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Technical Paper

A Graphical Workstation Based Part-Task Flight Simulator for Preliminary Rapid Evaluation of Advanced Displays

1992-10-01
921953
Advances in avionics and display technology are significantly changing the cockpit environment in current transport aircraft. The MIT Aeronautical Systems Lab (ASL) has developed a part-task flight simulator specifically to study the effects of these new technologies on flight crew situational awareness and performance. The simulator is based on a commercially-available graphics workstation, and can be rapidly reconfigured to meet the varying demands of experimental studies. The simulator has been successfully used to evaluate graphical microburst alerting displays, electronic instrument approach plates, terrain awareness and alerting displays, and ATC routing amendment delivery through digital datalinks.
Technical Paper

A Lubrication System for Space Vehicles

1964-01-01
640007
The conditions of space environment, especially high vacuum, and the high degree of reliability required are two important aspects of the problem of lubrication for space vehicles. Experiments have been made using conventional designs to achieve high reliability, and a narrow gap seal with a calculated oil loss instead of a rubbing contact seal. Two systems are evolved from theoretical considerations derived from the kinetic theory of gases. The experiments have validated the usefulness of this approach.
Technical Paper

A System-of-Systems Approach to Aerospace Ground Equipment

1999-10-19
1999-01-5555
The Air Force Research Laboratory Deployment and Sustainment Division (AFRL/HES), in coordination with Arthur D. Little, Inc., has undertaken a system-of-systems approach to defining and designing aerospace ground equipment (AGE). This method is usually used to take advantage of the open architecture nature of ne and developing electronics through modular design. This paper discusses how we applied it across the electronic, mechanical, and structural aspects of AGE to research and develop a new concept to meet the burgeoning needs of the 21st century Air Force.
Technical Paper

ARES - ESA's Regenerative Air Revitalisation Experiment on the International Space Station

2008-06-29
2008-01-2093
ESA has been developing regenerative physicochemical air revitalisation technology for more than 20 years. The effort is now maturing into a flight demonstration experiment which is planned to be located in the Columbus module on ISS. The experiment shall be sized for a crew of three. It will comprise a CO2 concentration assembly, a Sabatier reactor and an electrolyser. The paper describes the adaptation of ARES to the available Columbus interfaces as well as ARES development status, performances, benefits to the ISS and operational agreements with ISS partners.
Technical Paper

ATV Thermal Control System

2004-07-19
2004-01-2469
The Automated Transfer Vehicle (ATV) Thermal Control System (TCS) has the task to ensure the required internal environment at level of pressurized module and to thermally control the not pressurised modules and installed equipment, using passive and active control means, in response to the relevant applicable requirements. The ATV vehicle is assially subdivided into three main modules: the Integrated Cargo Carrier (ICC), the Equipped Avionics Bay (EAB) and the Equipped Propulsion Bay (EPB). Each of these modules present elaborated and specific thermal design solutions, to satisfy the different required operative tasks. The extensive thermal analysis campaign performed at ATV vehicle level and in progress for the next Qualification Review (QR) to justify and support the thermal control design solutions and verification status is described.
Technical Paper

Air Quality Monitoring by Open Path Fourier Transform Infrared (FTIR) Spectrometry

1997-07-01
972391
The feasibility of using open path Fourier transform infrared (OP-FTIR) spectrometry as an ambient air sensor on spacecraft was examined. OP-FTIR is a valuable monitoring technique because the sensor requires no sample preparation or separations and compositional information obtained is along a path rather than at a sampling point. OP-FTIR monitors and quantitates in real-time, offers high sensitivity, and detection is compound-specific. The data analysis, data reduction, and hardware requirements were investigated and potential applicability of chemometric methods and state-of-the-art commercial hardware systems were discussed.
Technical Paper

Anthropometric and Blood Flow Characteristics Leading to EVA Hand Injury

2009-07-12
2009-01-2471
The aim of this study was to explore if fingernail delamination injury following EMU glove use may be caused by compression-induced blood flow occlusion in the finger. During compression tests, finger blood flow decreased more than 60%, however this occurred more rapidly for finger pad compression (4 N) than for fingertips (10 N). A pressure bulb compression test resulted in 50% and 45% decreased blood flow at 100 mmHg and 200 mmHg, respectively. These results indicate that the finger pad pressure required to articulate stiff gloves is more likely to contribute to injury than the fingertip pressure associated with tight fitting gloves.
Technical Paper

