the distinction between accuracy and precision. Sometimes you need to hit the numbers right on, and other times, you just need to get the parts to fit. And it’s useful to know which of these situations you’re actually in.

Of course, none of this is exclusive to metal or wood, and I’m actually mentioning it because I find myself using ideas that I learned in one context and applying them in the other. For instance, if you need sets of holes that match each other perfectly, whether in metal or wood, you get that precision for free by drilling through two sheets at one time, or by making a template — no measuring needed. Instead of measuring an exact distance from a feature, if all you care about is two offsets being the same, you can find a block of scrap with just about the right width, and use that to mark both distances. Is it exactly 1.000″ wide? Nope. But can you use this to mark identical locations? Yup.

You can make surprisingly round objects in wood by starting with a square, and then precisely marking the centers of the straight faces, and then cutting off the corners to get an octagon. Repeat with the centers and cutting until you can’t see the facets any more. Then hit it with sandpaper and you’re set. While this won’t make as controlled a diameter as would come off a metal lathe, you’d be surprised how well this works for making round sheet-aluminum circles when you don’t care so much about the diameter. And the file is really nothing other than the machinist’s sandpaper (or chisel?).

I’m not advocating one way of working over the other, but recognizing that there are two mindsets, and taking advantage of both. There’s a certain freedom that comes from the machinist’s method: if both parts are exactly 25.4 mm long, they’re both an accurate inch, and they’ll match each other. But if all you care about is precise matching, put them in the vise and cut them at the same time. Why do you bother with the calipers at all? Cut out the middle-man!