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The Total Off-gassing test purpose is to determine the identity and quantity of trace gas contaminants offgassed in areas of spacecraft where the crew will breathe the atmosphere. Two different air sampling methods were adopted in parallel during the off-gassing tests on the Multi-Purpose Logistics Modules (MPLM) by Alenia Spazio. The first method, based on NASA (National Aeronautics and Space Administration) requirements, foresees storage of collected air samples into stainless steel pressure cylinders. The second method proposed by ESA (European Space Agency), uses trace contaminants adsorption on Carbopack™ filled ceramic tubes. Sample lines route the samples collected inside the MPLM cabin, to the respective external collection points. Successively, the stored samples are chemically analyzed by Gas Chromatography / Mass Spectrometry (GC/MS) techniques and the module offgassing rates are calculated.

The Columbus Attached Pressurised Module (APM) is intended to support a shirt-sleeve environment for crew activities. Top level requirements therefore define a cabin air temperature and humidity range (the so-called “Comfort Box”), extreme air velocities for ventilation in the centra aisle, maximum mean radiant temperature of the cabin walls. Air temperature selectability has to be ensured with adequate accuracy across the whole range. The APM environmental control system, in particular the Temperature and Humidity Control (THC) system, is designed and verified against these parameters. Cabin thermal conditions can be evaluated by the APM Integrated Overall Thermal Mathematical Model (IOTMM), representing the general thermal behaviour of the APM, including the THC system. Heat loads due to APM subsystem equipment and payloads, solar flux and the crew itself have been considered in the analyses.

As a consequence of the reduced funding by the ESA Member States contributing to the Columbus and Manned Transportation Programmes, the Columbus Project has undergone two major cost reduction exercises since 1993. An important cost reduction was achieved in mid '93 by downsizing the Attached Pressurized Module (APM) from 8 to 5 Double Racks equivalent length. To reduce the costs further, in 1994 the European space industry took the opportunity of exploiting specific features of the APM common with those of other projects, potential candidates being the Mini Pressurized Logistic Module (MPLM), developed by the Italian Space Agency (ASI) for NASA, or the European developed Russian Data Management System (DMS-R). In addition simplifications in System Function and in the Verification approach and maximum use of Off-the-Shelf and Commercial/Aviation/Military (CAM) hardware were investigated.

The Mini Pressurised Logistic Module (MPLM) includes an Environmental Control and Life Support System (ECLSS), whose general purpose is to guarantee a comfortable environment for the Crew. In particular, among the functions of the ECLSS, there is the provision of a correct ventilation in the habitable area of the Module and an air flow adequate to support fire detection in powered zones. These tasks are carried out by an air ventilation system mainly composed of a fan, eight cabin diffusers and a ducting system. In addition, the ECLSS furnishes, through a dedicated distribution system, the capability to suppress fire by release of the Carbon Dioxide contained in a portable fire extinguisher.

Microorganism accumulation and growth onboard a spacecraft may impact adversely on crew efficiency and safety as well as system, subsystems and payload. The results of test campaigns performed at Alenia Spazio in Summer 1993 are reported here. From them, some simple and effective prevention methods to be applied during the manufacturing and integration phases of a pressurised spacecraft have been identified and are here discussed. Although data obtained from Earth experience may be considered useful, it is uncertain and unfit for space station operational lifespan. Therefore, it is necessary to build a model of the phenomenon, able to provide a series of quantitative data as a function of different parameters related to environmental characteristics, crew, and on-board activities.

The Mini Pressurised Logistics Module (MPLM), a cooperative project between NASA and ASI that will be designed, developed, produced, integrated and delivered by Alenia, is a pressurised volume devoted to the resupply and return of Space Station (SS)containerized cargo requiringapressurised environment, via the National Space Transportation System (NSTS). As a servicer for the SS, the MPLM will have to accomplish several trips between Earth and SS in support of logistic needs. Since the active payloads launched with MPLM (freezers and refrigerators) require resources during the transportation phase inside the NSTS, the MPLM has the peculiar capacity to exchange power, data and fluids with the Orbiter before docking to SS. Once docked to SS, the MPLM will be required to provide its full performance, making use of the resources available from the SS Node; nevertheless, in this phase some of the MPLM functions are demanded from the SS.

A Human Factors Engineering (HFE) analysis has been involved in the design process of the Mini Pressurized Logistics Module (MPLM) for the International Space Station (ISS) since the beginning, as an integrated part of the design support activities. The support of HFE in the configuration process has been directed towards the optimization of the MPLM design through the analysis and evaluation of all the interfaces occurring in the module - nominal and non-nominal - between the crew, the system and the subsystem equipment. In order to identify and analyze all the crew interfaces occurring inside the module, a systematic approach, involving different disciplines, is necessary. The integration of three different tools such as computer simulation, task analysis and mock-up test activities has been employed as an organic unit, in order to establish a comprehensive collection of useful data.

In the overall planning of a manned mission to Mars, all the issues related to human involvement are critical. To a certain extent, they dictate the most severe constraints on the mission scenario and spacecraft architecture. Despite this unanimously recognized importance, limited efforts have been devoted up to now to dedicated research activities on human-related aspects, partially neglected w.r.t. more technical areas like orbital dynamics, propulsion, power generation, etc. This paper summarizes the major results of a survey on the human factors of long duration missions performed by Alenia Spazio in the frame of an ESA study, MARSEMSI, whose aim was to identify possible scenarios and related infrastructure requirements for a manned mission to Mars.

The COLUMBUS Attached Pressurized Module (APM) is the European orbiting laboratory which will be permanently attached to the International Space Station Freedom (SSF). It is designed to provide a range of laboratory facilities in a microgravity environment for payload experiments originating from the international payload-user community. The individual payloads will in general be mounted in payload racks which can be accommodated in fixed positions on the left and right hand sides of the laboratory and in the ceiling. International standard payload racks (ISPR) can be located in any of the SSF laboratory elements and find compatible interface conditions subject to agreements made between the international partners (NASA, NASDA and ESA). The APM design provides a water cooling capability by means of moderate temperature (MT) and low temperature (LT) pumped fluid loops. The cooling loops serve both the APM essential subsystem equipment as well as the payload users.

Every kind of human activity in space is made at least different on often more difficult by the peculiarity of the environment, characterized by the almost complete lack of gravity. It is difficult to realize, when staying with our own feet firmly on ground, how life could be altered by the absence of the ever present force of gravity! Among all the psychological faculties directly affected by microgravity, easy and quick orientation, and object identification (as they depend on the visual environment) are analyzed. This work follows on from previously published work (cf. ICES '91) by the authors, highlighting the importance of sensible groundrules in color choice for a space environment, to optimize the above-mentioned capabilities, to which crew performance reliability and safety are directly linked.

The Mini Pressurized Logistic Module (MPLM) is designed to transport supplies and return cargo requiring a pressurized environment to and from the Space Station Freedom (SSF) via the National Space Transportation System (NSTS) Shuttle. The MPLM provides accommodation for a number of cargo racks, including two Freezer/Refrigerators (F/Rs) and one subsystem rack. The maintenance of the habitable conditions for the crew and the control of the MPLM thermal environment are carried out by the Environmental Control and Life Support System (ECLSS) and the Thermal Control System (TCS). The ECLSS and TCS functional concepts are tailored to the peculiarities of the MPLM design, based on mass and volume minimization, maximum simplification and exploitation of the resources available at the SSF interface.