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A thermomechanical electronic multifunctional structure prototype has been modeled and optimized. The model focuses on the description of thermal and electrical phenomena, but leaves aside structural issues. It couples a three-dimensional thermal network with representations of different possible thermal control laws, namely on/off control, proportional logic, proportional-integral-derivative strategy, and the usage of positive temperature coefficient heaters. The parametric model was first validated and correlated through a comparison with simple physical solutions, and then with the actual results of a thermal vacuum test. Multiobjective optimization (based on genetic algorithms) has been used to define the best heater layout options, to identify the best control strategy in terms both of panel isothermia and energy consumption, and to fine-tune the parameters of the selected control strategy. The research reported in this paper has led to the definition of an optimal thermal control solution. An examination of the optimization results has shown that the simultaneous adjustment of the geometrical layout as well as the control strategy and its parameters can lead to energy savings of about 52%. [ABSTRACT FROM AUTHOR]

A long-duration microgravity environment has numerous detrimental effects on the human physiology. The most obvious solution for this problem related to long duration space exploration missions is to remedy the lack of gravity. This could be done using short arm human centrifuges but they do not seem to be sufficiently effective, perhaps because of the short duration exposure of this countermeasure and/or the huge body gravity gradient. New views have to be investigated, such as to see if a (very) long-arm rotating system generating a continuous 1 g or partial gravity field might resolve this issue. Besides the expected benefits regarding astronauts' microgravity pathologies, additionally the spacecraft itself, its on-board (sub-)systems and procedures might benefit from a rotating configuration. In this paper we address very briefly the medical issues, but the work is mainly focused on the advantages regarding engineering, operations, life support, safety and budget of having a constantly rotating spacecraft first in Low Earth Orbit and later for long duration missions to Mars. A large rotating spacecraft is feasible and affordable to build, operate and maintain. It has advantages for governmental and commercial use but also in light of the expected increase in space tourism. It will also save crew time and billions of dollars now being spent to counteract the effects of microgravity. A continuous rotating spacecraft providing Artificial Gravity will: • Improve crew health and wellbeing. • Improve mission safety and success. • Reduce costs significantly. • Simplify numerous operations in flight. • Provides the use of 1 g verified systems. [ABSTRACT FROM AUTHOR]