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1.
《Acta Astronautica》2008,62(11-12):1043-1052
The paper concerns possible concept variants of a partially reusable Heavy-Lift Launch Vehicle derived from the advanced basic launcher (Ariane-2010) by means of substitution of the EAP Solid Rocket Boosters for a Reusable Starting Stage consisting two Liquid-propellant Reusable Fly-Back Boosters called “Bargouzin”.This paper describes the status of the presently studied RFBB concepts during its three phases.The first project phase was dedicated to feasibility expertise of liquid-rocket reusable fly-back boosters (“Baikal” type) utilization for heavy-lift space launch vehicle. The design features and main conclusions are presented.The second phase has been performed with the purpose of selection of preferable concept among the alternative ones for the future Ariane LV modernization by using RFBB instead of EAP Boosters. The main requirements, logic of work, possible configuration and conclusion are presented. Initial aerodynamic, ballistic, thermoloading, dynamic loading, trade-off and comparison analysis have been performed on these concepts.The third phase consists in performing a more detailed expertise of the chosen LV concept. This part summarizes some of the more detailed results related to flight performance, system mass, thermoprotection system, aspects of technologies, ground complex modification, comparison analyses and conclusion.  相似文献   

2.
This paper presents the study of a concept of Ariane-5 evolution by means of replacement of two solid-propellant boosters EAP with two liquid-propellant reusable fly-back boosters (RFBBs) called “Bargouzine”. The main design feature of the reference RFBB is LOX/LH2 propellant, the canard aerodynamic configuration with delta wings and rocket engines derived from Vulcain-2 identical to that of the central core except for the nozzle length. After separation RFBBs return back by use of air breathing engines mounted in the aft part and then landing on a runway.The aim of the study is a more detailed investigation of critical technology issues concerning reliability, re-usability and maintenance requirements. The study was performed in three main phases: system trade-off, technical consolidation, and programmatic synthesis. The system trade-off includes comparative analysis of two systems with three and four engines on each RFBB and determination of the necessary thrust level taking into account thrust reservation for emergency situations. Besides, this phase contains trade-off on booster aerodynamic configurations and abort scenario analysis.The second phase includes studying of controllability during the ascent phase and separation, thermo-mechanical design, development of ground interfaces and attachment means, and turbojets engine analysis taking into account reusability.  相似文献   

3.
In comparing the costs of different launch vehicles, the possibility of the risk of failure is assumed to be accounted for by the cost of insurance. The satellite may be insured against loss during launch, and the launch services provider may offer a “free relaunch.” However, actual costs of reliability and failure extend beyond this. Each failure necessitates an investigation and a “get well” programme by the operating agency, while putting the operations team “on hold” until services can resume. A commercial operator may also lose customer revenue and actual customers through loss of confidence or unavailability. Such costs tend to be hidden, and not evaluated in assessing the effectiveness of a system, but count towards total costs. Failure investigations help to improve system reliability, but this could equally have been achieved by expenditure in development and qualification. Reusable launch vehicles will have different costs associated with reliability and failure. The relationship between reliability and cost, properly assessed, ought to influence the design of both expendable and reusable launch systems.  相似文献   

4.
Investigations of blood pressure, heart rate (HR), and heart rate variability (HRV) during long term space flights on board the “ISS” have shown characteristic changes of autonomic cardiovascular control. Therefore, alterations of the autonomic nervous system occurring during spaceflight may be responsible for in- and post-flight disturbances. The device “Pneumocard” was developed to further investigate autonomic cardiovascular and respiratory function aboard the ISS. The hard-software diagnostic complex “Pneumocard” was used during in-flight experiment aboard ISS for autonomic function testing. ECG, photoplethysmography, respiration, transthoracic bioimpedance and seismocardiography were assessed in one male cosmonaut (flight lengths six month). Recordings were made prior to the flight, late during flight, and post-flight during spontaneous respiration and controlled respiration at different rates.HR remained stable during flight. The values were comparable to supine measurements on earth. Respiratory frequency and blood pressure decreased during flight. Post flight HR and BP values increased compared to in-flight data exceeding pre-flight values. Cardiac time intervals did not change dramatically during flight. Pulse wave transit time decreased during flight. The maximum of the first time derivative of the impedance cardiogram, which is highly correlated with stroke volume was not reduced in-flight.Our results demonstrate that autonomic function testing aboard the ISS using “Pneumocard” is feasible and generates data of good quality. Despite the decrease in BP, pulse wave transit time was found reduced in space as shown earlier. However, cardiac output did not decrease profoundly in the investigated cosmonaut.Autonomic testing during space flight detects individual changes in cardiovascular control and may add important information to standard medical control. The recent plans to support a flight to Mars, makes these kinds of observations all the more relevant and compelling.  相似文献   

