The Real World Strikes Back

February 12, 2022 by Elliot Williams 17 Comments

My son was into “Secret Coders“, a graphic novel series wherein a pair of kids discover and thwart a plot to take over the world by learning to program in the LOGO computer language. When I told him that these “turtle bots” were originally actually real physical things, he wanted one. So we built one out of some nice geared DC motors I had lying around.

A turtle bot has essentially three jobs: move forward in a straight line a controlled distance, turn a given number of degrees, and raise and lower a pen. If you’re already screaming “use stepper motors!” at your screen, well, you’re probably right. But I had these nice Faulhaber/Micromo geared motors with encoders that were just collecting dust in the closet, so I used ’em. And because of that, the robot stumbles on two of its three goals in life — the servo pen lifter works just fine.

Perfectly matched DC motors don’t exist. Of course I knew this, because I’ve built bots with DC motors before. But they’ve all had complex control mechanisms and/or feedback that made it moot. Not here. This bot needs to drive perfectly straight without any lines to guide it or more interesting navigation algorithms.

We spent a good half hour driving it around in not-quite-but-almost squares, tweaking each side’s PWMs, running the motors backwards for short bursts to brake the wheels, and generally trying to map degrees of rotation to milliseconds of motor drive. And you know what, my son enjoyed it. The concepts were simple enough for a second grader, and guessing the right PWM values was like a game. When we finally got it good enough, there was a small celebration.

Of course I know that what it really needs is encoder feedback. I installed those encoder gearmotors on purpose after all. But dealing with quadrature and probably a PID loop to control and sync the two sides is not for my son, at least not for another couple years. (They do learn closed-loop control theory in fourth grade these days, right?) I’ll have to do that all offline some night while he’s sleeping.

But I hope he’ll remember the lessons learned from stabbing at it the naive way. Abstractions are great, but no two motors are ever perfectly alike. You’d think you could just calibrate it out, but the motors differ in driven and coasting behavior, so you’ve got a lot more calibrating to do than you think at first. The real world is tough, and although it’s important to have theory and ideas and abstractions to guide you, you’re going to have to tweak to make it work when the wheels hit the floor. But also that it’s fun to do so, and super rewarding when it finally draws a wonky square.

Pick And Place Hack Chat Reveals Assembly Secrets

February 11, 2022 by Tom Nardi 9 Comments

These days we’ve got powerful free tools to do CAD and circuit design, cheap desktop 3D printers that can knock out bespoke enclosures, and convenient services that will spin up a stack of your PCBs and send them hurtling towards your front door for far less than anyone could have imagined. In short, if you want to build your own professional-looking gadgets, the only limit is your time and ambition. Well, assuming you only want to build a few of them, anyway.

Once you start adding some zeros to the number of units you’re looking to produce, hand assembling PCBs quickly becomes a non-starter. Enter the pick and place machine. This wonder of modern technology can drop all those microscopic components on your board in a fraction of the time it would take a human, and never needs to take a bathroom break. This week Chris Denney stopped by the Hack Chat to talk about these incredible machines and all the minutiae of turning your circuit board design into a finished product.

Chris is the Chief Technology Officer (CTO) of Worthington Assembly, a quick turn electronics manufacturer in South Deerfield, Massachusetts that has been building and shipping custom circuit boards since 1974. He knows a thing or two about PCB production, and looking to help junior and mid-level engineers create easier to manufacture designs, he started the “Pick, Place, Podcast” when COVID hit and in-person tours of the facility were no longer possible. Now he says he can tell when a board comes from a regular listener by how many of his tips make it into the design.

So what should you be doing to make sure your board assembly goes as smoothly as possible? Chris says a lot of it is pretty common sense stuff, like including clear polarity indicators, having a legible silkscreen, and the use of fiducial markers. But some of the tips might come as something of a surprise, such as his advice to stick with the classic green solder mask. While modern board houses might let you select from a rainbow of colors, the fact is that green is what most equipment has been historically designed to work with.

That black PCB might look slick, but can confuse older pick and place machines or conveyors which were designed with the reflectivity of the classic green PCB in mind. It also makes automated optical inspection (AOI) much more difficult, especially with smaller component packages. That said, other colors such as white and red are less of a problem and often just require some fine tuning of the equipment.

