[markhollis]

I've been following the developments of these ventilators pretty closely, particularly of these using a ventilator for multiple patients.

The hard part is not the ventilation mechanism itself, but the specifications. Those ventilators must be controlled precisely, they must take into account the characteristics of COVID-19 patients. There is some overlap with ventilation for ARDS. The more you read into this subject, the more you realize how absolutely scary it is to actually design such a project. Lots of parameters have to be taken into account.

Read on mechanical ventilation. https://en.wikipedia.org/wiki/Mechanical_ventilation

3D printed parts that where the air flow through must be air-tight.

[raphman]

Yeah, I' been following the various projects, too. As far as I can see, many people underestimate that ventilators are just one necessary tool of many in intensive care. Sure, you can whip up a proof-of-concept prototype using a bag-valve mask, a stepper motor, and an Arduino. However, most COVID-19 patients will be multimorbid and require lots of attention. As multiple healthcare experts have mentioned so far, the real bottleneck are highly-qualified intensive care doctors and nurses.

Do you really want to give these people a new ventilator with which they are not familiar, which may lack features they need, and which might break down or malfunction in an unfortunate moment?

Maybe there is a place for such simple ventilators outside intensive care, e.g., as support for people who are able to breathe on their own and do not necessarily require mechanical ventilation, AND who are in a place without nasal O2 supply?

[rootusrootus]

If someone didn't need mechanical ventilation but would benefit from some assistance, couldn't they use a CPAP? There sure are a lot of those in use across the world.