.Model A AKA AutoBMV will be a rapid response low/moderate capability ventilator that we will manufacture ASAP as an emergency stop gap. We already have multiple validated Model A designs, including from Harvey Hawes and MIT, that can deliver this functionality for < $200 per unit and are ready for manufacturing now.
the basic idea is to automate an ambubag i.e.
there are many approaches to make these possible, here's some links of working models
Student invention gives patients the breath of life
Model A docs will be shared soon (full package for all to use - working name AutoBVM)