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I 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

I 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 ago
If 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 ago
  Whatever 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 ago
    300 pascals? That's darn near a vacuum. Did you mean not to let it drop more than 300 Pa below ambient?
    - adammunich 7y ago
      It cannot go under STP + 300 pascals, must always be positive pressure.
    - sudosysgen 7y ago
      If anyone's wondering, atmospheric pressure is 101 300Pa, so 300 Pa is extremely low.
ficklepickle 7y ago
Does 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 ago
  It 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 ago
    Make 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 ago
      The 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 ago
        Cheap 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 ago
Awesome work! What is civilpedia?
- justinclift 7y ago
  https://civilpedia.org https://civilpedia.org
justinclift 7y ago
As 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 ago
  Worse, 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 ago
I 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 ago
  Hey 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 ago
    Yes, 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 ago
Happy to help on EE side. PCB, firmware, verification, etc. https://www.linkedin.com/in/thenatefisher/ https://www.linkedin.com/in/thenatefisher/

jbay808 7y ago

If 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 ago
Whatever 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 ago
  300 pascals? That's darn near a vacuum. Did you mean not to let it drop more than 300 Pa below ambient?
  - adammunich 7y ago
    It cannot go under STP + 300 pascals, must always be positive pressure.
  - sudosysgen 7y ago
    If anyone's wondering, atmospheric pressure is 101 300Pa, so 300 Pa is extremely low.

ficklepickle 7y ago

Does 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 ago
It 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 ago
  Make 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 ago
    The 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 ago
      Cheap 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 ago

Awesome work! What is civilpedia?

justinclift 7y ago
https://civilpedia.org https://civilpedia.org

justinclift 7y ago

As 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 ago
Worse, 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 ago

I 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 ago
Hey 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 ago
  Yes, 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 ago

Happy to help on EE side. PCB, firmware, verification, etc. https://www.linkedin.com/in/thenatefisher/ https://www.linkedin.com/in/thenatefisher/