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Hackaday Links: April 18, 2021

More bad news from Mars this week, and this time not just from Perseverance. Last week the eagerly anticipated first flight of the helicopter Ingenuity was delayed for a couple of days after failing a full-speed spin-up test of its rotors. That appears to have been a bigger deal than initially thought, as it required a significant rewrite of the helicopter’s software. That meant testing, of course, and subsequent upload to the UAV, which at 174 million miles away takes a bit of doing. The good news is that they were able to complete the full-speed rotor test without the full program upload, so we’re one step closer to flight, which may take place as early as Monday morning.

Meanwhile, over at Elysium Planitia, the Mars InSight lander has troubles of its own. The geophysical laboratory, which has been trying to explore the inner structure of Mars since landing in 2018, entered an “emergency hibernation” state this week because of a lack of sufficient power generation. Unlike the radioisotope-powered Perseverance rover, InSight relies on a pair of solar panels for its electricity, and those panels are being obscured by Martian dust. The panels normally get blown clean by Martian winds, but things have been calm lately and the dust has really built up. If this seems like deja vu all over again, it’s probably because a planet-wide dust storm is what killed the plucky Opportunity rover back in 2018. Here’s hoping the wind picks up a little and InSight can get back to work.

Funny what crops up in one’s newsfeed, especially when one is responsible for putting out content that populates others’ newsfeeds. We recently took a look at the dangers of “zinc fever”, a flu-like illness that can crop up after inhaling gasses produced by molten zinc. That resulted in stumbling across an article from last year about mild steel welding fumes being classified as a human carcinogen. This comes from the Health and Safety Executive, a UK government agency concerned with workplace health issues. The release is an interesting read, and it suggests that mild steel fumes can cause not only lung cancer but kidney cancer. The announcement is mainly concerned with British workplaces, of course, but there are some interesting tidbits in there, such as the fact that welding fumes make dust particles so small that they can reach down into the very lowest reaches of lungs, the alveoli where gas exchange occurs. It’s enough to make one invest in PAPR or some kind of fume extractor.

For those of a certain vintage, our first computer was probably something that bore little resemblance to a PC or laptop. It was likely a single-board affair or something like a C64, and acquiring the essential bit of hardware usually left little in the budget for a proper monitor. Little 12″ B&W TVs were a dime a dozen, though, and easily — if grainily — enlisted into service as a monitor by way of an RF modulator. To recreate a little of that magic with modern hardware, Hackaday contributor Adam Zeloof came up with the PiMod Zero, an RF-modulator hat for the Raspberry Pi Zero that turns the component video into an NTSC analog signal. He’s open-sourced the design files, or there’s a CrowdSupply campaign for those who prefer to buy.

And finally, if you somehow traveled back in time to the 1940s with a laptop, how long would it have taken you to crack the Enigma code? Longer than you think, at least according to Dr. Mike Pound over at Computerphile, who released a fascinating video on how Enigma worked and what it took for Turing and the gang at Bletchley to crack the code. We knew some of the details of Enigma’s workings before seeing this video, but Mike’s explanation was really good. And, his explanation of the shortcut method he used to decode an Enigma message made the whole process clearer to us than it’s ever been. Interesting stuff.

Continue reading “Hackaday Links: April 18, 2021”

Sit Up Straight!: Open Source Bluetooth Posture Sensing

As more and more people spend their working hours behind a computer, bad posture and the accompanying back pain and back problems become a growing epidemic. To combat this in his own daily life, [ImageryEel] made PosturePack, a wearable Bluetooth-enabled posture sensor.

The PosturePack is designed to fit into a small pocket sewn into the pack of an undershirt, between the shoulder blades. It consists of a custom PCB with an ATmega32U4, BNO055 IMU, Bluetooth module,  small LiPo and power circuitry. Based on the orientation data from the IMU, a notification is sent over Bluetooth to a smartphone whenever the user hunches forward.

[ImageryEel] says although the mobile notifications worked, haptic feedback integrated into the unit would be a better option. This could also be used to remind the user to stand up and take a break now and then, and provide an alternative to a smartwatch for activity monitoring without sending every movement to someone else’s servers. Software will always be the hardest part for projects like these, especially as the device become “smarter”. Learning to recognize activity and postures is actually a good place for tiny machine learning models.

Compared The posture sensors we covered before had to be installed and set up at a specific workstation, like an ultrasound-based version attached to a chair, and a webcam-based version.

