From Rado (on his Facebook page):
We managed to assemble an improved prototype. We think the concept is good, but it can be significantly simplified. We hope that there are engineers among those who read this post to help us with ideas on how to improve it.
- We added a second shoulder to press AMBU bag element, which improves the principle of work (MIT also released a similar two-shoulder prototype). Meanwhile, we saw the prototype of colleagues from Spain, which gives us ideas for further improvements to our: https://www.3dnatives.com/en/3d-printed-respirator-230320205/
- We’ve strengthened the mechanics.
- Control module elements have arrived. We are trying to do a circuit board design (PCB) and develop a few prototypes. Unlike most similar projects, we are working on our own integrated scheme with simple PIC controllers (instead of Arduino, what we know many other teams use). At first glance, it’s illogical, but when attempting validation and certification, it would be much easier because we have complete control over the code and its execution from the hardware.
- We also develop flow meter to be used instead of expensive ready solutions.
- The greatest difficulty is in t. Pomegranate. PEEP mode, where exhale pressure is controlled, which proves to be very important for treatment. This will complicate the whole apparatus, probably having to add a small compressor and / or assumed that the centralized compressed air system of hospitals (something we avoid) can be used.
Next up is optimization of the mechanism: to remove as many wear items as possible and try to gather it into a smaller space. We also need to choose an electric motor as well as materials for the components themselves.
> The sharpest need currently continues to be on the team to include a person who has dealt with validation / certification of medical equipment.