Low Pressure Drop Oxygen Flow Meter for the PLSS

The portable life support system (PLSS) of the advanced extravehicular mobility unit (AEMU) provides the necessary environment for a crew member to operate within the space suit. Within the PLSS, the oxygen ventilation loop provides carbon dioxide washout, gas temperature control, humidity control, and trace contaminant removal. Historically, there have been issues with the measurement of air flow for the oxygen ventilation loop. With the Apollo EMU, there were humidity issues with the implemented flow meter. For the Space Shuttle/ISS EMU, the flow sensor was a flapper/microswitch combination that only measured a discrete threshold for flow. This proposal provides an analog method to measure the continuous air flow. This new method meets the low pressure drop requirement and allows operation beyond low earth orbit (LEO) with radiation tolerant electronics. Per the solicitation, a prototype will be developed during phase I to verify this new technology.