Electric Propulsion Technologies Comparative Analysis: Application to Current and Future Space Missions

Author(s):  
J. GONZALEZ ◽  
G. SACCOCCIA
Author(s):  
Carsten Arthur Scharlemann ◽  
Martin Tajmar

The increasing application of micro-satellites (from 10 kg up to 100 kg) for a rising number of various missions demands the development of new miniaturized propulsion systems. Micro-satellites have special requirements for the propulsion system such as small mass, reduced volume, and very stringent electrical power constraints. Existing propulsion systems often can not satisfy these requirements. The Space Propulsion Department of the ARC Seibersdorf research dedicated itself to the development and test of various micropropulsion systems for present and future space missions. The portfolio of the systems under development includes electrical and chemical propulsion systems. The covered thrust and specific impulse of the developed propulsion systems ranges from 1μN to 1N and 500 s to 8000 s respectively. Based on the large experience obtained over several decades in the development of Field Emission Electric Propulsion systems (FEEP), several microstructured FEEPs have been developed. The design of these systems is presented as well as preliminary test results and a summarization of the experience obtained during the process of miniaturizing such systems. The development of miniaturized chemical propulsion systems includes a bipropellant and a monopropellant thruster. The bipropellant thruster constitutes the smallest existing 1N thruster utilizing hydrogen peroxide. The thruster system consists of two micopumps for the propellant feed and a microturbine to generate the power for operating the pumps. The monopropellant thruster is a derivative of the bipropellant thruster. It offers a lower specific impulse than the bipropellant system but due to its reduced system complexity it represents also a promising candidate for several future space missions. Both systems utilize rocket grade hydrogen peroxide (green propellant), which is decomposed with the help of an advanced monolithic catalyst. The present paper discusses the design methods and the physical limitations of such chemical propulsion systems with regard to their miniaturization and summarizes their performance evaluation.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Jochen Hinkelbein ◽  
Anton Ahlbäck ◽  
Christine Antwerber ◽  
Lisa Dauth ◽  
James DuCanto ◽  
...  

AbstractIn the next few years, the number of long-term space missions will significantly increase. Providing safe concepts for emergencies including airway management will be a highly challenging task. The aim of the present trial is to compare different airway management devices in simulated microgravity using a free-floating underwater scenario. Five different devices for airway management [laryngeal mask (LM), laryngeal tube (LT), I-GEL, direct laryngoscopy (DL), and video laryngoscopy (VL)] were compared by n = 20 paramedics holding a diving certificate in a randomized cross-over setting both under free-floating conditions in a submerged setting (pool, microgravity) and on ground (normogravity). The primary endpoint was the successful placement of the airway device. The secondary endpoints were the number of attempts and the time to ventilation. A total of 20 paramedics (3 female, 17 male) participated in this study. Success rate was highest for LM and LT and was 100% both during simulated microgravity and normogravity followed by the I-GEL (90% during microgravity and 95% during normogravity). However, the success rate was less for both DL (60% vs. 95%) and VL (20% vs. 60%). Fastest ventilation was performed with the LT both in normogravity (13.7 ± 5.3 s; n = 20) and microgravity (19.5 ± 6.1 s; n = 20). For the comparison of normogravity and microgravity, time to ventilation was shorter for all devices on the ground (normogravity) as compared underwater (microgravity). In the present study, airway management with supraglottic airways and laryngoscopy was shown to be feasible. Concerning the success rate and time to ventilation, the optimum were supraglottic airways (LT, LM, I-GEL) as their placement was faster and associated with a higher success rate. For future space missions, the use of supraglottic airways for airway management seems to be more promising as compared to tracheal intubation by DL or VL.


Cryogenics ◽  
2010 ◽  
Vol 50 (9) ◽  
pp. 597-602 ◽  
Author(s):  
Keisuke Shinozaki ◽  
Kazuhisa Mitsuda ◽  
Noriko Y. Yamasaki ◽  
Yoh Takei ◽  
Kensuke Masui ◽  
...  
Keyword(s):  

Author(s):  
Keisuke SHINOZAKI ◽  
Takehiro NOHARA ◽  
Makiko ANDO ◽  
Atsushi OKAMOTO ◽  
Masakatsu MAEDA ◽  
...  

Author(s):  
Aggelos Liapis ◽  
Evangelos Argyzoudis

The Concurrent Design Facility (CDF) of the European Space Agency (ESA) allows a team of experts from several disciplines to apply concurrent engineering for the design of future space missions. It facilitates faster and effective interaction of all disciplines involved, ensuring consistent and high-quality results. It is primarily used to assess the technical and financial feasibility of future space missions and new spacecraft concepts, though for some projects, the facilities and the data exchange model are used during later phases. This chapter focuses on the field of computer supported collaborative work (CSCW) and its supporting areas whose mission is to support interaction between people, using computers as the enabling technology. Its aim is to present the design and implementation framework of a semantically driven, collaborative working environment (CWE) that allows ESA’s CDF to be used by projects more extensively and effectively during project meetings, task forces, and reviews.


Author(s):  
David A. Rothery

Regular satellites of the giant planets have been described as ‘worlds in their own right’. ‘Regular satellites in close up’ describes the fascinating physical features and chemistry of Jupiter’s ‘Galilean moons’—Io, Europa, Ganymede, and Callisto—before considering Saturn’s moons, Titan, Enceladus, and Iapetus, as well as Miranda and Ariel, the moons of Uranus, and Triton, a moon of Neptune. These moons have very distinct characteristics and some are widely regarded as better candidates than Mars for hosting extraterrestrial life. It concludes with a look towards future space missions to observe and examine these distant moons.


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