Ventilator - DIY Development

Specs are hard to some by  -collating here
I think we will need:
A valve to switch inlet air
A valve to switch outlet air - needs low resistance
A flow sensor (maybe) - to detect how much air has gone in.
A pressure sensor - to detect when a breath has been initiated.


Test 1 - Valve
Can a bunnings irrigation valve switch air?
Answer - Yes
Test detail.  Connected to power supply and could hear the valve open and close.
Blew in and observed it would stop the air or pass it as intended.

Test 2 - Flow Sensor
We have a number of flow sensors at work.
I blew through each one to see what it would be like to breathe through one.

Most of them had too much resistance.
Second from the right with the orange tape was the only one that seemed OK to breathe through.

Need to find out where we got it from.