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Design and implementation of a computer aided test and a knowledge base/object oriented database for Space Station Freedom is discussed. Described within the paper is the design and development of “C”/SQL language software and programmable logic needed to acquire data and provide system control functions. Creation of a user interface for an intelligent report generator, a database of test anomalies with interactive alarming and an expert system for system trouble-shooting is outlined.

General plans for testing of a regenerative ECLS system in a Module Simulator at MSFC have been been discussed in a previous paper; preliminary test results are given in this paper and a companion by Mr. McAlister. Subsystems for this series of tests have been provided by Life Systems, Inc., AiResearch Manufacturing Co., Umpqua Research Company, Lockheed, and Hamilton Standard. Results of testing those subsystems provided by Hamilton Standard are covered in the other paper. Subsystems have been installed in the Module Simulator in accordance with the test plan. These include the 4-bed Molecular Sieve, the Static Feed Water Electrolysis Subsystem, and the Urine Pretreatment/Mixing Unit to be covered herein.

Space Station Freedom (SSF) is required to distribute water for use and reprocessing. As SSF is erected, the configuration of the water distribution system changes along with specific functions. Therefore the interaction of the various components changes radically. Also, these components are taken off-line intermittently for maintenance (such as filter replacement). In order to analyze these interactions, a simplified steady state computer model was prepared. Parameters such as set points and storage tank capacities were revised based upon new performance understanding. The model was built using a Lotus 1-2-3 program. The model, making extensive use of macros, was iterated over thousands of hours of simulated SSF water processing in orbit. The data was stored and plotted. With the aid of the results of this modeling, the flight design was refined to a high level of maturity.

Space Station Freedom (SSF) will be required to vent water during non-quiescent periods. During Man Tended Configuration (MTC), before the Environmental Control and Life Support System (ECLSS) water loop is closed, humidity condensate will be periodically vented. At Permanently Manned Configuration (PMC), water will be vented on contingency if there is excess water on SSF. The thrust due to venting must be minimized to be considered non-propulsive. Also, ice formation and clogging of the vent nozzle must be avoided. Many aspects of the Space Shuttle water vent design were utilized in development of the preliminary SSF water vent design presented in this paper. Design modifications which improved the shuttle vent as well as those necessary for SSF are discussed. The exterior vent location, direction and environment on SSF are unique compared to previous space water vent designs. From data collected in the vent tests and analyses, a finalized SSF water vent design will be developed.