Your channel is quite interesting, yet with very few views. I hope that will change in a future as you add more content. Note that I'm not concerned about how medical-grade machines of this sort work, but given such critical application, it seems to me it would be better to design it around mechanisms that would allow the system to be cyclic, hence, needing only a regular DC motor turning in a single direction all the time. A magnet stuck to the shaft that drives the belows and a coil in a linear fashion along it's path, could help to monitor the machine is running with discrete components, rather than also relying on firmware for this. As a side note, it turns out I've also been a time thinking of just this, which is driving a pneumatic piston with a single DC motor (running continuously in a single direction), yet producing a reciprocating motion. While I've found out many ways of doing it, not yet one that I really liked, though I'm not yet quite there either, and it needs thorough thinking before I decide on one, or come up with another method. All the best!
@antalz3 жыл бұрын
The main reason I chose electronic control is that you want to be able to set the tidal volume, which means how far the piston moves. As far as I know you can only do that electronically, if you want to user to be able to change the tidal volume. I have seen some reciprocating mechanisms to drive a machine like this, but respiratory therapists advised us that user-selectable tidal volume is absolutely required, and documents like the MHRA emergency ventilator specification said the same thing. The other reason for electronic control is that electronics are extremely reliable and affordable nowadays. There is a risk of code bugs, but hardware failures of microcontrollers or pressure sensors and such are extremely rare. Stepper motors are likewise extremely reliable. Brushed DC motors are too, if you replace the brushes often enough, but there is some concern with the dust from the brushes combined with the pure oxygen these machines work with. I do think working on these machines and other creative viewpoints are still very valuable. Covid may appear to be nearing the end here in Europe, but the situation is still extremely dire elsewhere, and now respiratory virusses may also pop up. We really should be prepared next time.
@michaelmolter88282 жыл бұрын
Any benefit of two steppers you have to synchronize over just two pulleys and a timing belt?
@michaelmolter88282 жыл бұрын
Ah, answered the question a little later.
@Energya014 жыл бұрын
Looking pretty good so far. Ticks most of the boxes as outlined in e.g. kzfaq.info/get/bejne/bdx8g8iXrb-7oI0.html
@antalz4 жыл бұрын
I think the most important point he made is to first figure out the requirements before you go building. With AirToAll we got to speak to some respiratory therapists, and there are tons of resources online about what a ventilator is supposed to do and why. It seems a bit silly to me to start building before you've figured out what the job even is.