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Several research programs which have applied thermal scale modeling to a radiation-conduction heat transfer system (unmanned spacecraft) and to a radiation-conduction-convection heat transfer system (manned spacecraft) are reviewed and evaluated. ...The utilization of scaled models in the development of spacecraft thermal control systems is discussed. The criteria necessary to establish thermal similitude are developed as well as techniques for designing scaled thermal models.

How much integrated system level test should be performed on a spacecraft before it is launched? Although sometimes system test is minimized, experience shows that systems level testing should be thorough and complete. ...Human-rated spacecraft test planning is informal, subjective, and inconsistent, and its extent is often determined by the decision maker's risk tolerance, decision-making style, and long-term or short-term view.

Using the presently available technologies in the fiber composite rotors and in magnetic bearings, it is feasible to design the flywheel energy storage to replace the battery in the spacecraft power system. The potential benefits are reductions in weight, size and cost. The fundamental design considerations in designing the photovoltaic/flywheel power system are investigated in this paper.

This paper describes the methods used by NASA for finding the “best” design approach for meeting the objectives of space exploration. Models of the design process and the role that cost analysis plays in the process will be described. The state-of-the-art of cost estimating will be discussed and a cost model designed for the exploration initiative will be presented. The Space Exploration Initiative will be discussed and a cost estimate presented.

Stochastic method is being used in several domains for design optimisation, but its application to spacecraft thermal control design is not yet consolidated. The paper presents an assessment of this technique applied to spacecraft thermal control design, made by Blue Engineering and Alenia Spazio under ESA contract, with the objective to assess the applicability of the method, the requirements for its implementation, the effects on the design process. ...The paper presents an assessment of this technique applied to spacecraft thermal control design, made by Blue Engineering and Alenia Spazio under ESA contract, with the objective to assess the applicability of the method, the requirements for its implementation, the effects on the design process.

The thermal design of a spacecraft is a time consuming and tedious process. As more graphical tools are becoming available, this process is becoming more efficient, and changes to the thermal design are more quickly implemented. ...This paper discusses the THERMICA-SINDA/G software system, where the entire spacecraft thermal design process in integrated in one interactive graphical environment.

This paper presents application of multi-objective optimization to the design of spacecraft power subsystem. The selection of optimum design can be achieved by having a comparative trade study among different alternatives available. ...The paper provides a methodology to optimize the SEPS (Spacecraft Electrical Power Subsystem) design process taking into account both the technology trades and initial sizing in a constrained environment. ...Then it presents spacecraft power system sizing, which is derived by the mission requirements and design constraints imposed by technology available.

Following the launch aboard a 7925 Delta II, and nearly three years of semi-dormant cruise mode, the NEAR spacecraft will rendezvous with and orbit the near-Earth asteroid 433 Eros. While orbiting 433 Eros, NEAR will conduct the first systematic scientific exploration of an asteroid by measuring its bulk, surface, and internal properties. ...In order to accomplish this task, the NEAR spacecraft contains a suite of sensors comprised of an Infrared (IR) Spectrometer, a Multispectral Imager/Spectrometer, an X-Ray/Gamma-Ray Spectrometer, a Magnetometer, and a Laser Rangefinder. ...The structure supporting these sensors is part of a 3-axis stabilized, solar-oriented spacecraft that employs fixed coplanar solar arrays to provide a constant voltage, regulated power bus.

The SPAS (Shuttle Pallet Satellite) is a battery powered, 3-axis stabilized spacecraft which provides mechanical interface, power, command, low rate telemetry and high density data storage.

This stage of the work was concluded by the flight experiment with a model analogue of the ammonia two-phase CHRS of the RS for the ISS in the transport spacecraft “Progress-242” as a part of the space station “Mir”. The article describes scientific and technical problems, which should be solved to promote this work.

Next, considering fundamental human inputs and outputs as baseline design drivers, shared clusters of spacecraft life support system (LSS) requirements were identified as a function of respective mission elements.

Many factors contribute to this including a lack of detailed physical characteristics of the spacecraft and knowledge of the distribution of the thermal loads within the spacecraft. Therefore, the thermal design typically reacts to the mechanical and electrical designs. ...Suppose analysis tools were available that would allow the thermal engineer to rapidly produce preliminary designs and weave the thermal design requirements such as thermal radiator size, preferred radiator location and heat load location into the overall spacecraft design. The result would be a more integrated spacecraft thermal design completed in less time using less of the spacecraft resources. ...Traditionally, the preliminary thermal design is behind the mechanical and electrical spacecraft design. Many factors contribute to this including a lack of detailed physical characteristics of the spacecraft and knowledge of the distribution of the thermal loads within the spacecraft.

Between 25 and 30 years ago, the IECEC proceedings carried a series of papers of the present authors and of other members of a JPL team on the problems and the desirable design features associated with the MHW RTGs to be used to power JPL’s Voyager I and II spacecraft. The Voyager I and II spacecraft have now successfully completed their original 12 year missions about 10 years ago, and are at distances of over 55 AU and 70 AU from the sun. ...The Voyager spacecraft seem to have several decades of life left to make more measurements outside of the solar system.

Although ST-5’s maximum eclipse is only 2 hours, future missions could involve eclipses as long as 8 hours. As spacecraft size, mass, and available resources decrease and eclipse duration increases, thermal engineers will be challenged to design simple but robust thermal control systems that meet temperature requirements for all phases of the mission. ...In addition, future similar missions may involve large “fleets” of such small spacecraft, which, for cost and I&T reasons, must be almost identical in design. Such spacecraft will require a generic but robust thermal control design that is suitable for a wide variety of thermal environments.

Techniques are established for controlling damage to spacecraft components. Short and long term goals are recommended to improve present design capability.

The near-Sun phase of the mission will enable the spacecraft to approach the Sun as close as 0.22 AU during part of its orbit, thereby permitting observations from a quasi heliosynchronous vantage point. ...The 3 axis stabilized spacecraft will carry two groups of scientific instruments: In-situ instruments to study the local environment and Remote Sensing instruments to observe the sun, therefore the latter will require apertures in the face oriented towards the Sun. ...All exposed items as antennae and solar arrays will be tailored to these conditions, and the spacecraft body will remain protected behind a sunshield, housing also the apertures of the Remote Sensing instruments.

The paucity of sensory inputs from the outside environment can be expected to pose challenges to crews on long-duration missions in the confines of spacecraft. A history of research and practice has demonstrated that sensory deprivation or exposure to confusing sensory inputs affect individuals, both in their performance of tasks and their well-being.

The unique environment of a manned spacecraft presents many technical and operational challenges when designing and developing cryogenic systems.

Measured temperatures for both the science payload and the spacecraft module and solar arrays are compared with those predicted by the correlated analytical model.

This paper discusses the findings for [Interior] Configuration Options, Habitability and Architectural Aspects of a first human spacecraft to Mars. In 2003 the space architecture office LIQUIFER was invited by the European Space Agency’s (ESA) AURORA program committee to consult the scientists and engineers from the European Space and Technology Center (ESTEC) and other European industrial communities with developing the first human mission to Mars, which will take place in 2030, regarding the architectural issues of crewed habitats. ...For 500 days before the 200-day journey back the spacecraft continues to circle the Martian orbit for further exploration. The entire mission program is based on our present knowledge of technology.