So, how do you make a ventilator?
To me, who knows nothing about the subject, it sounds like you need some tubing and valves, an air pump, some electronics , some switches and pots to control things and a case to hold it all together.
So, a steam engine builder, a hot -air engine builder, an Aurdino enthusiast, someone who has fitted a VFD to his lathe, anyone who has made a toolbox, and a martinet to organise things.
We have all the skills on this forum!
I guess there must be more to it than that, but they are asking JCB to make them, and it seems a long way from an earth mover to medical equipment, so perhaps it's not rocket science.
Not entirely seriously
Rod