Hackaday Columns

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This excellent content from the Hackaday writing crew highlights recurring topics and popular series like Linux-Fu, 3D-Printering, Hackaday Links, This Week in Security, Inputs of Interest, Profiles in Science, Retrotechtacular, Ask Hackaday, Teardowns, Reviews, and many more.

This Week In Security: Geopolitical Hacktivism, Antivirus Mining, And Linux Malware

January 28, 2022 by 15 Comments

The CIA Hacktivists have launched a sort of ransomware campaign against the Belarusian rail system, but instead of cryptocurrency, they want the release of political prisoners and removal of Russian soldiers. This could be called an example of cyber-terrorism, though there is a reasonable theory that this is a state-sponsored hack, masquerading as hacktivism. What does seem certain is that something has interrupted rail transit, and a group on Twitter has produced convincing proof of a breach.

Your Antivirus Now Includes a CryptoMiner

Don’t look now, but your latest update of Norton 360 or Avira may have installed a cryptocurrency mining module. The silver lining is that some sanity has been retained, and you have to opt-in to the crypto scheme before your machine starts spending its spare cycles on mining. For users who do, they’re put into a mining pool, making for small payouts for most hardware. Norton, naturally, takes a 15% fee off the top for their trouble.

The State of Linux Malware

There used to be an adage that Linux machines don’t get malware. That’s never really been quite true, but the continued conquest of the server landscape has had the side effect of making Linux malware an even greater danger. Crowdstrike has seen a 35% increase in Linux malware in 2021, with three distinct categories leading the charge: XorDDoS, Mozi, and Mirai. Continue reading “This Week In Security: Geopolitical Hacktivism, Antivirus Mining, And Linux Malware” →

Remoticon 2021 // Voja Antonic Makes You A Digital Designer

January 27, 2022 by 10 Comments

[Voja Antonic] has been building digital computers since before many of us were born. He designed with the Z80 when it was new, and has decades of freelance embedded experience, so when he takes the time to present a talk for us, it’s worth paying attention.

For his Remoticon 2022 presentation, he will attempt to teach us how to become a hardware expert in under forty minutes. Well, mostly the digital stuff, but that’s enough for one session if you ask us. [Voja] takes us from the very basics of logic gates, through combinatorial circuits, sequential circuits, finally culminating in the description of a general-purpose microprocessor.

A 4-bit ripple-carry adder with additional CPU flag outputs

As he demonstrates, complex digital electronics systems really are just built up in a series of steps of increasing complexity. starting with individual active elements (transistors operating as switches) forming logic elements capable of performing simple operations.

From there, higher level functions such as adders can be formed, and from those an ALU and so on. Conceptually, memory elements can be formed from logic gates, but it’s not the most efficient way to do it, and those tend to be made with a smaller and faster circuit. But anyway, that model is fine for descriptive purposes.

Once you have combinatorial logic circuits and memory elements, you have all you need to make the necessary decoders, sequencers and memory circuits to build processors and other kinds of higher complexity circuits.

Obviously forty minutes isn’t anywhere nearly enough time time to learn all of the intricacies of building a real microprocessor like the pesky details of interfacing with it and programming it, but for getting up the learning curve from just a knowledge of binary numbers to an understanding of how a CPU is built, it’s a pretty good starting point.

Now, If you can only tear your eyes away from his slick game-of-life wall mounted LED display, you might pick up a thing or two.

Continue reading “Remoticon 2021 // Voja Antonic Makes You A Digital Designer” →

Linux Fu: Bash Strings

January 26, 2022 by 40 Comments

If you are a traditional programmer, using bash for scripting may seem limiting sometimes, but for certain tasks, bash can be very productive. It turns out, some of the limits of bash are really limits of older shells and people code to that to be compatible. Still other perceived issues are because some of the advanced functions in bash are arcane or confusing.

Strings are a good example. You don’t think of bash as a string manipulation language, but it has many powerful ways to handle strings. In fact, it may have too many ways, since the functionality winds up in more than one place. Of course, you can also call out to programs, and sometimes it is just easier to make a call to an awk or Python script to do the heavy lifting.