He also pulled back the curtain a bit on how the contract manufacturing (CM) world works. While many might have the impression that the PCB game has moved overseas, Chris says orders of less than 10,000 units are still largely handheld by domestic CMs to minimize turnaround time. He also notes that many assembly houses are supported almost entirely by a few key accounts, so while they may be juggling 50 customers, there’s usually just two or three “big fish” that provide 80% of their business. With such a tight-knit group, he cautions CMs can be a bit selective; so if a customer is difficult to work with they can easily find themselves on the short end of the stick.

While the Hack Chat is officially only scheduled for an hour, Chris hung out for closer to three, chatting with community members about everything and anything to do with electronic design and production. His knowledge and passion for the subject was readily apparent, and we’re glad he was able to make time in his schedule to join us.

The Hack Chat is a weekly online chat session hosted by leading experts from all corners of the hardware hacking universe. It’s a great way for hackers connect in a fun and informal way, but if you can’t make it live, these overview posts as well as the transcripts posted to Hackaday.io make sure you don’t miss out.

Hackaday Podcast 155: Dual Integrating Spheres, More Magnetic Switches, PlottyBot, Red Hair In Your Wafers

February 11, 2022 by Tom Nardi 2 Comments

This week Hackaday Editor-in-Chief Elliot Williams and Managing Editor Tom Nardi take a close look at two pairs of projects that demonstrate the wildly different approaches that hackers can take while still arriving at the same conclusion. We’ll also examine the brilliant mechanism that the James Webb Space Telescope uses to adjust its mirrors, and marvel over a particularly well-developed bot that can do your handwriting for you. The finer points of living off home-grown algae will be discussed, and by the end of the show, you’ll learn the one weird trick to stopping chip fabs in their tracks.

Take a look at the links below if you want to follow along, and as always, tell us what you think about this episode in the comments!

Direct Download (~70 MB)

Continue reading “Hackaday Podcast 155: Dual Integrating Spheres, More Magnetic Switches, PlottyBot, Red Hair In Your Wafers” →

This Week In Security: Zimbra, Lockbit 2, And Hacking NK

February 11, 2022 by Jonathan Bennett 9 Comments

Unknown attackers have been exploiting a 0-day attack against the Zimbra e-mail suite. Researchers at Volexity first discovered the attack back in December of last year, detected by their monitoring infrastructure. It’s a cross-site scripting (XSS) exploit, such that when opening a malicious link, the JavaScript running on the malicious page can access a logged-in Zimbra instance. The attack campaign uses this exploit to grab emails and attachments and upload them to the attackers. Researchers haven’t been able to positively identify what group is behind the attacks, but a bit of circumstantial evidence points to a Chinese group. That evidence? Time zones. The attacker requests all use the Asia/Hong_Kong time zone, and the timing of all the phishing emails sent lines up nicely with a work-day in that time zone.

Zimbra has responded, confirming the vulnerability and publishing a hotfix for it. The campaign seems to have been targeted specifically against European governments, and various media outlets. If you’re running a Zimbra instance, make sure you’re running at least 8.8.15.1643980846.p30-1.

LockBit 2.0

Because security professionals needed something else to keep us occupied, the LockBit ransomware campaign is back for a round two. This is another ransomware campaign run in the as-a-Service pattern — RAAS. LockBit 2 has caught enough attention, that the FBI has published a FLASH message (PDF) about it. That’s the FBI Liaison Alert System, in the running for the worst acronym. (Help them figure out what the “H” stands for in the comments below!)

Like many other ransomware campaigns, LockBit has a list of language codes that trigger a bail on execution — the Eastern European languages you would expect. Ransomware operators have long tried not to poison their own wells by hitting targets in their own back yards. This one is being reported as also having a Linux module, but it appears that is limited to VMWare ESXi virtual machines. A series of IoCs have been published, and the FBI are requesting any logs, ransom notes, or other evidence possibly related to this campaign to be sent to them if possible. Continue reading “This Week In Security: Zimbra, Lockbit 2, And Hacking NK” →

Sergiy Nesterenko giving his Remoticon 2021 talk

Remoticon 2021 // Sergiy Nesterenko Keeps Hardware Running Through Lightning And Cosmic Rays

February 10, 2022 by Robin Kearey 1 Comment

Getting to space is hard enough. You have to go up a few hundred miles, then go sideways really fast to enter orbit. But getting something into space is one thing: keeping a delicate instrument working as it travels there is quite another. In his talk at Remoticon 2021, [Sergiy Nesterenko], former Radiation Effects Engineer at SpaceX, walks us through all the things that can destroy your sensitive electronics on the way up.

