Thunder Pack Is A Bolt Of Lightning For Wearables

March 25, 2020 by Kristina Panos 19 Comments

Do you need portable power that packs a punch? Sure you do, especially if you want to light up the night by mummifying yourself with a ton of LED strips. You aren’t limited to that, of course, but it’s what we pictured when we read about [Jeremy]’s Thunder Pack. With four PWM channels at 2.3 A each, why not go nuts? [Jeremy] has already proven the Thunder Pack out by putting it through its paces all week at Burning Man.

After a few iterations, [Jeremy] has landed on the STM32 microcontroller family and is currently working to upgrade to one with enough flash memory to run CircuitPython.

The original version was designed to run on a single 18650 cell, but [Jeremy] now has three boards that support similar but smaller rechargeable cells for projects that don’t need quite as much power.

We love how small and powerful this is, and the dongle hole is a great touch because it opens up options for building it into a wearable. [Jeremy] made a fantastic pinout diagram and has a ton of code examples in the repo. If you want to wade into the waters of wearables, let whimsical wearables wizard [Angela Sheehan] walk you through the waves.

Ventilators 101: What They Do And How They Work

March 25, 2020 by Bob Baddeley 88 Comments

Treating the most serious cases of COVID-19 calls for the use of ventilators. We’ve all heard this, and also that there is a shortage of these devices. But there is not one single type of ventilator, and that type of machine is not the only option when it comes to assisted breathing being used in treatment. Information is power and having better grasp on this topic will help us all better understand the situation.

We recently wrote about a Facebook group focused on open source ventilators and other technology that could assist in the COVID-19 pandemic. There was an outpouring of support, and while the community is great when it comes to building things, it’s clear we all need more information about the problems doctors are currently dealing with, and how existing equipment was designed to address them.

It’s a long and complicated topic, though, so go get what’s left of your quarantine snacks and let’s dig in.

Continue reading “Ventilators 101: What They Do And How They Work” →

Ken Shirriff Unfolds A Nuclear Missile Guidance Computer With Impressive Memory

March 25, 2020 by Mike Szczys 13 Comments

Longtime followers of [Ken Shirriff’s] work are accustomed to say asking “Where does he get such wonderful toys?”. This time around he’s laid bare the guidance computer from a Titan missile. To be specific, this is the computer that would have been found in the Titan II, an intercontinental ballistic missile that you may remember as a key part of the plot of the classic film WarGames. Yeah, those siloed nukes.

Amazingly these computers were composed of all digital logic, no centralized controller chip in this baby. That explains the need for the seven circuit boards which host a legion of logic chips, all slotting into a backplane.

But it’s not the logic that’s mind-blowing, it’s the memory. Those dark rectangles on almost every board in the image at the top of the article are impressively-dense patches of magnetic core memory. That fanout is one of two core memory modules that are found in this computer. With twelve plates per module (each hosting two bits) plus a parity bit on an additional plate, words were composed of 25-bits and the computer’s two memory modules could store a total of 16k words.

This is 1970’s tech and it’s incredible to think that when connected to the accelerometers and gyros that made up the IMU this could use dead reckoning to travel to the other side of the globe. As always, [Ken] has done an incredible job of walking through all parts of the hardware during his teardown. He even includes the contextual elements of his analysis by sharing details of this moment in history near the end of his article.

If you want to geek out a little bit more about memory storage of yore, you can get a handle on core, drum, delay lines, and more in Al Williams’ primer.

Hack The Quarantine, Not Just The Medical Equipment

March 25, 2020 by Jenny List 10 Comments

As the COVID-19 pandemic invades in some way every corner of life, we’ve seen significant effort from the hardware community in considering the problem of inadequate supplies of medical equipment. The pandemic and its associated quarantine and lockdowns do not stop at medical supplies though, a whole host of problems associated with the whole population self-isolating are there to be solved. This makes Hack Quarantine, an online event that bills itself as “A global virtual hackathon”, particularly interesting. It’s encouraging its participants to look at the wider aspects of the whole thing rather than solely dreaming up an open-source ventilator design, because in the absence of clinical trials or indeed any experts in medical devices it’s possible that medical equipment from a hackathon might be of limited usability.

The hackathon will run from March 23rd to April 12th, and it already has a schedule of talks and workshops. We can’t help noticing a dearth of hardware-related stuff among all the software, and perhaps this could be where you come in. It’s something that never ceases to amaze us as Hackaday writers, the depth of hardware skill among our readership, and we’re guessing that plenty of you could bring something to this event.

We’ve brought you more than a few COVID-19 stories over the last few weeks. If this hackathon isn’t for you then can we point you at our Folding@Home team? Also, you may wish to look at the best fabric choice for your own face masks.