Bio-Suit Development: Viable Options for Mechanical Counter Pressure

2004-07-19
2004-01-2294
Human explorers of planetary surfaces would benefit greatly from a spacesuit design that facilitates locomotion. To aid in the development of such an extravehicular activity suit, a design effort incorporating the concept of mechanical counter pressure (MCP) was undertaken. Three-dimensional laser scanning of the human body was used to identify the main effects of knee flexion angle on the size and shape of the leg. This laser scanning quantified the changes in shape that must be supported by an MCP garment and the tension that must be developed to produce even MCP. Evaluation of a hybrid-MCP concept using inextensible materials demonstrated strong agreement between experimental data and a mathematical model with rigid cylinder geometry. Testing of a form-fitting garment on the right lower leg of a subject demonstrated successful pressure production. Further research is required to evaluate how evenly pressure can be distributed using the hybrid-MCP concept.
Technical Paper

Biological Life Support within ESA Past and Future developments.

2000-07-10
2000-01-2338
For the last 10 years, ESA has initiated Life Support activities to prepare long-term manned missions. Although a large part of these activities were based on physico-chemical technologies, biological processes were considered as well. A few projects were initiated: air contaminants removal (e.g. BAF) up to the complete and complex approach of artificial ecosystems (e.g. MELISSA). In order to make a complete survey of the existing developments, to evaluate their advantages and weaknesses, to identify the needs of future projects, as well as to understand the interest of industry, an Advanced Life Support Workshop has been organised in April 1999 by ESA. This paper reviews the existing developments and presents the recommendations of the workshop. A specific part is devoted to the projects in collaboration with the ESA Life Sciences community and the results of the 1999 announcement of opportunity, which included Biological life Support.
Technical Paper

Chain Representations of Dimensional Control: A Producibility Input for Concurrent Concept Design

1998-06-02
981846
Two critical milestones that must be achieved during concept design are 1) definition of a product architecture that meets performance, producibility, and strategic objectives, and 2) estimation of the integration risk in each candidate concept. This paper addresses these issues by describing the role played by the producibility members of an Integrated Product Team (IPT) during concept design. Our focus is on the execution of the what we call the “chain method”, which illustrates the structure of function delivery in a concept in a simple pictorial way and helps the IPT to understand the advantages or disadvantages of using a modular or an integral product architecture. The producibility members play a central role in capturing and evaluating the chains for different candidate concepts and decompositions.
Technical Paper

Characterization of Structural, Volume and Pressure Components to Space Suit Joint Rigidity

2009-07-12
2009-01-2535
Gas-pressurized space suits are highly resistive to astronaut movement, and this resistance has been previously explained by volume and/or structural effects. This study proposed that an additional effect, pressure effects due to compressing/expanding the internal gas during joint articulation, also inhibits mobility. EMU elbow torque components were quantified through hypobaric testing. Structural effects dominated at low joint angles, and volume effects were found to be the primary torque component at higher angles. Pressure effects were found to be significant only at high joint angles (increased flexion), contributing up to 8.8% of the total torque. These effects are predicted to increase for larger, multi-axis joints. An active regulator system was developed to mitigate pressure effects, and was found to be capable of mitigating repeated pressure spikes caused by volume changes.
Technical Paper

Columbus ECLS Activation and Initial Operations

2008-06-29
2008-01-2135
European Space Agency's (ESA's) Columbus module was launched on February 7, 2008. This marks the completion of more than 10 years of development. It is a major step forward for Europe in the area of Environmental Control and Life Support (ECLS) as Columbus contains several major assemblies which have been developed in Europe. These include the Condensing Heat Exchanger, Condensate Water Separator and the Cabin Fans. The paper gives a short overview of the system and its features and it will report the experiences from the initial activation and operations phase.
Technical Paper

Cost Awareness in Design: The Role of Data Commonality

1996-02-01
960008
Enhanced information management techniques made available through emerging Information Technology platforms hold a promise of providing significant improvements in both the effectiveness and efficiency of developing complex products. Determining actual management implementations that deliver on this promise has often proven elusive. Work in conjunction with the Lean Aircraft Initiative at MIT has revealed a straight forward use of Information Technology that portends significant cost reductions. By integrating previously separate types of data involved in the process of product development, engineers and designers can make decisions that will significantly reduce ultimate costs. Since the results presented are not specific to particular technologies or manufacturing processes, the conclusions are broadly applicable.
Journal Article