5.
Present operational space telecommunication systems are based on simultaneous availability of more than one satellite on orbit, mainly a spare satellite in addition to the operational one.Considering the costs associated to the delivery of extra flight models and to extra launchers, the question is asked whether it would not be advantageous to launch a very limited number of “overredundant” spacecraft instead of several standard satellites.The paper gives main conditions of reliability, size and redundancy concept under which an “overredundant” spacecraft could be a competitive approach to future operational systems.  相似文献   

6.
The paper elaborates on “ lessons learned” from two recent ESA workshops, one focussing on the role of Innovation in the competitiveness of the space sector and the second on technology and engineering aspects conducive to better, faster and cheaper space programmes. The paper focuses primarily on four major aspects, namely:
1. a) the adaptations of industrial and public organisations to the global market needs;
2. b) the understanding of the bottleneck factors limiting competitiveness;
3. c) the trends toward new system architectures and new engineering and production methods;
4. d) the understanding of the role of new technology in the future applications.

Under the pressure of market forces and the influence of many global and regional players, applications of space systems and technology are becoming more and more competitive. It is well recognised that without major effort for innovation in industrial practices, organisations, R&D, marketing and financial approaches the European space sector will stagnate and loose its competence as well as its competitiveness. It is also recognised that a programme run according to the “better, faster, cheaper” philosophy relies on much closer integration of system design, development and verification, and draws heavily on a robust and comprehensive programme of technology development, which must run in parallel and off-line with respect to flight programmes.

A company's innovation capabilities will determine its future competitive advantage (in time, cost, performance or value) and overall growth potential. Innovation must be a process that can be counted on to provide repetitive, sustainable, long-term performance improvements. As such, it needs not depend on great breakthroughs in technology and concepts (which are accidental and rare). Rather, it could be based on bold evolution through the establishment of know-how, application of best practices, process effectiveness and high standards, performance measurement, and attention to customers and professional marketing. Having a technological lead allows industry to gain a competitive advantage in performance, cost and opportunities. Instrumental to better competitiveness is an R&D effort based on the adaptation of high technology products, capable of capturing new users, increasing production, decreasing the cost and delivery time and integrating high level of intelligence, information and autonomy. New systems will have to take in to account from the start what types of technologies are being developed or are already available in other areas outside space, and design their system accordingly. The future challenge for “faster, better, cheaper” appears to concern primarily “cost-effective”, performant autonomous spacecraft, “cost-effective”, reliable launching means and intelligent data fusion technologies and robust software serving mass- market real time services, distributed via EHF bands and Internet.

In conclusion, it can be noticed that in the past few years new approaches have considerably enlarged the ways in which space missions can be implemented. They are supported by true innovations in mission concepts, system architecture, development and technologies, in particular for the development of initiatives based on multi-mission mini-satellites platforms for communication and Earth observation missions. There are also definite limits to cost cutting (such as lowering heads counts and increasing efficiency), and therefore the strategic perspective must be shifted from the present emphasis on cost-driven enhancement to revenue-driven improvements for growth. And since the product life-cycle is continuously shortening, competitiveness is linked very strongly with the capability to generate new technology products which enhance cost/benefit performance.  相似文献   


7.
This paper presents the review of results of the navigating experiments which have been carried out during flight of microgravitational space platform (MSP) Foton-M2 in May–June 2005. The brief characteristic of the created MIRAGE–M equipment consisting from magnitometric system and satellite radionavigation receiver is given. The measurements have allowed to restore unguided MSP movement and to estimate a level of microaccelerations (microgravitations) onboard during flight, and have provided precision time-position binding of the research experiments. The data from the equipments transmitted on the telemetering channel have allowed testing the information technologies of virtual support of experiments in space. Flight testing of the equipment has allowed make a conclusion on usefulness of accommodation onboard the small-sized auxiliary navigating system focused for work with users of research experiments. The experiments on MSP Foton-M2 are the development of experiments with MIRAGE equipment carried out in 1999 during flight time of MSP Foton-12 [N.D. Semkin, V.V. Ivanov, V.I. Abrushkin, V.L. Balakin, I.V. Belokonov, K.E. Voronov, The experiments with magnetic fields formed by technical equipment inside Foton-12 spacecraft: the results of the MIRAGE experiments, in: Proceedings of International Conference “Scientific and Technological Experiments on Russian Foton/Bion Recoverable Satellites: Results, Problems and Outlooks”, 25–30 June 2000, pp. 116–122; V.L. Balakin, I.V. Belokonov, V.V. Ivanov, “Determination of motion of spacecraft Foton-12 as a result of magnetic fields measurement in MIRAGE experiment”, pp. 231–238 (published in the same place)].Paper is executed within the framework of the grant of the Russian Fund of Fundamental Researches 06-08-00244.  相似文献   

