Model originally uploaded to Thingiverse at https://www.thingiverse.com/thing:4252782.

This membrane is just a useless two part assembly.

Had some ideas with an excenter disc, driven by a speedcontrolled motor and in a stern like assembly with (maybe varying) volumina for emergency respiration use with lowest available materials.

Use it if it could be used. It is unprinted so far.

membrane TPU / TPE vessel PETG / PLA / ABS ...