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Acta Astronautica
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Item-typ:Veröffentlichung, Communication quality affects performance of astronauts and support teams through increased workload: Insights from the AMADEE-20 analog Mars mission(Elsevier Science, 2023-05-18); ; ; Astronaut crews and ground control support teams are highly interdependent teams that need to communicate effectively to achieve a safe mission - despite being separated by large distances. Team communication quality with its facets clarity of objectives and information flow, is a key coordination process to achieve high team performance and task satisfaction. Especially in interdependent teams working in extreme environments with time-delayed communications, the team's success is threatened if communication is ineffective. In this study, we hypothesized that communication quality affects two key team outcomes, performance and task satisfaction, and that these effects can be explained by increases in workload (effort and frustration). Hypotheses were tested during the AMADEE-20 analog Mars mission hosted by the Austrian Space Forum. The analog astronauts (AA) were supported by an On-Site-Support (OSS) team and a remote Mission-Support-Centre (MSC) team. The MSC was the only contact line for both AA and OSS, and the communication between them had a one-way time delay of 10 min. Our study consisted of three runs in which members across the three different multiteam systems had to exchange information to solve an interdependent task. We measured communication quality, effort and frustration, task satisfaction, and team performance. Results show that clarity of objectives and information flow positively impacted multiteam system performance. Furthermore, clarity of objectives reduced experienced effort and this in turn enhances team performance. High levels of information flow reduced experienced frustration, which in turn enhanced task satisfaction. Our findings show that these facets of communication quality are essential for multiteam systems that work separated from each other by a distance. We stress that specific (team) communication training for astronauts and support personnel will be key to effective teamwork during future Mars missions, and thus to overall mission success.Wissenschaftlicher ArtikelBand:210421 104 - Some of the metrics are blocked by yourconsent settings
Item-typ:Veröffentlichung, System analysis of an ISRU production plant: Extraction of metals and oxygen from lunar regolithA study was conducted to compare the performance of three different ISRU production plants that extract metals and oxygen from regolith at the lunar South Pole. The processes selected were: (1) hydrogen reduction of ilmenite and carbonylation to produce low-carbon steels, (2) molten regolith electrolysis to produce ferrosilicon alloys, and (3) molten salt electrolysis, in particular the FFC-Cambridge process, together with vacuum distillation, to produce aluminum–silicon alloys. Holistic system sizing models, including excavation, beneficiation, handling, oxygen extraction and purification, metal processing, gas liquefaction and storage, thermal control, and power, were developed to determine the overall ISRU mass and power budgets. The most effective ISRU production plant preliminarily requires 6776 kg of hardware mass to produce 25 t/a of ferrosilicon alloys from Highlands regolith through molten regolith electrolysis. This facility coproduces 23.9 t/a of oxygen, presenting a total mass payback ratio of 0.14 kg of hardware/(kg of product/a). Sensitivity analyses are presented for the initial ilmenite and anorthite concentrations in regolith. The salt ratio (kg of molten salt per kg of regolith) of the FFC-Cambridge process and the degradation rate of the molten regolith electrolysis reactor are identified as key parameters that determine the feasibility of these ISRU processes. The mass and power of the production plants exhibit a slight economy of scale, indicating that larger amounts of metals and oxygen can be produced more efficiently.Wissenschaftlicher ArtikelBand:203238 199 - Some of the metrics are blocked by yourconsent settings
Item-typ:Veröffentlichung, Attitude determination & control system design for gravity recovery missions like GRACE(Elsevier, 2020-04-25); ; This paper is dedicated to the attitude control law synthesis for GRACE-like missions. Namely, two satellites move along the same orbit at a distance of several hundred kilometers and “look” at each other. This angular motion resembles the stabilization at unstable equilibrium position in the Orbital Frame. The reaction wheels cannot be used because they greatly affect the accelerometers measurements. Hence, only magnetorquers and thrusters may be utilized for the attitude control. Two different approaches are considered: linear quadratic regulator and Lyapunov-based controller. Control coefficients of the latter are obtained using the Floquet theory. Numerical simulation including atmospheric drag, solar radiation pressure and state vector measurements errors is carried out to validate suggested control techniques. The developed attitude determination and control system algorithms are tested for GRACE and GRACE-FO mission scenarios with relevant requirements and parameters.Wissenschaftlicher ArtikelBand:17347 28 - Some of the metrics are blocked by yourconsent settings
Item-typ:Veröffentlichung, The MaMBA-concept for an extraterrestrial base and its first module mock-upHabitats must enable astronauts to survive in an extraterrestrial environment, but the challenge is not only a technological one: architecture and engineering should be brought together to create an environment in which a crew can perform optimally. With missions to Mars in mind, crew mental health becomes a design driver equally important to the support of physiological functions. We here suggest a habitat concept, MaMBA (short for Moon and Mars Base Analog), which combines the two requirements. In its basic configuration, MaMBA consists of six upright cylindrical, hard-shell pressure vessels as main modules and two airlocks, which are all connected with inflatable corridor modules. We present the current state of the design and particularly focus on the laboratory module, of which we have constructed a mock-up equipped with scientific instrumentation. In the long-term, we plan to develop this laboratory module into a functional prototype including subsystems such as the life support system. Eventually, we aim to create a habitat which can serve as a test platform (for technologies, operations, and procedures) and whose usability is continually validated through iterative testing with human inhabitants. The habitat is open to international partners for simulations.Wissenschaftlicher Artikel184 279