8.
GALILEO aims at involving Europe in a new generation of satellite navigation services. In the context of the phase A of this programme, many system options are still widely open: detailed requirements, constraints and hypotheses are not yet fully stabilised.In order to design a satellite constellation satisfying civil aviation and other users needs in this early stage of the system definition, it is necessary not only to take into account classical performance aspects, such as accuracy and availability of accuracy, but also cost constraints. The paper describes the design and dimensioning method which has led ALCATEL to propose a set of MEO constellations in the frame of the GALILEO project for ESA. It especially places emphasis upon the sensitivity of the system design to numerous parameters as well as its sensitivity to performance requirements.Potential candidate constellations obviously need to meet given performance specifications which are determined by operational aspects such as: satellite reliability, maintenance strategy (spare in orbit, launch on schedule, launch on need), deployment strategy (launcher choice, etc.). The estimated cost of a potential solution is mainly derived from the number of satellites and the deployment/maintenance strategy, but it is representative of the whole life-cycle of the constellation. Furthermore, the exhibited solution shall be “as robust as” possible to requirement or assumption changes. So, it should be a baseline solution that could be easily updated in order to take into account small upgrades.This has led to the performance of some trend analyses to understand the actual influence of some constraints or requirements on the system design, and to see how initial requirements can be efficiently relaxed in order to obtain the maximum system cost diminution for a minimum constraint relaxation. This will be very useful, if cost reduction is necessary, to quickly propose alternative or sub-solutions to the baseline one.  相似文献   

9.
Yuri V. Trifonov 《Acta Astronautica》1996,39(9-12):1021-1024
The preliminary estimations show that the contemporary level of electronic and information engineering makes it possible to create a small s/c of 150–200 kg mass capable to solve both the problems of Earth remote sensing and many other applied and scientific problems orbiting the planets at 500–1000 km. In accordance with the fundamental criterion for choosing parameters of small multipurpose spacecraft the small UNISAT s/c has been created on the basis of a unified space platform. The design provides for s/c energetic, thermal and space-saving parameters satisfying the conditions for accommodation of various-purpose payload and a possibility of using relatively inexpensive and light launchers like “Start-1” mobile launch complexes. Space platform mass is 100–120 kg; permissible payloads (PL) mass is 40–80 kg; maximal average power consumption of the payload is up to 60 W; three-axes orientation accuracy up to 0.001 deg./s; s/c lifetime is not less than 3–5 years.  相似文献   

10.
The new-born bioscience called Nanobiology has tackled the problems of the possibility of existence of extraterrestrial life and intelligence and of biosystem distribution in the Universe, as such questions actually belong to the realm of Theoretical Biology. The central, and yet unanswered points of such science have been reinvestigated by attempting knowledge and control of the hard-to-determine nanoscale-level classical and quantum interactions, which would supposedly give mechanistic, definite answers, both informationally and energetically, to the vexing questions put by biosystems to science: is the “living state” a physically definible concept, and how to define it? Are nanoscale kinetics or even detailed mechanics involved in the origin of life? What about intelligence, consciousness and their nanophysical roots? Are “life” and “intelligence” engineerable properties, or is any Artificial Intelligence program bound to mere metaphors? Self-organization, studied at the thermodynamic and the hydrodynamic level, showed the possibility of chemical evolution from amino acids, probably of cometary and/or meteoritic origin, up to spatiotemporal organization, autopoiesis and biological evolution, but didn't explain the origins of life. Questioning the uniqueness of the earthly evolutionary chemistry is cardinal for the ETI dilemma, as from a budgetary appraisal of perspectives in bionanoscale chaotic undecidable dynamics, quantum gravity and quantum vacuum, both “living state” and “intelligence” look like nonlocal, spacetime-linked cosmic phenomena.  相似文献   

11.
Space-based astrometry has a great tradition at ESA. The first space-based astrometric satellite in history, “Hipparcos”, was launched by ESA in 1989 and, in spite of orbital problems, was able to accomplish almost all of its tasks until it was finally shut down in 1993. The results of the Hipparcos mission were published by ESA in 1997 in the form of six CD-ROMs: the Hipparcos Catalogue contains 118,218 entries with median astrometric precision of around 1 milliarcsec, and specific results for double and multiple systems. In practice, Hipparcos drew for the first time the three-dimensional “map” of the spherical region of the Galaxy surrounding the Sun and having a radius of roughly 1,000 light years.

