Software-implemented fault detection for high-performance space applications

AbstractDesigning on-board computers (OBC) for future space missions is determined by the trade-off between reliability and performance. Space applications with higher computational demands are not supported by currently available, state-of-the-art, space-qualified computing hardware, since their requirements exceed the capabilities of these components. Such space applications include Earth observation with high-resolution cameras, on-orbit real-time servicing, as well as autonomous spacecraft and rover missions on distant celestial bodies. An alternative to state-of-the-art space-qualified computing hardware is the use of commercial-off-the-shelf (COTS) components for the OBC. Not only are these components cheap and widely available, but they also achieve high performance. Unfortunately, they are also significantly more vulnerable to errors induced by radiation than space-qualified components. The ScOSA (Scalable On-board Computing for Space Avionics) Flight Experiment project aims to develop an OBC architecture which avoids this trade-off by combining space-qualified radiation-hardened components (the reliable computing nodes, RCNs) together with COTS components (the high performance nodes, HPNs) into a single distributed system. To abstract this heterogeneous architecture for the application developers, we are developing a middleware for the aforementioned OBC architecture. Besides providing an monolithic abstraction of the distributed system, the middleware shall also enhance the architecture by providing additional reliability and fault tolerance. In this paper, we present the individual components comprising the middleware, alongside the features the middleware offers. Since the ScOSA Flight Experiment project is a successor of the OBC-NG and the ScOSA projects, its middleware is also a further development of the existing middleware. Therefore, we will present and discuss our contributions and plans for enhancement of the middleware in the course of the current project. Finally, we will present first results for the scalability of the middleware, which we obtained by conducting software-in-the-loop experiments of different sized scenarios.

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Towards Continuous Production of Shaped Honeycombs

Volume 3: Manufacturing Equipment and Systems ◽

10.1115/msec2018-6646 ◽

2018 ◽

Author(s):

Sam E. Calisch ◽

Neil A. Gershenfeld

Keyword(s):

High Performance ◽

Continuous Production ◽

Continuous Process ◽

Three Dimensional ◽

Sandwich Panels ◽

Performance Space ◽

Bending Loads ◽

Future Work ◽

The Impact ◽

Parallel Folding

Honeycomb sandwich panels are widely used for high performance parts subject to bending loads, but their manufacturing costs remain high. In particular, for parts with non-flat, non-uniform geometry, honeycombs must be machined or thermoformed with great care and expense. The ability to produce shaped honeycombs would allow sandwich panels to replace monolithic parts in a number of high performance, space-constrained applications, while also providing new areas of research for structural optimization, distributed sensing and actuation, and on-site production of infrastructure. Previous work has shown methods of directly producing shaped honeycombs by cutting and folding flat sheets of material. This research extends these methods by demonstrating work towards a continuous process for the cutting and folding steps of this process. An algorithm for producing a manufacturable cut-and-fold pattern from a three-dimensional volume is designed, and a machine for automatically performing the required cutting and parallel folding is proposed and prototyped. The accuracy of the creases placed by this machine is characterized and the impact of creasing order is demonstrated. Finally, a prototype part is produced and future work is sketched towards full process automation.

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Evaluation of high-performance space nuclear electric generators for electric propulsion application

10.1063/1.1449780 ◽

2002 ◽

Cited By ~ 2

Author(s):

Gordon Woodcock

Keyword(s):

Electric Propulsion ◽

High Performance ◽

Performance Space ◽

Electric Generators

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Efficient Space-Time Two Dimensional RAKE Receiver in Asynchronous Cooperative Communications Systems with Full Diversity

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.536-537.719 ◽

2014 ◽

Vol 536-537 ◽

pp. 719-725

Author(s):

Dong Wu Li ◽

Chang Xing Pei ◽

Yun Liang Meng

Keyword(s):

Cooperative Communication ◽

Communication System ◽

Cooperative Communications ◽

High Performance ◽

Rake Receiver ◽

Space Time ◽

Two Dimensional ◽

Combination Rules ◽

Performance Space ◽

Full Diversity

A high-performance space-time two dimensional RAKE receiving algorithm was proposed in asynchronous cooperative communication system. the transmitting signals were estimated coarsely by traditional space-time rake receiver, then on the basis of that we introduce feedback technology, each multipath signal of transmitted signals was composed by the decision results, and then every multipath component in the received signal can be obtained by eliminating the composed multipath signals from the received signal. Finally, the multipath components were combined by space-time combination and multipath combination rules accordingly, so spatial as well as multipath diversities were achieved. Simulation results show that the new scheme can reduce the bit error rate dramatically compare with traditional space-time RAKE in asynchronous cooperative communication system.

