If you have worn a mask and glasses together for more than a quarter of a second, you are probably annoyed that we don’t have a magical solution for foggy lenses. Moisture-laden air is also a good indicator of where unfiltered air is escaping. Most masks have some flexible metal across the nose bridge that is supposed to seal the top, but it is woefully inadequate. The Badger Seal by [David Rothamer] and [Scott Sanders] from the University of Wisconsin-Madison College of Engineering is free to copy during the COVID-19 pandemic, even commercially. It works by running an elastic cord below the jaw and a formable wire over the nose to encourage contact all around both mouth and nose.
Since the COVID-19 pandemic started, we’ve seen several attempts to create homebrew ventilators designed to address the shortage of these lifesaving machines. Unfortunately, most hackers aren’t terribly experienced when it comes to designing practical medical equipment. So while many of the designs might have appeared functional on the workbench, there’s little chance they’d get used in any official capacity.
The open source DP Ventilator is still clearly the product of a couple plucky hackers, but we think it shows a level of design maturity that’s been missing in many of the earlier attempts. Made primarily with 3D printed components, this mechanical device is designed to operate a hand-held manual resuscitator; essentially standing in for a human operator. This makes the design far less complex than if it had to actually pump air itself, not to mention safer for the patient since the resuscitator (often referred to as an Ambu Bag) installed in it would be a sterile pre-packaged item.
In the video after the break, you can see just how much thought and effort has been put into the device’s touch screen interface. With a few quick taps the medical professional operating the DP Ventilator can dial in variables such as breathing rate, pressure, and volume to match the patient’s needs. While the Arduino Mega 2560 at the machine’s heart wouldn’t pass muster for any regulating body in charge of medical devices, we think with a few more tweaks, this design is getting close to something that might actually be able to save lives.
The dongle is a DIY copy of one that Medtronic makes, which of course they don’t sell to anyone. It makes a three-way connection between the patient’s monitor, a breath delivery system, and a computer, and lets technicians sync software between two broken machines so they can be Frankensteined into a single working ventilator. The company open-sourced an older model at the end of March, but this was widely viewed as a PR stunt.
This is not just the latest chapter in the right-to-repair saga. What began with locked-down tractors and phones has taken a serious turn as hospitals are filled to capacity with COVID-19 patients, many of whom will die without access to a ventilator. Not only is there a shortage of ventilators, but many of the companies that make them are refusing outside repair techs’ access to manuals and parts.
These companies insist that their own in-house technicians be the only ones who touch the machines, and many are not afraid to admit that they consider the ventilators to be their property long after the sale has been made. The ridiculousness of that aside, they don’t have the manpower to fix all the broken ventilators, and the people don’t have the time to wait on them.
We wish we could share the dongle schematic with our readers, but alas we do not have it. Hopefully it will show up on iFixit soon alongside all the ventilator manuals and schematics that have been compiled and centralized since the pandemic took off. In the meantime, you can take Ventilators 101 from our own [Bob Baddeley], and then find out what kind of engineering goes into them.
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.
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”→
JPL, which is tightly partnered with the California Institute of Technology, designed the ventilator for rapid manufacturing to meet the current need for respiratory tools made scarce by the pandemic. The design process took only 37 days and was submitted for FDA approval around April 23rd. They call it VITAL — Ventilator Intervention Technology Accessible Locally — a nod to NASA’s proclivity for acronyms.
Operating under the idea that a Constant Positive Airway Pressure (CPAP) machine isn’t very far removed electrically or mechanically from a proper ventilator, [Trammell Hudson] has performed some fascinating research into how these widely available machines could be used as life support devices in an emergency situation. While the documentation makes it clear the project is a proof of concept and is absolutely not intended for human use in its current state, the findings so far are certainly very promising.
For the purposes of this research, [Trammell] has focused on the Airsense S10 which currently retails for around $600 USD. Normally the machine is used to treat sleep apnea and other disorders by providing a constant pressure on the lungs, but as this project shows, it’s also possible for the S10 to function in what’s known as Bi-level Positive Airway Pressure (BiPAP) mode. Essentially this means that the machine detects when the user is attempting to inhale, and increases the air pressure to support their natural breathing.
Critically, this change is made entirely through modifications to the S10 firmware. No additional hardware is required, and outside of opening up the device to attach an STM32 programmer (a process which [Trammell] has carefully documented), there’s nothing mechanically that needs to be done to the machine for it to operate in this breathing support function. It seems at least some of the functionality was already included via hidden diagnostic menus which can be enabled through a firmware patch.
As many of these CPAP machines feature cellular data connections for monitoring and over-the-air updates, [Trammell] believes it should be possible for manufacturers to push out a similarly modified firmware on supported devices. Of course, the FDA would have to approve of something like that before the machines could actually be used as emergency, non-invasive ventilators. They would also need to have viral filters installed and some facility for remote control added, but those would be relatively minor modifications.
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!