Then, in 1995, ESA launched the study of a new astrometric satellite, named “GAIA” and about a hundred times more powerful than Hipparcos, i.e. with median astrometric precision of around 10 microarcsec. This new satellite is intended to measure the parallaxes of over 50 million stars in the Galaxy, at least for the brightest stars, and this would mean to “draw” the three-dimensional map of the whole Galaxy, reaching out even to the Magellanic Clouds, 180,000 light years away.

The team of European scientists and engineers now designing GAIA, however, is facing hard technological difficulties. One of these is the design and coding of radically new and ultra-powerful mathematical algorithms for the on-board compression of the 50-million-stars data that GAIA will send to Earth from its intended geostationary orbit. Preliminary estimates of the raw data rates from the GAIA focal plane, in fact, are of the order of a few Gigabits per second. To reduce the data stream to the envisaged telemetry link of 1 Megabit per second, on-board data compression with a 1 to 1,000 ratio is the target. Clearly, this is far beyond the capabilities of any lossless compression technique (enabling compression ratios of 1 to some tens), and so some “wise” lossy compression mathematical procedure must be adopted.

In this paper a GAIA-adapted lossy data compression technique is presented, based on the Karhunen-Loève Transform (KLT). The essence of this method was already used by NASA for the Galileo mission when the large antenna got stuck and the mission was rescued by re-programming the on-board computer in terms of the KLT. That transform was officially named ICT — “Integer Cosine Transform” — by the NASA-JPL team led by Dr. Kahr-Ming Cheung. But the KLT here described for GAIA will of course differ from the JPL one in many regards, owing to the advances in computer technology.

Finally, estimates are also given about the possibility of using the KLT for onboard data compression in case GAIA is going to be put into orbit around the Lagrangian point L2 of the Earth-Sun system, and, above all, in case the number of stars to be observed is actually raised from 50 millions to one billion, as ESA currently appears to be likely to pursue.  相似文献   


12.
The literature on the history of spaceflight has depicted the early 1950s Colliers articles mostly as a forerunner to the peaceful and scientific exploration of space. Yet the centerpiece of Wernher von Braun's plan was a manned space station that would serve as reconnaissance platform and orbiting battle station for achieving “space superiority” over the USSR. One its roles could be the launching of nuclear missiles. When challenged as to the station's defensibility, von Braun even posited pre-emptive atomic strikes from space as a response to the development of a hostile anti-satellite capability.  相似文献   

13.
On going flights of Foton satellites allow to carry out research in the following domains: effect of space flight and outer space factors such as microgravity, artificial gravity and space radiation on physical processes and biological organisms. Experts from many Russian and foreign scientific institutions participated in the research. Over a period of time from 1973 to 1997 there were launched 11 BION satellites designed by the Central Specialized Design Bureau for carrying out fundamental and applied research in the field of space biology, medicine, radio physics and radiobiology with participation of specialists from the foreign countries.The goal of the present investigation was in developing a numerical simulator aimed at determining gas concentration and temperature fields established inside the scientific module of the spacecraft “Bion-M” and to perform optimization studies, which could meet strong requirements for air quality and temperature range allowable for operation of different biological experiments.  相似文献   

14.
The technical development trend of future launch vehicle systems is towards fully reusable systems, in order to reduce space transportation cost. However, different types of launch vehicles are feasible, as there are
• —winged two-stage systems (WTS)
• —ballistic single-stage vehicles (BSS)
• —ballistic two-stage vehicles (BTS)
The performance of those systems is compared according to the present state of the art as well as the development cost, based on the “TRANSCOST-Model”. The development costs are shown versus launch mass (GLOW) and pay-load for the three types of reusable systems mentioned above.It is shown that performance optimization and cost minimization lead to different results. It is more economic to increase the vehicle size for achieving higher performance, instead of increasing technical complexity.Finally it is described that due to the essentially lower launch cost of reusable vehicles it will be feasible to recover the development cost by an amortization charge on the launch cost. This possibility, however, would allow commercial funding of future launch vehicle developments.  相似文献   

