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51.
Gernot E. Groemer Michael Storrie-Lombardi Birgit Sattler Oliver Hauser Klaus Bickert Eva Hauth Stefan Hauth Ulrich Luger Daniel Schildhammer Daniel Foeger Jan Klauck 《Acta Astronautica》2011,68(1-2):218-225
As part of the “PolAres” research programme, we are investigating techniques to detect and reduce forward contamination of the Mars regolith during human exploration. We report here on the development of a spacesuit simulator-prototype dubbed “Aouda.X,” document the inability of current technology to produce a static charge sufficient to minimize dust transport on the suit, and present preliminary results employing laser induced fluorescence emission (L.I.F.E.) techniques to monitor fluorescent microspherules as biological contamination proxies. 相似文献
52.
Elliott Coleshill Layi Oshinowo Richard Rembala Bardia Bina Daniel Rey Shelley Sindelar 《Acta Astronautica》2009,64(9-10):869-874
The Special Purpose Dexterous Manipulator (SPDM), known as “Dextre”, is currently slated to launch in February 2008 for deployment on the International Space Station (ISS) as the final component of Canada's Mobile Servicing System (MSS). Dextre's primary role on the Space Station is to perform repair and replacement (R&R) maintenance tasks on robotically compatible hardware such as Orbital Replaceable Units (ORUs), thereby eventually easing the burden on the ISS crew.This burden on the on-orbit crew translates practically into crew time being a limited resource on the ISS, and as such, finding ways to assist the crew in performing their tasks or offloading the crew completely when appropriate is a bonus to the ISS program. This is already accomplished very effectively by commanding as many non-critical robotics tasks as possible, such as powering up and free-space maneuvering of the Space Station Remote Manipulator System (SSRMS), known as “Canadarm2”, from the Ground.Thus, beyond its primary role, and based on an increasing clarity regarding the challenges of external maintenance on the ISS, Dextre is being considered for use in a number of ways with the objective of improving ISS operations while reducing and optimizing the use of crew time through the use of ground control for various tasks, pre-positioning hardware, acting as a temporary storage platform to break an Extra Vehicular Activity (EVA) day into manageable timelines, and extending the physical reach and range of the Canadarm2.This paper discusses the planned activities and operations for Dextre an rationale for how these will help optimize the use of crew resources on the ISS. 相似文献
53.
Daniel J. Semick 《Space Policy》1987,3(4):343-344
A panel session on ‘Creative approaches to commercial joint ventures in space’ took place at the American Society of Public Administration National Conference, 28 March 1 April 1987. This report highlights the comments made by the panelists1 on the steps NASA and US industry can take together to ensure US space leadership. 相似文献
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55.
Daniel Gómez Luis N. Martín Pablo Dmitruk 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2013
Because of its proximity, our Sun provides a unique opportunity to perform high resolution observations of its outer layers throughout the whole electromagnetic spectrum. We can also theoretically model most of the fascinating physical phenomena taking place on the Sun, as well as their impact on the solar system. 相似文献
56.
Validity and Sensitivity of a Brief Psychomotor Vigilance Test (PVT-B) to Total and Partial Sleep Deprivation 总被引:2,自引:0,他引:2
The Psychomotor Vigilance Test (PVT) objectively assesses fatigue-related changes in alertness associated with sleep loss, extended wakefulness, circadian misalignment, and time on task. The standard 10-min PVT is often considered impractical in applied contexts. To address this limitation, we developed a modified brief 3-min version of the PVT (PVT-B). The PVT-B was validated in controlled laboratory studies with 74 healthy subjects (34 female, aged 22-45 years) that participated either in a total sleep deprivation (TSD) study involving 33 hours awake (N=31 subjects) or in a partial sleep deprivation (PSD) protocol involving 5 consecutive nights of 4 hours time in bed (N=43 subjects). PVT and PVT-B were performed regularly during wakefulness. Effect sizes of 5 key PVT outcomes were larger for TSD than PSD and larger for PVT than for PVT-B for all outcomes. Effect size was largest for response speed (reciprocal response time) for both the PVT-B and the PVT in both TSD and PSD. According to Cohen's criteria, effect sizes for the PVT-B were still large (TSD) or medium to large (PSD, except for fastest 10% RT). Compared to the 70% decrease in test duration the 22.7% (range 6.9%-67.8%) average decrease in effect size was deemed an acceptable trade-off between duration and sensitivity. Overall, PVT-B performance had faster response times, more false starts and fewer lapses than PVT performance (all p<0.01). After reducing the lapse threshold from 500 ms to 355 ms for PVT-B, mixed model ANOVAs indicated no differential sensitivity to sleep loss between PVT-B and PVT for all outcome variables (all P>0.15) but the fastest 10% response times during PSD (P<0.001), and effect sizes increased from 1.38 to 1.49 (TSD) and 0.65 to 0.76 (PSD), respectively. In conclusion, PVT-B tracked standard 10-min PVT performance throughout both TSD and PSD, and yielded medium to large effect sizes. PVT-B may be a useful tool for assessing behavioral alertness in settings where the duration of the 10-min PVT is considered impractical, although further validation in applied settings is needed. 相似文献
57.
