unmanned spacecraft
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Fibers ◽  
2021 ◽  
Vol 9 (10) ◽  
pp. 60
Author(s):  
Tomasz Blachowicz ◽  
Andrea Ehrmann

Cosmic radiation belongs to the challenges engineers have to deal with when further developing space travel. Besides the severe risks for humans due to high-energy particles or waves, the impact of cosmic radiation on electronics and diverse materials cannot be neglected, even in microsatellites or other unmanned spacecraft. Here, we explain the different particles or waves found in cosmic radiation and their potential impact on biological and inanimate matter. We give an overview of fiber-based shielding materials, mostly applied in the form of composites, and explain why these materials can help shielding spaceships or satellites from cosmic radiation.


Author(s):  
Vladimir S. KOVTUN ◽  
Aleksandr N. PAVLOV ◽  
Boris V. SOKOLOV ◽  
Dmitry A. PAVLOV ◽  
Valentin N. VOROTYAGIN

A key condition for accomplishing a mission of an unmanned spacecraft consists in providing it with resources. Resources can be replenished through synergetic observations of processes in cases where measured data are partially or fully missing or lacking for some of the controlled objects by means of measuring parameters of the processes characterizing the operation of other controlled objects. As an example, the paper discusses provisioning of resources for the process of controlling the motion about the center of mass by means of synergetic observations in cases where no inertial instrument was available for measuring the angular rate vector in the system controlling the motion of the geostationary communications satellite Yamal-200. Specifically, the observation is based on the operation of transitive closure of the binary relation defined on the base set of processes in the onboard systems and ground assets for radio interactions with the onboard systems of the unmanned spacecraft. Key words: unmanned spacecraft, control process, measuring data, binary relations, transitive closure, provision of resources.


Author(s):  
Vladimir S. KOVTUN ◽  
Aleksandr N. PAVLOV ◽  
Boris V. SOKOLOV ◽  
Dmitry A. PAVLOV ◽  
Valentin N. VOROTYAGIN

A key condition for accomplishing a mission of an unmanned spacecraft consists in providing it with resources. Resources can be replenished through synergetic observations of processes in cases where measured data are partially or fully missing or lacking for some of the controlled objects by means of measuring parameters of the processes characterizing the operation of other controlled objects. As an example, the paper discusses provisioning of resources for the process of controlling the motion about the center of mass by means of synergetic observations in cases where no inertial instrument was available for measuring the angular rate vector in the system controlling the motion of the geostationary communications satellite Yamal-200. Specifically, the observation is based on the operation of transitive closure of the binary relation defined on the base set of processes in the onboard systems and ground assets for radio interactions with the onboard systems of the unmanned spacecraft. Key words: unmanned spacecraft, control process, measuring data, binary relations, transitive closure, provision of resources.


Author(s):  
Aleksandr N. PAVLOV ◽  
Dmitry A. PAVLOV ◽  
Valentin N. VOROTYAGIN

Successful completion of a mission by an unmanned spacecraft (USC), both under nominal operational conditions both under examined contingencies and unexamined off-nominal situations is possible through designing survivability into the USC onboard system (OS). An analysis of current methods for evaluating USC OS survivability during their configuration management and reconfiguration under conditions of examined in-flight contingencies widely used in the design and development of the said USC has shown that these methods are not acceptable for evaluating the USC OS survivability in case of unexamined off-nominal situations in flight. This calls for development of conceptually novel methodological and procedural framework for evaluating structural survivability of USC OS configurations that take into account the level of participation of functional elements (FE) and OS subsystems in the USC control operations under various scenarios of the mission plan implementation. The paper proposes an original approach to evaluating the structural and technological survivability of the USC OS based on a fuzzy hypergraph formal representation of the operations to control the USC attitude, where the edges of the hypergraph connect the FE and OS subsystems that support the implementation of this or that specific control process. The paper also shows how one could use for the quantitative evaluation of the structural and technological survivability of a specific USC OS configuration the results of differentiation of a fuzzy hypergraph that could be visualized as a fuzzy hypergraph of technological independence of OS FE. Such an approach makes it possible to analyze the effects of FE on OS, identify the most critical elements, which have the lowest technological independence under mission plan implementation conditions, which could be used for providing a rationale for the required level of structural and functional redundancy of USC elements and subsystems introduced during various phases in its life cycle. Keywords: unmanned spacecraft, onboard systems survivability, fuzzy hypergraph derivative.


2017 ◽  
Vol 26 (1) ◽  
pp. 1-12 ◽  
Author(s):  
Martin Rees

Unmanned spacecraft have visited the other planets of our Solar System (and some of their moons), beaming back pictures of varied and distinctive worlds – but none propitious for life. However, prospects are far more interesting when we extend our gaze to other stars. Most stars are orbited by retinues of planets. Our home Galaxy contains a billion planets like the Earth. Do some of these have biospheres? Moreover, our Galaxy is one of billions visible with a large telescope – all the aftermath of a cosmic ‘big bang’ 13.8 billion years ago. More astonishing still, ‘our’ big bang may not have been the only one. The remarkable advances in recent decades are primarily owed to new engineering and technology. Armchair theory alone doesn’t get us far.


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