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A Novel Mechanical Ventilator Designed for Mass Scale Production
- adammunich 7y agoI have been building something very similar to this! We have someone working on the controller PCB right now, and I am waiting for a few parts to arrive Friday so I can finish the proof of concept. Once the bugs are hammered out we will publish the design and build instructions on civilpedia. I can say for sure, the solenoid valves specified here in this paper are too small to work well enough. This problem has slowed our progress down by a week. If anyone has questions please ask them here.
- jbay808 7y agoIf I run a high-tech manufacturing facility that has some extra capacity these days, whose ventilator design should I start producing? It seems so many are springing up.
- adammunich 7y agoWhatever you can get parts for, I suppose. We chose parts you can get from Home Depot and Amazon/Ebay only, except for the PCB, which you will be able to make with hand-soldered components. Also: make sure you choose a design where it is not possible to over-pressure the lungs. Even so much as 1.5PSI can damage them permanently. As well, the design must never allow the pressure to drop below about 300 pascals (above STP), or the patient will eventually suffocate due to alveoli collapsing.
- phkahler 7y ago300 pascals? That's darn near a vacuum. Did you mean not to let it drop more than 300 Pa below ambient?
- adammunich 7y agoIt cannot go under STP + 300 pascals, must always be positive pressure.
- sudosysgen 7y agoIf anyone's wondering, atmospheric pressure is 101 300Pa, so 300 Pa is extremely low.
- ficklepickle 7y agoDoes your design also rely on pressurized medical air for operation? It sounds like this one is using an ESP32 microcontroller (described as 32 bit, arduino-compatible, WiFi+Bluetooth ). What microcontroller are you using? Is your design open source? Can you expand on the solenoid difficulties you experienced? Thanks! Edit: typo
- adammunich 7y agoIt can operate from any air source, we're using a free piston hydroponics compressor which is available from eBay/amazon vendors for $100. I have used these compressors for years with no reliability issues. We will be using an Arduino uno because they are so easily available, no wifi or bluetooth, last thing I'd want people to deal with is bluetooth bugs in a situation like this... The solenoids I have tried (many) are too restrictive for air flow, and after some minutes I felt suffocated when using them. Most solenoid valves don't have orfices greater than 2.5mm, and we found even 4mm was not enough. It will be open source, yes.
- mike_d 7y agoMake sure you are using a medical grade (oil and particulate free) compressor, because aerosolized machine oil and micro metals are super bad for people to breathe in.
- adammunich 7y agoThe free piston compressors don't use oil as far as I have been able to tell. I believe they are diaphragm pumps.
- mike_d 7y agoCheap compressors (even labeled oil free) will still have residue machine oil on internal surfaces from the manufacturing process. Chinese manufacturers usually surface coat metal to prevent rusting during shipping. It might not be enough to bother you or I, but if someone is respiratory compromised to the point they are on a vent, they really need medical grade oxygen.
- mrfusion 7y agoAwesome work! What is civilpedia?
- justinclift 7y agohttps://civilpedia.org https://civilpedia.org
- justinclift 7y agoAs an aside, your adammunich.com website just displays a "Please click the allow button to show you're not a robot" message. With no Allow button anywhere. With variations on it (but same problem) with each page load. Capture fail, or joke website?
- deleted 7y ago[deleted]
- jshevek 7y agoWorse, I'm getting a pop-up requesting I allow notifications. No, thank you. It seems that if I don't allow notifications, I can't view the site - and I'll keep getting the pop-up. This is one of the more intrusive and off putting experiences I've had on the first time load of a site. Edit: After clicking "Block notifications" about 10 times, and being redirected to a different "redfundchicken" address each time, I finally end on skyprize22.live, an obvious scam site. I believe adammunich.com redirects to a scam site.
- ksutariya 7y agoI have a bare PCB and PCBA CM that is still running. Let me know if that can help in any way. We can reprogram our lines to make any type of PCBs and assemble them (we have inventory of most standard components).