InSight Mars Lander Robotics Instrument Deployment System 总被引:1,自引:0,他引:1
A. Trebi-Ollennu Won Kim Khaled Ali Omair Khan Cristina Sorice Philip Bailey Jeffrey Umland Robert Bonitz Constance Ciarleglio Jennifer Knight Nicolas Haddad Kerry Klein Scott Nowak Daniel Klein Nicholas Onufer Kenneth Glazebrook Brad Kobeissi Enrique Baez Felix Sarkissian Menooa Badalian Hallie Abarca Robert G. Deen Jeng Yen Steven Myint Justin Maki Ali Pourangi Jonathan Grinblat Brian Bone Noah Warner Jaime Singer Joan Ervin Justin Lin 《Space Science Reviews》2018,214(5):93
The InSight Mars Lander is equipped with an Instrument Deployment System (IDS) and science payload with accompanying auxiliary peripherals mounted on the Lander. The InSight science payload includes a seismometer (SEIS) and Wind and Thermal Shield (WTS), heat flow probe (Heat Flow and Physical Properties Package, HP3) and a precision tracking system (RISE) to measure the size and state of the core, mantle and crust of Mars. The InSight flight system is a close copy of the Mars Phoenix Lander and comprises a Lander, cruise stage, heatshield and backshell. The IDS comprises an Instrument Deployment Arm (IDA), scoop, five finger “claw” grapple, motor controller, arm-mounted Instrument Deployment Camera (IDC), lander-mounted Instrument Context Camera (ICC), and control software. IDS is responsible for the first precision robotic instrument placement and release of SEIS and HP3 on a planetary surface that will enable scientists to perform the first comprehensive surface-based geophysical investigation of Mars’ interior structure. This paper describes the design and operations of the Instrument Deployment Systems (IDS), a critical subsystem of the InSight Mars Lander necessary to achieve the primary scientific goals of the mission including robotic arm geology and physical properties (soil mechanics) investigations at the Landing site. In addition, we present test results of flight IDS Verification and Validation activities including thermal characterization and InSight 2017 Assembly, Test, and Launch Operations (ATLO), Deployment Scenario Test at Lockheed Martin, Denver, where all the flight payloads were successfully deployed with a balloon gravity offload fixture to compensate for Mars to Earth gravity. 相似文献
58.
Anthony R. Yeates Tahar Amari Ioannis Contopoulos Xueshang Feng Duncan H. Mackay Zoran Mikić Thomas Wiegelmann Joseph Hutton Christopher A. Lowder Huw Morgan Gordon Petrie Laurel A. Rachmeler Lisa A. Upton Aurelien Canou Pierre Chopin Cooper Downs Miloslav Druckmüller Jon A. Linker Daniel B. Seaton Tibor Török 《Space Science Reviews》2018,214(5):99
Seven different models are applied to the same problem of simulating the Sun’s coronal magnetic field during the solar eclipse on 2015 March 20. All of the models are non-potential, allowing for free magnetic energy, but the associated electric currents are developed in significantly different ways. This is not a direct comparison of the coronal modelling techniques, in that the different models also use different photospheric boundary conditions, reflecting the range of approaches currently used in the community. Despite the significant differences, the results show broad agreement in the overall magnetic topology. Among those models with significant volume currents in much of the corona, there is general agreement that the ratio of total to potential magnetic energy should be approximately 1.4. However, there are significant differences in the electric current distributions; while static extrapolations are best able to reproduce active regions, they are unable to recover sheared magnetic fields in filament channels using currently available vector magnetogram data. By contrast, time-evolving simulations can recover the filament channel fields at the expense of not matching the observed vector magnetic fields within active regions. We suggest that, at present, the best approach may be a hybrid model using static extrapolations but with additional energization informed by simplified evolution models. This is demonstrated by one of the models. 相似文献
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60.
Bus-DeMeo光谱分类系统中有24种小行星光谱类型以及约27种陨石矿物学类型。小行星和陨石之间的光谱联系在质量和可靠性上差异很大原因主要是某些矿物学中缺乏诊断特征和空间风化作用。将回顾从可见光和近红外光谱中远程获取的小行星矿物学信息,讨论如何从地质学家的角度理解小行星的光谱辨识。 相似文献