Pulse-modulated dual-gas control subsystem for space cabin atmosphereAn atmosphere control subsystem (ACS) was developed for use in a closed manned cabin, such as the Space Shuttle Orbiter. This subsystem uses the Perkin Elmer mass spectrometer for continuous measurement of major atmospheric constituents (H2, H2O, N2, O2, and CO2). The O2 and N2 analog signals are used as inputs to the controller, which produces a pulse-frequency-modulated output to operate the N2 gas admission solenoid valve and an on-off signal to operate the O2 valve. The proportional controller characteristic results in improved control accuracy as compared with previously used on-off controllers having significant dead-band. A 60-day evaluation test was performed on the ACS during which operation was measured at various values of control setpoint and simulated cabin leakage.
Document ID
19740056369
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Jackson, J. K. (McDonnell Douglas Astronautics Co. Huntington Beach, Calif., United States)
Date Acquired
August 7, 2013
Publication Date
July 1, 1974
Subject Category
Biotechnology
Report/Patent Number
ASME PAPER 74-ENAS-13
Meeting Information
Meeting: Intersociety Conference on Environmental Systems