- Reelin 7y agoHey you appear to have been shadow banned back in 2017 for no reason I can see. I think you can email the support address to fix it?
- dang 7y agoYes, that was a mistake at our end and fixed now. All: if you see a banned user that shouldn't be banned, please let us know at hn@ycombinator.com. We try not to get this wrong, but we (and/or software) sometimes do. It's a big contribution to your fellow users to let us know so we can fix it.
- fallingmeat 7y agoHappy to help on EE side. PCB, firmware, verification, etc. https://www.linkedin.com/in/thenatefisher/ https://www.linkedin.com/in/thenatefisher/
- zackbloom 7y agoWe are working on a version of this which does not require any electronics: https://twitter.com/zackbloom/status/1242156904782139395?s=20 https://twitter.com/zackbloom/status/1242156904782139395?s=2... It uses fluid dynamics rather than a sensor system, simplifying manufacture at scale.
- justinclift 7y agoHow to potentially get involved, mainly from the point of view of "small scale" manufacture or helping with prototyping? Asking because a friend at one of the Uni's here in Melbourne, Australia is part of the team that looks after the Uni CNC machines (5 axis) and their 3D printers. The design in the twitter above looks like pretty much exactly what their 5-axis CNC machines can do. And they were already discussing potentially doing something with the 3d printers. So, might be a good fit to put them in contact with you? :)
- adammunich 7y agoI would like to ask you a few questions: Is PIP adjustable? Is PEEP adjustable? Is Tidal Volume adjustable? What sort of pressure regulation is required at the input?
- joeyspn 7y agoSome of your questions are covered in this doc: https://docs.google.com/document/d/1Hcuu-55q2a3_-LmBwg0uBdgMe-ZNPQ9jSdtrimCYazs/edit https://docs.google.com/document/d/1Hcuu-55q2a3_-LmBwg0uBdgM...
- chemeng 7y agoNice idea, better approach than I've seen popping up everywhere and clearly meant to be an emergency only device. I'm sure everyone has made clear how complicated and dangerous proper ventilation care is. I don't have time to get involved at the moment even though I would love to (expecting a newborn any day now), but a few thoughts. - Consider the failure-modes of the device. (If inspiration pressure set screw is not mechanically fixed and fails open, you will irrevocably damage the individuals lungs and likely kill them. Similarly, exhalation pressure drop could collapse alveoli and suffocate them). Could also put pressure relief/vacuum break valves on the device, but hard to do accurately and cheaply at small pressure ranges. - Fail indication. Need indicators in the field to understand whether device is functioning as designed or not. Particularly with high PEEP settings, visual indications of respiration are pretty much non-existent and no way to tell if pressures are causing barotrauma. - You may want to include guidelines for proper air supply intended for this device as well. Modern ventilation systems have fail-over and redundancy for all critical aspects (electricity, oxygen source, pressure regulation, etc) for respiration. This may be done at the device (taking feeds from multiple continuous supplies) or in the oxygen supply system (multiple compressors connected to a header system, high volume compressed oxygen tank etc).
- beenBoutIT 7y agoAnyone have any idea how different mechanical ventilators are from CPAP machines? A lot of people given CPAP machines can't tolerate CPAP therapy and as a result there's a shitload of barely used and unused CPAP machines all over the US.
- gamedori 7y agoThe ventilators used for severe cases of COVID run at much higher pressures.
- killjoywashere 7y agoIf you have not submitted yet, consider submitting to the DoD Hack-a-Vent challenge: https://vulcan-sof.com/login/ng2/submission?collectionUuid=24028d51-267f-4f10-a455-230a13055c12 https://vulcan-sof.com/login/ng2/submission?collectionUuid=2...