Design Drivers of Energy-Efficient Transport Aircraft

2011-10-18
2011-01-2495
The fuel energy consumption of subsonic air transportation is examined. The focus is on identification and quantification of fundamental engineering design tradeoffs which drive the design of subsonic tube and wing transport aircraft. The sensitivities of energy efficiency to recent and forecast technology developments are also examined.
Technical Paper

Development of Columbus Orbital Facility Thermal Mathematical Models for Integrated International Space Station Thermal Analyses

1996-07-01
961540
The Columbus Orbital Facility is being developed as the European laboratory contribution to the United States' led International Space Station programme. The need to exchange thermal mathematical models frequently amongst the Space Station partners for thermal analyses in support of their individual programme milestone, integration and verification activities requires the development of a commonly agreed and effective approach to identify and validate mathematical models and environments. The approach needs to take into account the fact that the partners have different model and software tool requirements and the fact that the models need to be properly tailored to include all the relevant design features. It must also decouple both programmes from the unavoidable design changes they are still undergoing. This problem presents itself for both active and passive thermal interfaces.
Technical Paper

Development of a Time and Space Resolved Sampling Probe Diagnostic for Engine Exhaust Hydrocarbons

1996-02-01
961002
In order to understand how unburned hydrocarbons emerge from SI engines and, in particular, how non-fuel hydrocarbons are formed and oxidized, a new gas sampling technique has been developed. A sampling unit, based on a combination of techniques used in the Fast Flame Ionization Detector (FFID) and wall-mounted sampling valves, was designed and built to capture a sample of exhaust gas during a specific period of the exhaust process and from a specific location within the exhaust port. The sampling unit consists of a transfer tube with one end in the exhaust port and the other connected to a three-way valve that leads, on one side, to a FFID and, on the other, to a vacuum chamber with a high-speed solenoid valve. Exhaust gas, drawn by the pressure drop into the vacuum chamber, impinges on the face of the solenoid valve and flows radially outward.
Technical Paper

ECLSS Study for a European SpaceHaven

2005-07-11
2005-01-2808
The forthcoming planetary missions require an autonomous crew habitation and a high mass of metabolic consumables. To minimise the launch mass and/or the logistic needs, these missions shall then be based on regenerative technologies able to obtain resources for the human life from the on board produced wastes, guaranteeing a high closure degree of the system. In this context ESA has promoted a preliminary study called SpaceHaven, to understand which functions must be guaranteed for a long term and autonomous mission and to investigate about the hardware/technologies to be exploited to meet the identified functions. A dedicated demonstration program is to be proposed when needed technologies are neither available in Europe nor currently covered by a dedicated technological development.
Technical Paper

ECS Re-Test Analytical Evaluation

2005-07-11
2005-01-3118
A final test activity was carried out to complete the verification of the Environmental Control System (ECS) performances by experimentally reproducing the thermal hydraulic behaviour of the Environmental Control & Life Support Subsystem (ECLSS) section integrated in the overall Module, expected on analytical basis. A previous test campaign (called Columbus ECS PFM Test) carried out in EADS-Bremen in spring 2003 and described in paper number 2004-01-2425 showed some contradictory data concerning the air loop behaviour. These incoherent test results were related to the environmental and geometrical cabin loop conditions during the on-ground 1g test and to improper position of the sensor measuring the cabin temperature. For this reason a partial repetition of the test has been performed. In particular, this experimental campaign was focused on the verification of the cabin air temperature control, as a consequence of the Temperature Control Valve (TCV) movement.
Technical Paper

Esarad--Improvements to the European Space AgencyS Radiative Analyses

1996-07-01
961374
ESARAD is an integrated suite of analysis tools for thermal radiative analysis. The suite provides modules for: • Geometry Definition; • Calculation of view factor, radiative exchange factor and solar, albedo and planet flux results; •Visualization of models in orbit with pre- and post-processing of radiative and thermal results; • Reporting of all aspects of the model; and • Generation of Input Files for Thermal Analysis tools. ESARAD is driven by a fully developed GUI, providing the user with a simple, intuitive windows, menus, forms interface to all its features. A modern, block structured language can also be used to run ESARAD. This gives the advanced user great power and flexibility to perform the most complex analyses. ESARAD was designed and developed between 1988 and 1991 to replace the VWHEAT software used by ESA at that time.
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