15.
John C. Mankins   《Acta Astronautica》2009,65(9-10):1208-1215
Systems that depend upon the application of new technologies inevitably face three major challenges during development: performance, schedule and budget. Technology research and development (R&D) programs are typically advocated based on argument that these investments will substantially reduce the uncertainty in all three of these dimensions of project management. However, if early R&D is implemented poorly, then the new system developments that plan to employ the resulting advanced technologies will suffer from cost overruns, schedule delays and the steady erosion of initial performance objectives. It is often critical for senior management to be able to determine which of these two paths is more likely—and to respond accordingly. The challenge for system and technology managers is to be able to make clear, well-documented assessments of technology readiness and risks, and to do so at key points in the life cycle of the program.Several approaches have been used to evaluate technology maturity and risk in order to better anticipate later system development risks. The “technology readiness levels” (TRLs), developed by NASA, are one discipline-independent, programmatic figure of merit (FOM) that allows more effective assessment of, and communication regarding the maturity of new technologies. Another broadly used management tool is of the “risk matrix”, which depends upon a graphical representation of uncertainty and consequences. However, for the most part these various methodologies have had no explicit interrelationship.This paper will examine past uses of current methods to improve R&D outcomes and will highlight some of the limitations that can arise. In this context, a new concept for the integration of the TRL methodology, and the concept of the “risk matrix” will be described. The paper will conclude with observations concerning prospective future directions for the important new concept of integrated “technology readiness and risk assessments”.  相似文献   

16.
重复使用航天器具有快速、低成本的特性,是自由进出空间的重要技术途径之一。自从20世纪50年代重复使用航天器的概念被提出以来,历经70多年,重复使用航天器的研制取得了很大的进步,积累了丰富的经验和教训。基于国内外发展情况,梳理了重复使用航天器的技术路线,深入分析了其发展趋势,从设计、制造、试验、运行维护4个方面探讨了重复使用航天器的特点和难点,并提出了未来重复使用航天器发展的若干思考与建议。  相似文献   

17.
NASA, the initiator of the International Space Station (ISS), is currently reinforcing partnerships with the commercial sector as well as other ISS partner states in preparation for the ISS's operation and utilisation. This gives rise to an urgent need to analyse the ISS's legal framework in order to clearly state its legal merits and shortcomings. This essay presents the advantages and disadvantages of the ISS's legal framework by employing the “legalisation”-based approach. These advantages and disadvantages give us clues for selecting the optimal legal arrangement for the future development of the ISS programme. It will therefore be possible to minimise the risks associated with and to generate profits from ISS activities. This will ensure the effective and coherent implementation of the ISS programme.  相似文献   

18.
This first of several study papers, based on a fundamental paper presented in 1972, provides an independent conceptual analysis and evaluation of the lunar environment as industrial base and habitat. A selenosphere system strategy is outlined. The underlying concept is that of one or several lunar industrial zones for resource extraction and on-surface processing, integrated with a circumlunar zero-g processing capability, serving markets in geolunar space. A classification of lunar elements by utilization category is presented. Lunar oxygen is a prime candidate for being an initial economic “drawing card”, because of its value for fast transportation in geolunar space, requiring significantly fewer ships for equal transfer capability per unit time than electric transports which, however, have value, especially between geosynchronous and lunar orbit. The reduced development difficulties of controlled fusion outside the atmosphere and its advantages for extracting oxygen and other elements in quantity are summarized. Examples of lunar cycle management as fundamental exoindustrial requirement for economic resource enhancement are presented. The principal initial socio-economic value of lunar industry lies in the use of lunar resources for exoindustrial products and operations designed to accelerate, intensify and diversify Earth-related benefits. In the longer run, lunar settlements are a highly suitable proving ground for studying and testing the complex matrix of technological, biological, cultural, social and psychological aspects that must be understood and manageable before large settlements beyond Earth can have a realistic basis for viability. The lunar environment is more suitable for experimentation and comparatively more “forgiving” in case of failures than is orbital space.  相似文献   

19.
John D. Rummel   《Acta Astronautica》2009,64(11-12):1293-1297
“Special regions” on Mars are areas designated in the COSPAR planetary protection policy as areas that may support Earth microbes inadvertently introduced to Mars, or that may have a high probability of supporting indigenous martian life. Since absolutely nothing is known about martian life, the operational definition of a special region is a place that may allow the formation and maintenance of liquid water, on or under the surface of Mars. This paper will review the special-regions concept, the implications of recent recommendations on avoiding them, and the work of the Mars science community in providing an operational definition of those areas on Mars that are “non-special.”  相似文献   

20.
Andrea Franzolin   《Space Policy》2009,25(3):193-194
Around 50 leaders and experts from space industry, governmental and financial institutions participated in an ESA conference on “The Future of Public–Private Partnerships in Satellite Communications” in Vienna in March 2009. An increasing portion of commercial and institutional space projects are operated under the provisions of service contracts, with public–private partnerships (PPPs) becoming a significant source of financing for space programmes. The conference was based on a study initiated by ESA and performed by Euroconsult, Milbank and ESPI, outlining the main perspectives of modern PPP models in the European satellite communications sector.  相似文献   

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