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Main results of the DAMPE space detector after 4 years in orbit

International Journal of Modern Physics A ◽

10.1142/s0217751x20440248 ◽

2020 ◽

Vol 35 (36) ◽

pp. 2044024

Author(s):

Piergiorgio Fusco

Keyword(s):

Gamma Rays ◽

High Performance ◽

Angular Resolution ◽

Dark Matter Particle ◽

Electromagnetic Calorimeter ◽

Performance Space ◽

Scientific Institutions ◽

Chinese Academy Of Sciences ◽

And Performance ◽

Academy Of Sciences

The DArk Matter Particle Explorer (DAMPE) is a high-performance space particle detector launched in orbit in 2015 by a collaboration of Chinese, Italian and Swiss scientific institutions, coordinated by the Chinese Academy of Sciences. It consists of a high-resolution segmented BGO electromagnetic calorimeter with a depth of 32 radiation lengths, a silicon-tungsten tracker-converter with an angular resolution below [Formula: see text], an anti-coincidence shield and ion detector, and a neutron detector. The detector characteristics and performance, and the latest observations of cosmic electrons up to 5 TeV, protons and nuclei up to 100 TeV and gamma-rays up to 10 TeV are presented.

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Fused Filament Fabrication of PEEK: A Review of Process-Structure-Property Relationships

Polymers ◽

10.3390/polym12081665 ◽

2020 ◽

Vol 12 (8) ◽

pp. 1665 ◽

Cited By ~ 2

Author(s):

Ali Reza Zanjanijam ◽

Ian Major ◽

John G. Lyons ◽

Ugo Lafont ◽

Declan M. Devine

Keyword(s):

High Performance ◽

Space Station ◽

Weight Ratio ◽

High Strength ◽

Structure Property ◽

Fused Filament Fabrication ◽

Space Applications ◽

Structure Property Relationships ◽

Complex Design ◽

Process Structure

Poly (ether ether ketone) (PEEK) is a high-performance engineering thermoplastic polymer with potential for use in a variety of metal replacement applications due to its high strength to weight ratio. This combination of properties makes it an ideal material for use in the production of bespoke replacement parts for out-of-earth manufacturing purposes, in particular on the International Space Station (ISS). Additive manufacturing (AM) may be employed for the production of these parts, as it has enabled new fabrication pathways for articles with complex design considerations. However, AM of PEEK via fused filament fabrication (FFF) encounters significant challenges, mostly stemming from the semi crystalline nature of PEEK and its associated high melting temperature. This makes PEEK highly susceptible to changes in processing conditions which leads to a large reported variation in the literature on the final performance of PEEK. This has limited the adaption of FFF printing of PEEK in space applications where quality assurance and reproducibility are paramount. In recent years, several research studies have examined the effect of printing parameters on the performance of the 3D-printed PEEK parts. The aim of the current review is to provide comprehensive information in relation to the process-structure-property relationships in FFF 3D-printing of PEEK to provide a clear baseline to the research community and assesses its potential for space applications, including out-of-earth manufacturing.

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The Effect of Oxygen Plasma on Some Experimental Polymers Containing Silicon and Phosphorus

Journal of Fire Sciences ◽

10.1177/073490419301100203 ◽

1993 ◽

Vol 11 (2) ◽

pp. 137-146 ◽

Cited By ~ 11

Author(s):

J.W. Connell ◽

J.G. Smith ◽

P.M. Hergenrother

Keyword(s):

Weight Loss ◽

High Performance ◽

Atomic Oxygen ◽

Oxygen Plasma ◽

Weight Retention ◽

Flame Resistance ◽

Space Applications ◽

Thermosetting Resins ◽

Limiting Oxygen Index ◽

Arylene Ether

As part of a NASA program on high performance polymers for space applications, polymers containing silicon and phosphorus were prepared, characterized and exposed to an oxygen plasma under vacuum. Thin films of polyimides containing pendent siloxane groups, thermosetting resins contain ing silicon and poly(arylene ether)s containing phenylphosphine oxide were ex posed to a radio frequency generated oxygen plasma to assess their stability. The weight loss of the films was monitored as a function of exposure time and compared with that of Ultem® and Kapton® polyimide films of the same thick ness exposed under identical conditions. All of the experimental materials ex hibited better weight retention than either of the commercial polyimides. The thermosetting resins containing silicon and poly(arylene ether)s containing phosphine oxide exhibited only minor weight loss (0-5%) compared to that ex hibited by Ultem® (75-100%) and Kapton® (35-82%). Organic polymers con taining silicon are known to form silicates and silicon dioxide when exposed to atomic oxygen providing an in situ protective coating. Likewise, polymers con taining phosphorus have been shown to form an inorganic phosphate surface layer which subsequently provides protection from further oxidation. The same inherent characteristics that provide the polymers with atomic oxygen resis tance (i.e., high oxidation state or inorganic oxide formation) may also impart fire resistance. Materials containing phosphorus are known to exhibit good flame resistance. The chemistry, properties, limiting oxygen index and oxygen plasma resistance of these materials will be discussed.

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