- ineedasername 7y agoWhy do we need more designs? We have designs. We need more production. If we need simpler designs, brush off the proven designs for 40 year old emergency field medicine ventilators and manufacture them. To paraphrase, designs are easy; manufacturing is hard. Stop tossing around unproven designs that are unlikely to roll off the assembly line any time in the next few months and focus on getting current manufacturers anything they need to scale existing production. It's not like there aren't simpler, emergency-ready rapid deployment models already on the market: use them! [0] [0] http://www.alliedhpi.com/mcv.htm http://www.alliedhpi.com/mcv.htm
- jbay808 7y agoCan my factory manufacture these designs?
- ineedasername 7y agoI don't know anything about your factory. But if you mean, can they do it from the perspective of IP/proprietary data etc., then that's the bottleneck to solve. The DPA could easily cut through that bottleneck if existing factories could quickly be retooled to manufacture existing, proven & approved designs. The alternative is to retool to produce novel, unproven, unapproved designs. If you have a factory, great! You'll need to retool it though. Which design would you rather target? A simple, proven, approved design tailor made for this sort of situation? Or the simple, tailor made, but unproven new ones that are being thrown together in a few weeks?
- _curious_ 7y ago"Which design would you rather target? A simple, proven, approved design tailor made for this sort of situation? Or the simple, tailor made, but unproven new ones that are being thrown together in a few weeks?" Perhaps both paths will prove necessary and valued?
- adammunich 7y agoWhat capabilities does it have?
- BooneJS 7y agoI understand these devices take 2-3 years not reach market. What’s the risk that some of these devices aren’t effective or too overpowering? Is there a test harness that can grade these devices?
- robomartin 7y agoUnbelievable stuffy I keep reading on ventilators. Just unbelievable. If you want to kill people by the thousands, please continue. The good news is no medical professional in their right mind would use one of the hot messes so many are "inventing". Parts from Home Depot? Really? These are life critical systems designed with serious fault tolerance in mind. Home Depot parts, randomly sourced solenoids, valves and fucking Arduino's? Has everyone gone insane? Here, go read the Wikipedia page on ventilators: https://en.wikipedia.org/wiki/Ventilator https://en.wikipedia.org/wiki/Ventilator Let me highlight a few sections. Like this one: "Because failure may result in death, mechanical ventilation systems are classified as life-critical systems, and precautions must be taken to ensure that they are highly reliable, including their power-supply." "Mechanical ventilators are therefore carefully designed so that no single point of failure can endanger the patient. They may have manual backup mechanisms to enable hand-driven respiration in the absence of power (such as the mechanical ventilator integrated into an anaesthetic machine). They may also have safety valves, which open to atmosphere in the absence of power to act as an anti-suffocation valve for spontaneous breathing of the patient. Some systems are also equipped with compressed-gas tanks, air compressors or backup batteries to provide ventilation in case of power failure or defective gas supplies, and methods to operate or call for help if their mechanisms or software fail." I mean, seriously, read that again right now. If you have zero experience in fault-tolerant design of electronics, mechanics, pneumatic, hydraulic and software systems, please recognize the dangers of the Dunning-Kruger effect and stop. If that wasn't enough, there's this: "In Canada and the United States, respiratory therapists are responsible for tuning these settings, while biomedical technologists are responsible for the maintenance. In the United Kingdom and Europe the management of the patient's interaction with the ventilator is done by critical care nurses." In case the point isn't obvious, what this means is that certified professionals have to operate these devices. They are not going to get anywhere close to a pile of parts from Home Depot and the local auto repair shop. They are trained to operate reasonably standardized equipment and expect form, function and reliability that comes with time-tested, certified and well proven professionally manufactured equipment. Want to build something to help? Maybe figure out how to make hospital beds. My guess is there's far less likelihood of killing people with a frame and a matress than with a pile of Home Depot parts and an Arduino pretending to be a ventilator. Why are these posts even permitted on HN? This is unproductive dangerous quackery. Nobody is going to invent anything useful. Go help existing companies stamp out more units of their designs. I'm sure they can use the help.