But let’s stick with bash-isms for handling strings. Obviously, you can put a string in an environment variable and pull it back out. I am going to assume you know how string interpolation and quoting works. In other words, this should make sense:

echo "Your path is $PATH and the current directory is ${PWD}"

The Long and the Short

Suppose you want to know the length of a string. That’s a pretty basic string operation. In bash, you can write ${#var} to find the length of $var:


#/bin/bash
echo -n "Project Name? "
read PNAME
if (( ${#PNAME} > 16 ))
then
   echo Error: Project name longer than 16 characters
else
   echo ${PNAME} it is!
fi

Continue reading “Linux Fu: Bash Strings” →

An snowy city street.

The Road Is Peppered With Rock Salt Alternatives

January 25, 2022 by 79 Comments

Every winter, millions of tons of rock salt is sprinkled across roads in the US, mostly in the Midwest and Northeast regions. It’s a cheap and effective way to prevent accidents. Rock salt is chemically the same as the stuff that sits next to the pepper, except it isn’t as finely ground, and it doesn’t have sodium or potassium iodine added to it to prevent goiters. Both table salt and rock salt melt ice by lowering the freezing point of water. So does sugar.

Much of what we salt the Earth with every winter comes from underground networks of salt crystal that formed when various ancient seas dried up. As natural as it may be, rock salt is bad for the environment. For one thing, chloride is forever, and can’t easily be decoupled from the soil and water it taints when it washes away. Rock salt also corrodes concrete, makes its way into the groundwater, and is bad for pets. Worst of all, its efficacy drops along with the temperature. At 15° F (-9° C), rock salt loses more than 86% of its melting power.

Disposable Detroit

All this salt is not great for cars, either — it’s bad for the paint and eats up the frame. In the saltiest parts of the US, aka The Salt Belt, cars only last a handful of years before they become Flintstones mobiles. Well, not really, but salt is terrible for the brake lines and most of the undercarriage. Consumer woes aside, there’s a real environmental impact to manufacturing all these disposable cars to meet the demand.

But the problem is that we need to use salt, or at something like it. Even though millions of people are staying home a whole lot more, the trucking industry still relies on salted highways and local roads. So if you like stocked grocery stores and stuff arriving from the Bezos Barn in a timely fashion, you can see the problem. So what are the alternatives? Are there any?

Continue reading “The Road Is Peppered With Rock Salt Alternatives” →

Can Robots Give Good Hugs?

January 24, 2022 by 29 Comments

We could all use a hug once in a while. Most people would probably say the shared warmth is nice, and the squishiness of another living, breathing meatbag is pretty comforting. Hugs even have health benefits.

But maybe you’re new in town and don’t know anyone yet, or you’ve outlived all your friends and family. Or maybe you just don’t look like the kind of person who goes for hugs, and therefore you don’t get enough embraces. Nearly everyone needs and want hugs, whether they’re great, good, or just average.

So what makes a good hug, anyway? It’s a bit like a handshake. It should be warm and dry, with a firmness appropriate to the situation. Ideally, you’re both done at the same time and things don’t get awkward. Could a robot possibly check all of these boxes? That’s the idea behind HuggieBot, the haphazardly humanoid invention of Katherine J. Kuchenbecker and team at the Max Planck Institute for Intelligent Systems in Stuttgart, Germany (translated). User feedback helped the team get their arms around the problem.

Continue reading “Can Robots Give Good Hugs?” →

Bendy Straws

Compliant Mechanisms Hack Chat

January 24, 2022 by 5 Comments

Join us on Wednesday, January 26 at noon Pacific for the Compliant Mechanisms Hack Chat with Amy Qian!

When it comes to putting together complex mechanisms, we tend to think in a traditional design language that includes elements like bearings, bushings, axles, pulleys — anything that makes it possible for separate rigid bodies to move against each other. That works fine in a lot of cases — our cars wouldn’t get very far without such elements — but there are simpler ways to transmit force and motion, like compliant mechanisms.

Compliant mechanisms show up in countless products, from the living hinge on a cheap plastic box to the nanoscale linkages etched into silicon inside a MEMS accelerometer. They reduce complexity by putting the elasticity of materials to work and by reducing the number of parts it takes to create an assembly. And they can help make your projects easier and cheaper to build — if you know the secrets of their design.

join-hack-chatAmy Qian, from the Amy Makes Stuff channel on YouTube,  is a mechanical engineer with an interest in compliant mechanisms, so much so that she ran a workshop about them at the 2019 Superconference. She’ll stop by the Hack Chat to share some of what she’s learned about compliant mechanisms, and to help us all build a little flexibility into our designs.

