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Fricker, John

Publications and source records attributed to Fricker, John.

5 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS2020

Standard Testing Procedure for Quantifying Breathing Gas Carbon Dioxide Partial Pressure for Extravehicular Activity and Launch, Entry, Survival Pressure Suits

This standard test and analysis protocol establishes the procedure for determining the partial pressure of inspired carbon dioxide (PICO2) exposure level experienced by persons operating a pressurized suit. The purpose of this Standard Testing Procedure (STP) is to describe the test conditions and procedures necessary to acquire data in support of certification that manufacturer submitted Extravehicular Activity (EVA) and/or Launch, Entry, Survival (LES) suit designs maintain safe levels of carbon dioxide (CO2) in the helmet during suited operations. The STP shall be used to measure the in-suit inhaled and exhaled dry-gas partial pressure of CO2 (PCO2), followed by calculation of the water vapor saturated PICO2 during the inhalation portion of the breathing cycle, while a human test subject is performing work at levels anticipated during suited operations in ground and flight environments. The procedure is designed to test the evaluated suit on a human test subject as a dynamic system, generate repeatable results under defined laboratory conditions, and perform consistent analysis on acquired samples.This STP is used to evaluate space suits in a hyperbaric environment (above atmospheric pressure). Changes would need to be made to the test equipment/setup to accommodate a hypobaric environment. There is no specific EVA or LES suit performance requirement to meet or pass/fail criteria associated with this STP.

Bekdash, Omar↗
NASA NTRS2018

Swing Bed Scrubber Design and Test Integration Results for Carbon Dioxide Removal in the Ventilation Test Loop 2.0

NASA is developing an advanced portable life support system (PLSS) to meet the needs of a new NASA advanced space suit. The PLSS provides the necessary oxygen, ventilation, and thermal protection for an astronaut performing a spacewalk. The PLSS ventilation subsystem is responsible for providing adequate carbon dioxide (CO2) and water vapor removal. To experimentally validate the performance of CO2 removal and advanced CO2 sensing systems, NASA Johnson Space Center developed the Ventilation Test Loop 2.0 (VTL2) and tested the Oceaneering Swing Bed Scrubber (SBS) that was fabricated and delivered under the Constellation Space Suit System Contract in 2015. The SBS was designed to continuously remove CO2 and water vapor from a space suit ventilation loop with a pair of thermally integrated amine beds that alternately adsorb and desorb water vapor and CO2. The SBS hardware was recently resurrected and reassembled to support a full battery of performance testing in the VTL2. This paper describes the design and development of the SBS and the VTL2 along with the performance test results of the SBS.

Ventilation Test Loop↗
NASA NTRS2007

Continuously Regenerable Freeze-Out CO2 Control Technology

Carbon dioxide (CO2) removal technology development for portable life support systems (PLSS) has traditionally concentrated in the areas of solid and liquid chemical sorbents and semi-permeable membranes. Most of these systems are too heavy in gravity environments, require prohibitive amounts of consumables for operation on long term planetary missions, or are inoperable on the surface of Mars due to the presence of a CO2 atmosphere. This paper describes the effort performed to mature an innovative CO2 removal technology that meets NASA s planetary mission needs while adhering to the important guiding principles of simplicity, reliability, and operability. A breadboard cryogenic carbon dioxide scrubber (Cryo Scrubber) for a closed loop cryogenic PLSS was developed, designed, and tested, and a conceptual design suitable for a PLSS was developed based on the results of the breadboard testing. The Cryo Scrubber freezes CO2 and other trace contaminants out of expired vent loop gas using cooling available from a liquid oxygen (LOX) based PLSS. The device is continuously regenerable, with solid CO2 being removed from the cold freeze-out surfaces, sublimated, and vented overboard. Duration is limited only by the supply of LOX stored in the PLSS. Simplicity, reliability, and operability are universally important criteria for critical hardware on long duration Lunar or Mars missions. The Cryo Scrubber has no moving parts, requires no additional consumables, and uses no electrical power, contributing to its simplicity and reliability. It is easy to use; no operator action is required to prepare, use, or shut down the Cryo Scrubber, and it does not require charging or regeneration. The versatility of the concept allows for operation on earth, the moon, and Mars, and in microgravity.

Fricker, John↗