- anonsubmit2671 7y agoEven AvE got into the fabricobbled ventilator prototype business. https://youtu.be/N1OFMZDNKvU https://youtu.be/N1OFMZDNKvU https://youtu.be/t324iJOYoXI https://youtu.be/t324iJOYoXI
- hoseja 7y agoAnd it looks rather similar to this one.
- DoreenMichele 7y agoJust as a kind of PSA: In light of ventilator shortages, I encourage you to look up non invasive airway clearance methods. These are medically recommended for people with serious, chronic lung issues. They've been around a long time. I'm not seeing them get much attention compared to the ventilators.
- rkagerer 7y agoThis paper is 7 pages long and has only 4 diagrams. Here are the testing videos: https://tinyurl.com/uurapy3 https://tinyurl.com/uurapy3 I applaud the initiative, but even for something macgyvered together in a hurry, I think a more rigorous approach is needed before deploying something like this en-mass.
- rapjr9 7y agoI've read that one ventilator requirement for COVID-19 is an output filter that prevents the virus (and other viruses and bacteria) from getting into the room air. Otherwise a ventilator is pumping virus into the room air which increases risk for other patients nearby and medical personnel. I'd imagine that worst case these ventilators might be used in large arena's filled with beds rather than positive pressure ICU rooms. Maybe HEPA filters for air purifiers would work? Or HEPA vacuum bags? Or the big filters trucks use for air intake, I think those were used in some early HEPA air filter devices. Not sure if they are fine enough filtering to stop a virus though.
- paulgerhardt 7y agoI recently saw the three component ventilator[1] and was immediately impressed. No electronics - huge plus for scalability 1-to-N - one ventilator can serve a hundred or more intubated patients - again a massive boon to scalability and dovetails nicely with the armies approach to retrofit empty hotel rooms with negative pressure kit. PEEP and moisture control - this was in the version 2 model Love the groundswell of new ideas here. Traditional designs were made for individual patients with and a broken procurement process - these new versions can address a large volume of patients in a distressed supply chain. [1] https://youtu.be/N1OFMZDNKvU https://youtu.be/N1OFMZDNKvU
- Yoric 7y ago> 1-to-N - one ventilator can serve a hundred or more intubated patients - again a massive boon to scalability and dovetails nicely with the armies approach to retrofit empty hotel rooms with negative pressure kit. That's... scary. I seem to remember that each ventilator needs to be tuned to a patient's pulmonary capacity. Otherwise, you risk either not providing enough air or exploding the lungs.
- naasking 7y agoCouldn't that be handled my modifying the oxygen mixture per patient? My concern would be contamination between patients on the same system. People are ventilators are typically immune compromised. The positive pressure helps avoid this, but I'm not sure it's enough pressure.
- aichi 7y agoThere is Czech initiative to provide same and being available under Open Hardware license soon. https://www.corovent.eu/ https://www.corovent.eu/
- RobertoG 7y agoAnother one: https://www.oxygen.protofy.xyz/ https://www.oxygen.protofy.xyz/
- helsinkiandrew 7y agoAs many have said it seems everyone is creating designs for ventilators, but few are producing large numbers that are being used. But I'd guess that 99% of the effort required to create a ventilator is not the design of the mechanism pumping air into lungs but guaranteeing it is reliable, maintainable, easy to use, is hygienic and can be cleaned safely, obeys regulations and manufactured. It doesn't matter if there's a crisis on or not - hospitals will get sued if your Heath Robinson style ventilator breaks and kills a person, however sick that person is.
- fsh 7y agoIt is also worth noting that the fatality rate of cases that get artificial ventilation is about 50 % even in ideal conditions. While it can save a lot of lifes, keeping the total number of cases low is still absolutely crucial.
- helsinkiandrew 7y agoAgreed, It would make seem to make more sense for people to think about how to make people stay further apart, or designing and creating face masks or other 'gadgets' that stopped the spread of the disease.