Surviving The Pandemic As A Hacker: Take Care Of Your Mental Health

As we’ve looked at the subject of face masks in the first two parts of this series, our emphasis has been on a physical step to aid your chances of making it through the COVID-19 pandemic in one piece. But given that the upheaval caused by all the social changes enacted to protect the population are likely to leave an indelible mark on those who live through them, there are significant aspects of surviving all this that go beyond the physical.

This will be a once-in-a-lifetime event for many people, a significant number will find it traumatic in some way, and for many of those people there will be an immediate and then ongoing effect on mental health. If anyone is in doubt as to from what position this is coming, I count myself among that number.

The Pressure Of A Once In A Lifetime Event

Piccadilly Circus, London, during the COVID-19 lockdown. Normally this is packed.
Piccadilly Circus, London, during the COVID-19 lockdown. Normally this is packed. Kwh1050 / CC BY-SA 4.0

Different countries have placed their own public health restrictions on their populations, but it’s likely that many of you are in some form of lockdown situation, with social or communal  activities and locations closed or curtailed, going out restricted, and with all around you in the same situation. A perfect storm of having social outlets removed while simultaneously being stuck at home perhaps with family or housemates you’d prefer not to spend too much time with is not ideal. Add to that the multiple stresses from the pandemic itself as well as other news stories from our turbulent world, and it’s hardly a surprising that it’s taking a toll. Continue reading “Surviving The Pandemic As A Hacker: Take Care Of Your Mental Health”

PPE Testing Hack Chat

Join us on Wednesday, June 17 at noon Pacific for the PPE Testing Hack Chat with Hiram Gay and Lex Kravitz!

When the COVID-19 pandemic unfolded in early 2020, the hacker community responded in the most natural way possible: by making stuff. Isolation and idleness lead to a creative surge as hackers got to work on not only long-deferred fun projects but also potential solutions to problems raised by an overloaded medical system and choked supply chains. And so workshops and hackerspaces the world over churned out everything from novel ventilators to social-distancing aids.

But perhaps the greatest amount of creative energy was set loose on the problem of personal protective equipment, or PPE. This was due in no small part to predictions of a severe shortage of the masks, gowns, and gloves that front-line medical workers would need to keep them safe while caring for pandemic victims, but perhaps also because, at least compared to the complexity of something like a ventilator, building a mask seems easy. And indeed it is as long as you leave unanswered the crucial question: does the thing work?

Answering that question is not as easy as it seems, though. It’s not enough to assume that putting some filtration between the user and the world will work; you’ve got to actually make measurements. Hiram Gay and Lex Kravitz, colleagues at the Washington University School of Medicine in St. Louis, actually crunched the numbers on the full-face snorkel mask they modified for use as a face shield for medical PPE, and they have a lot of insights to share about proper testing of such devices. They’ll join the Hack Chat this week to discuss their findings, offer advice to builders, and reveal how they came up with their idea for a different way to build and test PPE.

join-hack-chatOur Hack Chats are live community events in the Hackaday.io Hack Chat group messaging. This week we’ll be sitting down on Wednesday, June 17 at 12:00 PM Pacific time. If time zones have you down, we have a handy time zone converter.

Click that speech bubble to the right, and you’ll be taken directly to the Hack Chat group on Hackaday.io. You don’t have to wait until Wednesday; join whenever you want and you can see what the community is talking about.
Continue reading “PPE Testing Hack Chat”

Rapid Prototyping Hack Chat

Join us on Wednesday, June 10 at noon Pacific for the Rapid Prototyping Hack Chat with Erika Earl!

When one thinks of the Jet Propulsion Lab, the NASA lab responsible for such amazing feats of engineering as Mars rovers and galaxy-exploring spacecraft like Voyager, one does not necessarily think of it as a hotbed of medical innovation. But when the COVID-19 pandemic started its march around the globe, JPL engineers decided to turn their skills from exploring other worlds to helping keep people alive in this one. Fittingly, the challenge they tackled was perhaps the most technically challenging: to build a ventilator that’s simple enough to be built in large numbers, enough to make a difference to the predicted shortfall, but that does the non-trivial job of keeping people breathing as safely as possible.