Our Hack Chats are live community events in the Hackaday.io Hack Chat group messaging. This week we’ll be sitting down on Wednesday, January 26 at 12:00 PM Pacific time. If time zones have you tied up, we have a handy time zone converter.

 

Continue reading “Compliant Mechanisms Hack Chat” →

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Hackaday Links: January 23, 2022

January 23, 2022 by 14 Comments

When Tonga’s Hunga-Tonga Hunga-Ha’apai volcano erupted on January 15, one hacker in the UK knew just what to do. Sandy Macdonald from York quickly cobbled together a Raspberry Pi and a pressure/humidity sensor board and added a little code to create a recording barometer. The idea was to see if the shock wave from the eruption would be detectable over 16,000 km away — and surprise, surprise, it was! It took more than 14 hours to reach Sandy’s impromptu recording station, but the data clearly show a rapid pulse of increasing pressure as the shockwave approached, and a decreased pressure as it passed. What’s more, the shock wave that traveled the “other way” around the planet was detectable too, about seven hours after the first event. In fact, data gathered through the 19th clearly show three full passes of the shockwaves. We just find this fascinating, and applaud Sandy for the presence of mind to throw this together when news of the eruption came out.

Good news for professional astronomers and others with eyes turned skyward — it seems like the ever-expanding Starlink satellite constellation isn’t going to kill ground-based observation. At least that’s the conclusion of a team using the Zwicky Transient Facility (ZTF) at the Palomar Observatory outside San Diego. ZTF is designed to catalog anything that blinks, flashes, or explodes in the night sky, making it perfect to detect the streaks from the 1,800-odd Starlink satellites currently in orbit. They analyzed the number of satellite transients captured in ZTF images, and found that fully 20 percent of images show streaks now, as opposed to 0.5 percent back in 2019 when the constellation was much smaller. They conclude that at the 10,000 satellite full build-out, essentially every ZTF image will have a streak in it, but since the artifacts are tiny and well-characterized, they really won’t hinder the science to any appreciable degree.

Speaking of space, we finally have a bit of insight into the causes of space anemia. The 10% to 12% decrease in red blood cells in astronauts during their first ten days in space has been well known since the dawn of the Space Age, but the causes had never really been clear. It was assumed that the anemia was a result of the shifting of fluids in microgravity, but nobody really knew for sure until doing a six-month study on fourteen ISS astronauts. They used exhaled carbon monoxide as a proxy for the destruction of red blood cells (RBCs) — one molecule of CO is liberated for each hemoglobin molecule that’s destroyed — and found that the destruction of RBCs is a primary effect of being in space. Luckily, there appears to be a limit to how many RBCs are lost in space, so the astronauts didn’t suffer from complications of severe anemia while in space. Once they came back to gravity, the anemia reversed, albeit slowly and with up to a year of measurable changes to their blood.

From the “Better Late Than Never” department, we see that this week that Wired finally featured Hackaday Superfriend Sam Zeloof and his homemade integrated circuits. We’re glad to see Sam get coverage — the story was also picked up by Ars Technica — but it’s clear that nobody at either outfit reads Hackaday, since we’ve been featuring Sam since we first heard about his garage fab in 2017. That was back when Sam was still “just” making transistors; since then, we’ve featured some of his lab upgrades, watched him delve into electron beam lithography, and broke the story on his first legit integrated circuit. Along the way, we managed to coax him out to Supercon in 2019 where he gave both a talk and an interview.

And finally, if you’re in the mood for a contest, why not check out WIZNet’s Ethernet HAT contest? The idea is to explore what a Raspberry Pi Pico with Ethernet attached is good for. WIZNet has two flavors of board: one is an Ethernet HAT for the Pico, while the other is as RP2040 with built-in Ethernet. The good news is, if you submit an idea, they’ll send you a board for free. We love it when someone from the Hackaday community wins a contest, so if you enter, be sure to let us know. And hurry — submissions close January 31.