The trouble already starts way before liftoff. Due to an accident of geography, several launch sites are located in areas prone to severe thunderstorms: not the ideal location to put a 300-foot long metal tube upright and leave it standing for a day. Other hazards near the launch pad include wayward wildlife and salty spray from the ocean.

Those dangers are gone once you’re in space, but then suddenly heat becomes a problem: if your spacecraft is sitting in full sunlight, it will quickly heat up to 135 °C, while the parts in the shade cool off to -150 °C. A simple solution is to spin your craft along its axis to ensure an even heat load on all sides, similar to the way you rotate sausages on your barbecue.

But one of the most challenging problems facing electronics in space is radiation. [Sergiy] explains in detail the various types of radiation that a spacecraft might encounter: charged particles in the Van Allen belts, cosmic rays once you get away from Low Earth orbit, and a variety of ionized junk ejected from the Sun every now and then. The easiest way to reduce the radiation load on your electronics is simply to stay near Earth and take cover within its magnetic field.

For interplanetary spacecraft there’s no escaping the onslaught, and the only to survive is to make your electronics “rad-hard”. Shielding is generally not an option because of weight constraints, so engineers make use of components that have been tested in radiation chambers to ensure they will not suddenly short-circuit. Adding redundant circuits as well as self-monitoring features like watchdog timers also helps to make flight computers more robust.

[Sergiy]’s talk is full of interesting anecdotes that will delight the inner astronaut in all of us. Ever imagined a bat trying to hitch a ride on a Space Shuttle? As it turns out, one aspiring space bat did just that. And while designing space-qualified electronics is not something most of us do every day, [Sergiy]’s experiences provide plenty of tips for more down-to-earth problems. After all, salt and moisture will eat away cables on your bicycle just as they do on a moon rocket.

Be sure to also check out the links embedded in the talk’s slides for lots of great background information.

Continue reading “Remoticon 2021 // Sergiy Nesterenko Keeps Hardware Running Through Lightning And Cosmic Rays” →

Keebin’ With Kristina: The One With The Ballpoint Typewriters

February 10, 2022 by Kristina Panos 7 Comments

So you want to minimize finger movement when you type, but don’t have three grand to drop on an old DataHand, or enough time to build the open-source lalboard? Check out these two concept keebs from [SouthPawEngineer], which only look like chord boards.

Every key on the home row is a five-way switch — like a D-pad with straight down input. [SouthPawEngineer] has them set up so that each one covers a QWERTY column. So like, for the left pinky switch, up is Q, right is A, down is Z, and left is 1. Technically, the split has 58 keys, and the uni has 56.

Both of these keebs use KB2040 boards, which are Adafruit’s answer to the keyboard-building craze of these roaring 2020s. These little boards are of course easy to program with CircuitPython, which supports KMK, an offshoot of the popular QMK. Thanks for the tip, [foamyguy]!

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Mining And Refining: Lithium, Powering The Future With Brine

February 9, 2022 by Dan Maloney 28 Comments

Many years ago, I read an article about the new hotness: lithium batteries. The author opened with what he no doubt thought was a clever pop culture reference by saying that the mere mention of lithium would “strike fear in the hearts of Klingons.” It was a weak reference to the fictional “dilithium crystals” of Star Trek fame, and even then I found it a bit cheesy, but I guess he had to lead with something.

Decades later, a deeper understanding of the lore makes it clear that a Klingon’s only fear is death with dishonor, but there is a species here on earth that lives in dread of lithium: CEOs of electric vehicle manufacturing concerns. For them, it’s not the presence of lithium that strikes fear, but the relative absence of it; while it’s the 25th most abundant element in the Earth’s crust, and gigatons are dissolved into the oceans of the world, lithium is very reactive and thus tends to be diffuse, making it difficult to obtain concentrated in the quantities their businesses depend on.

As the electric vehicle and renewable energy markets continue to grow, the need for lithium to manufacture batteries will grow with it, potentially to the point where demand outstrips the mining industry’s production capability. To understand how that imbalance may be possible, we’ll take a look at how lithium is currently mined, as well as examine some new mining techniques that may help fill the coming lithium gap.

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