The result was VITAL, or Ventilator Intervention Technology Accessible Locally. It was designed, prototyped, and tested on an incredibly ambitious timetable: 37 days total. That number alone would be shocking enough, but when one adds in the disruptions and disconnection forced on the team of JPL engineers by the sudden need to self-isolate and work remotely that came up in the middle of the design process, it’s a wonder the team was able to get anywhere. But they worked through the technical and managerial issues and delivered a design that has now been licensed out to eight manufacturers under a no-fee license.

What does it take to bring something as complex as a ventilator to market in so short a time? To delve into that question, Supply Frame’s Erika Earl, who was part of the VITAL team, will stop by the Hack Chat. We’ll talk to her about being on the JPL team, what the design and prototyping process was like, and how the lessons learned here can apply to any team-based rapid-prototyping effort. You may not be building a ventilator in 37 days, but chances are good you can learn something useful from those who did.

join-hack-chatOur Hack Chats are live community events in the Hackaday.io Hack Chat group messaging. This week we’ll be sitting down on Wednesday, June 10 at 12:00 PM Pacific time. If time zones have you down, we have a handy time zone converter.

Click that speech bubble to the right, and you’ll be taken directly to the Hack Chat group on Hackaday.io. You don’t have to wait until Wednesday; join whenever you want and you can see what the community is talking about.
Continue reading “Rapid Prototyping Hack Chat”

Google And Apple Reveal Their Coronavirus Contact Tracing Plans: We Kick The Tires

Google and Apple have joined forces to issue a common API that will run on their mobile phone operating systems, enabling applications to track people who you come “into contact” with in order to slow the spread of the COVID-19 pandemic. It’s an extremely tall order to do so in a way that is voluntary, respects personal privacy as much as possible, doesn’t rely on potentially vulnerable centralized services, and doesn’t produce so many false positives that the results are either ignored or create a mass panic. And perhaps much more importantly, it’s got to work.

Slowing the Spread

As I write this, the COVID-19 pandemic seems to be just turning the corner from uncontrolled exponential growth to something that’s potentially more manageable, but it’s not clear that we yet see an end in sight. So far, this has required hundreds of millions of people to go into essentially voluntary quarantine. But that’s a blunt tool. In an ideal world, you could stop the disease globally in a couple weeks if you could somehow test everyone and isolate those who have been exposed to the virus. In the real world, truly comprehensive testing is impossible, and figuring out whom to isolate is extraordinarily difficult due to two factors: COVID-19 has a long incubation period during which it is nonetheless transmissible, and some or even most people don’t know they have it. How can you stop what you can’t see, and even when you can detect it, it’s a week too late?

One promising approach is to isolate those people who’ve been in contact with known cases during the stealth contagion period. To do this is essentially to keep a diary of everyone you’ve been in contact with for the last week or two, and then if you eventually test positive for COVID-19, alert them all so that they can keep from infecting others even before they test positive: track and trace. Doctors can do this by interviewing patients who test positive (this is the “contact tracing” we’ve been hearing so much about), but memory is imperfect. Enter a technological solution. Continue reading “Google And Apple Reveal Their Coronavirus Contact Tracing Plans: We Kick The Tires”

Homemade Masks In A Time Of Shortage

Due to the worldwide pandemic of COVID-19, there has been a huge shortage of N95 masks. [] from Smart Air has been working on designs for a DIY mask that may be able to protect those who haven’t been able to secure their own masks. While there may be an abundance of memes around the various material people have been able to use to substitute for the filters, there is some very real science behind the sorts of materials that can effectively protect us from the virus.

According to a studied performed at Cambridge University during the 2009 H1N1 flu pandemic, while surgical masks perform the best at capturing Bacillus atrophaeus bacteria (0.93-1.25 microns) and Bacteriophage MS virus (0.023 microns), vacuum cleaner bags, and tea towels, and cotton T-shirts were not too far behind. The coronavirus is 0.1-0.2 microns, well within the range for the results of the tests.

As it turns out, cotton homemade masks may be quite effective as alternatives – not to mention reusable. They also found out that double layering the masks didn’t help with improving the protection against viruses. On the other hand, one significant design choice was the breathability of the material. While vacuum cleaner bags may be quite effective at keeping out small particles, they aren’t as comfortable or easy to breathe in as cotton masks.

Have you tried making your own cotton masks? In a time when hospitals are running low on surgical masks, it’s possibly the best option for helping to keep much-needed medical supplies in the hands of those helping at the front line.

[Thanks to pie for the tip!]