Hackaday Podcast 062: Tripping Batteries, Ventilator Design, Stinky Prints, And Simon Says Servos

April 10, 2020 by Mike Szczys No comments

Hackaday editors Elliot Williams and Mike Szczys check out the week’s awesome hacks. From the mundane of RC controlled TP to a comprehensive look into JTAG for Hackers, there’s something for everyone. We discuss a great guide on the smelly business of resin printing, and look at the misuse of lithium battery protection circuits. There’s a trainable servo, star-tracking space probes, and a deep dive into why bootstrapped ventilator designs are hard.

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!

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 (60 MB or so.)

Continue reading “Hackaday Podcast 062: Tripping Batteries, Ventilator Design, Stinky Prints, And Simon Says Servos” →

This Week In Security: Zoom (Really This Time), Fingerprints, And Bloatware

April 10, 2020 by Jonathan Bennett 9 Comments

You were promised Zoom news last week, but due to a late night of writing, that story was delayed to this week. So what’s the deal with Zoom? Google, SpaceX, and even the government of Taiwan and the US Senate have banned Zoom. You may remember our coverage of Zoom from nearly a year ago, when Apple forcibly removed the Zoom service from countless machines. The realities of COVID-19 have brought about an explosion of popularity for Zoom, but also a renewed critical eye on the platform’s security.

“Zoombombing”, joining a Zoom meeting uninvited, made national headlines as a result of a few high profile incidents. The US DOJ even released a statement about it. Those incidents seem to have been a result of Zoom default settings: no meeting passwords, no “waiting room”, and meeting IDs that persist indefinitely. A troll could simply search google for Zoom links, and try connecting to them until finding an active meeting. Ars ran a great article on how to avoid getting zoombombed (thanks to Sheldon for pointing this out last week).

There is another wrinkle to the Zoom story. Zoom is technically an American company, but its Chinese roots put it in a precarious situation. Recently it’s been reported that encryption keying is routed through infrastructure in China, even though the calling parties are elsewhere. In some cases, call data itself goes through Chinese infrastructure, though that was labeled as a temporary bug. Zoom was also advertising its meetings as having end-to-end encryption. That claim was investigated, and discovered to be false. All meetings get decrypted at Zoom servers, and could theoretically be viewed by Zoom staff. Continue reading “This Week In Security: Zoom (Really This Time), Fingerprints, And Bloatware” →

No Windshield? No Problem, Says McLaren

April 9, 2020 by Kristina Panos 79 Comments

All the best sports cars look like they’re moving when they’re just sitting there, and the lines on McLaren’s newest limited-edition plaything redefine that look of speed standing still. Maybe it’s the sneering headlights or the streamlined, reverse-1966 Batmobile styling. Whatever it is, the 804-horsepower two-seater project Elva looks like it’s leaping off the line into the future.

But this future is free from the last thing we’d expect to see removed from any vehicle, especially a $1.7 million supercar — the windshield. Now that the headphone jack has been deemed expendable, it seems that nothing is sacred. The Elva is already a permanent convertible with no windows.

Though McLaren didn’t start this weird and windowless fire, the Elva is meant to fan the flames of futurism. She joins the ranks of a few windshield-free models from Ferrari, Mercedes-Benz, and Aston Martin. In the other guy’s cars, you’ll need a helmet above 30MPH unless you love the thunderous sounds of air buffeting and blown-out hair. It’s a young idea with a few bugs to work out.

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What Does A Dependable Open Source Ventilator Look Like?

April 9, 2020 by Mike Szczys 61 Comments

Ventilators are key in the treating the most dire cases of coronavirus. The exponential growth of infections, and the number of patients in respiratory distress, has outpaced the number of available ventilators. In times of crisis, everyone looks for ways they can help, and one of the ways the hardware community has responded is in work toward a ventilator design that can be rapidly manufactured to meet the need.

The difficult truth is that the complexity of ventilator features needed to treat the sickest patients makes a bootstrapped design incredibly difficult, and I believe impossible to achieve in quantity on this timeline. Still, a well-engineered and clinically approved open source ventilator might deliver many benefits beyond the current crisis. Let’s take a look at some of the efforts we’ve been seeing recently and what it would take to pull together a complete design.

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The Real Lessons About 3D Printed Face Shields: Effective Engineering Response In Times Of Crisis

April 8, 2020 by Donald Papp 83 Comments

3D printed face shields and other health equipment is big news right now. Not long ago, Prusa Research rapidly designed and manufactured 3D printed face shields and donated them to the Czech Ministry of Health. Their effort is ongoing, and 3D printers cranking out health equipment like the NIH approved design has been peppering headlines ever since.

The Important Part Isn’t 3D Printers

The implied takeaway from all the coverage is that 3D printers are a solution to critical equipment shortages, but the fact that 3D printers are involved isn’t really the important part. We all know printers can make plastic parts, so what should be the real takeaway? The biggest lessons we can learn about Prusa’s ongoing effort are related to how they’ve gone about it.

Continue reading “The Real Lessons About 3D Printed Face Shields: Effective Engineering Response In Times Of Crisis” →

Linux Fu: Tracing System Calls

April 7, 2020 by Al Williams 11 Comments

One of the nice things about Linux and similar operating systems is that you can investigate something to any level you wish. If a program has a problem you can decompile it, debug it, trace it, and — if necessary — even dig into the source code for the kernel and most of the libraries the program is probably using. However, the tools to do this aren’t ones you use every day. One very interesting tool is strace. Using it you can see what system calls any program makes and that can sometimes give you important clues about how the program works or, probably more often, why it doesn’t work.

Let’s consider the least complex use of the command. Suppose you want to make symlink from testxmit.grc to the /tmp directory. That command is simple:

ln -sf testxmit.grc /tmp

But if you tell strace to run it, the command becomes:

strace ln -sf testxmit.grc /tmp

You might want to redirect the output to a file using the shell or the -o option, though. Some commands generate a lot and often the first page or two of output isn’t really what you care about anyway. Continue reading “Linux Fu: Tracing System Calls” →

3D Printering: When Resin Printing Gets Smelly

April 7, 2020 by Donald Papp 20 Comments

Nowadays, resin printers are highly accessible and can do some great stuff. But between isopropyl alcohol for part rinsing and the fact that some resins have a definite smell to them, ventilation can get important fast. The manufacturers don’t talk much about this part of the resin printing experience, but it’s there nevertheless. So what can be done when smells become a problem?

I recently had to deal with this when I printed several liters of resin worth of parts. That’s a lot of resin, and a lot of alcohol for part washing. Smells — which had never been much of a problem in my work area — suddenly became an issue.