- nicoburns 7y agoGiven that the recommended distance is 2 metres, I thought it might be fun to provide everyone with a metre stick, and if you can only just touch sticks then you're the right distance away. + it gives an alternative to the handshake!
- Mvandenbergh 7y agoI understand people's needs to do something and if this helps people feel better I am all in favour of it. The engineer in distress builds. But this design is missing some fundamental things which makes me wonder if they've really understood the requirement. The first is that there is no flow monitoring so no way to adjust tidal volume. Since this is the most important parameter to adjust and control in treating ARDS, that lack is worrying. Their taxonomy of ventilatory modes is wrong. All the diagrams and text refer to a non-invasive ventilation using a mask but that is not where the greatest shortage is. There are a lot of BIPAP and CPAP machines which can be used for that sort of thing. There is a consistent reference to a PEEP of 5cm which is too low for the desired use case. I know the design is adjustable but the fact that this is not acknowledged is again a sign that they may not have understood what is needed. There is no blending arrangement for running on an O2/air mix. I don't understand why they did not add that. I don't object to this stuff, it's all a bit of fun, but the ventilator shortage is going to be fixed if it is by combining the resources of idled factories with mass production capabilities with the knowledge of ventilator manufacturers. When we did this in WWII, we did not ask Ford and GM, "Could you build us a bomber, please?". They collaborated with plane manufacturers to convert their factories to produce existing designs. If I was in charge of this effort, here is what I would do: First, in the near terms, make sure that existing manufacturers have what they need to boost their own production. -People who work in aerospace (or F1 racing, of a few other things) for instance have experience in hand assembly of critical components following procedures precisely. This is a better resource to draw on than other manufacturing workers such as auto workers. You could bulk out the assembly teams in existing manufacturers with these people. -What parts will they soon run out of? If their supply chain can't deliver, what alternatives can be rapidly qualified for use? Valves and sensors could be sourced from non-medical-grade manufacturers, preferably aviation or other safety critical because again - they live in a similar world as far as traceability and quality goes. In parallel you work on a basic design that meets the requirements of treating ARDS. You do that using the engineers who design ventilators anyway, together with supply chain and manufacturing experts from your other industries so that you design something that the supply chain can either produce or more likely they can produce sub-assemblies and/or parts.
- helsinkiandrew 7y agoAs useful background, here's the UK's Medicines Agency "Specification for Rapidly Manufactured Ventilator System (RMVS)" that need to be followed before any hospital would use one of these devices: https://www.gov.uk/government/publications/specification-for-ventilators-to-be-used-in-uk-hospitals-during-the-coronavirus-covid-19-outbreak https://www.gov.uk/government/publications/specification-for...
- gridlockd 7y ago"Our design is optimized to permit large sale production in short time and at a limited cost, relying on off-the-shelf components, readily available worldwide from hardware suppliers." Those shelves, I'm afraid, are going to be empty. Manufacturing is optimized for "just-in-time" production, not "just-in-case" stockpiling. Perhaps I'm the wrong person to consult, but I wouldn't know how to procure ample amounts of "Medical Care Flow Meters" or "Spirometers". Somebody figure out a way to solve the problem with plastic bags, PET bottles, outdated smartphones and old PC fans. I've got a strategic stockpile of those to give away, just like every other nerd on the planet.
- mariopt 7y agoI noticed the "O2 Therapy Humidifier" and other components. How does this ventilator fares against a AMBU bag ventilator? Right I'm making an effort to acquire DIY to build a ventilator that squeezes an AMBU bag. I found it incredible easy to make and scale, total cost around 300 euros/324 USD.
- RobertoG 7y agoMaybe you would be interested in this: https://www.oxygen.protofy.xyz/ https://www.oxygen.protofy.xyz/
- rogerrethinker 7y agoI propose a shared manifold ventilator based on plumbing and pneumatic parts and pieces. I just wanted to point out that such a device could handle 20 or more patients at once and uses well-established principles of reliability. https://bit.ly/c19ventilator https://bit.ly/c19ventilator