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1.
《Acta Astronautica》2003,52(2-6):371-379
Under constrained budgets and rigid schedules, NASA and industry have greatly increased their utilization of small satellites to conduct low-cost planetary investigations. Recent failed small planetary science spacecraft such as Mars Polar Lander (MPL) and Mars Climate Orbiter (MCO), and impaired missions such as Mars Global Surveyor (MGS) have fueled the ongoing debate on whether NASA's “Faster, Better, Cheaper” (FBC) approach is working. Several noteworthy failures of earth-orbiting missions have occurred as well including Lewis and the Wide-field Infrared Experiment (WIRE). While recent studies have observed that FBC has resulted in lower costs and shorter development times, these benefits may have been achieved at the expense of lowering probability of success. One question remaining to be answered is when is a mission “too fast and too cheap” that it is prone to failure? This paper assesses NASA FBC missions in terms of a complexity index measured against development time and spacecraft cost. A comparison of relative failure rates of recent planetary and earth-orbiting missions are presented, and conclusions regarding dependence on system complexity are drawn.  相似文献   

2.
《Acta Astronautica》2008,62(11-12):1029-1042
A major goal of NASA's In-Space Propulsion Program is to shorten trip times for scientific planetary missions. To meet this challenge arrival speeds will increase, requiring significant braking for orbit insertion, and thus increased deceleration propellant mass that may exceed launch lift capabilities. A technology called aerocapture has been developed to expand the mission potential of exploratory probes destined for planets with suitable atmospheres. Aerocapture inserts a probe into planetary orbit via a single pass through the atmosphere using the probe's aeroshell drag to reduce velocity. The benefit of an aerocapture maneuver is a large reduction in propellant mass that may result in smaller, less costly missions and reduced mission cruise times. The methodology used to design rigid aerocapture aeroshells will be presented with an emphasis on a new systems tool under development. Current methods for fast, efficient evaluations of structural systems for exploratory vehicles to planets and moons within our solar system have been under development within NASA having limited success. Many systems tools that have been attempted applied structural mass estimation techniques based on historical data and curve fitting techniques that are difficult and cumbersome to apply to new vehicle concepts and missions. The resulting vehicle aeroshell mass may be incorrectly estimated or have high margins included to account for uncertainty. This new tool will reduce the guesswork previously found in conceptual aeroshell mass estimations.  相似文献   

3.
The New Millennium Program (NMP) consists of a series of Deep-Space and Earth Orbiting missions that are technology-driven, in contrast to the more traditional science-driven space exploration missions of the past. These flights are designed to validate technologies that will enable a new era of low-cost highly miniaturized and highly capable spacebome applications in the new millennium. In addition to the series of flight projects managed by separate flight teams, the NMP technology initiatives are managed by the following six focused technology programs: Microelectronics Systems, Autonomy, Telecommunications, Instrument Technologies and Architectures, In-Situ Instruments and Micro-electromechanical Systems, and Modular and Multifunctional Systems. Each technology program is managed as an Integrated Product Development Team (IPDT) of government, academic, and industry partners. In this paper, we will describe elements of the technology roadmap proposed by the NMP Microelectronics IPDT. Moreover, we will relate the proposed technology roadmap to existing NASA technology development programs, such as the Advanced Flight Computing (AFC) program, and the Remote Exploration and Experimentation (REE) program, which constitute part of the on-going NASA technology development pipeline. We will also describe the Microelectronics Systems technologies that have been accepted as part of the first New Millennium Deep-Space One spacecraft, which is an asteroid fly-by mission scheduled for launched in July 1998.  相似文献   

4.
《Acta Astronautica》2003,52(2-6):211-218
Aladdin, one of five Concept Study winners for NASA's Discovery AO98-OSS-04, was a mission to obtain samples from the two Martian moons using several unique mission design and sample collection techniques. The mission design enabled sample return from two bodies at the relatively low cost of a Discovery-class mission. It featured a phasing orbit, multiple flybys of the Martian moons, and a short overall mission duration. The phasing orbit greatly reduced the post-launch Δv requirement, thus permitting the use of a Delta II launch vehicle. Multiple moon flybys provided ample opportunities for sample collection and science observations. The short overall mission duration reduced program costs. Aladdin's sample collection, unlike traditional sample collection methods, used a “launch-and-catch” technique to obtain samples. Projectiles would be launched to the moon's surface during a close flyby and the ejected particles gathered for Earth return and analysis. This innovative technique, the Aladdin mission, and the possible extension of the technique to other bodies are described.  相似文献   

5.
《Acta Astronautica》2010,66(11-12):1689-1697
In late 2006, NASA's Constellation Program sponsored a study to examine the feasibility of sending a piloted Orion spacecraft to a near-Earth object. NEOs are asteroids or comets that have perihelion distances less than or equal to 1.3 astronomical units, and can have orbits that cross that of the Earth. Therefore, the most suitable targets for the Orion Crew Exploration Vehicle (CEV) are those NEOs in heliocentric orbits similar to Earth's (i.e. low inclination and low eccentricity). One of the significant advantages of this type of mission is that it strengthens and validates the foundational infrastructure of the United States Space Exploration Policy and is highly complementary to NASA's planned lunar sortie and outpost missions circa 2020. A human expedition to a NEO would not only underline the broad utility of the Orion CEV and Ares launch systems, but would also be the first human expedition to an interplanetary body beyond the Earth–Moon system. These deep space operations will present unique challenges not present in lunar missions for the onboard crew, spacecraft systems, and mission control team. Executing several piloted NEO missions will enable NASA to gain crucial deep space operational experience, which will be necessary prerequisites for the eventual human missions to Mars.Our NEO team will present and discuss the following:
  • •new mission trajectories and concepts;
  • •operational command and control considerations;
  • •expected science, operational, resource utilization, and impact mitigation returns; and
  • •continued exploration momentum and future Mars exploration benefits.
  相似文献   

6.
利用丰富的月球资源制造产品和开展各项服务对人类月球探测任务至关重要。文章对NASA月球资源原位利用项目的目标、技术路线、技术成熟度和制氧技术进行了综述,并针对适用于我国的月球资源原位利用项目提出建设性意见。  相似文献   

7.
A new class of distributed space missions is emerging which requires hundreds to thousands of satellites for real-time, distributed, multi-point sensing to accomplish long-awaited remote sensing and science objectives. These missions, stymied by the lack of a low-cost mass-producible solution, can become reality by merging the concepts of distributed satellite systems and terrestrial wireless sensor networks. However, unlike terrestrial sensor nodes, space-based nodes must survive unique environmental hazards while undergoing complex orbital dynamics. A novel sub-kilogram very small satellite design is needed to meet these requirements. Sub-kilogram satellite concepts are developing elsewhere, such as traditional picosatellites and microengineered aerospace systems. Although viable technical solutions, these technologies currently come at a high cost due to their reliance on high-density technology or custom manufacturing processes. While evaluating these technologies, two untapped technology areas became evident that uniquely encompass low cost and mass producibility by leveraging existing commercial production techniques: satellite-on-a-chip (SpaceChip) and satellite-on-a-printed circuit board (PCBSat). This paper focuses on the design, build, and test results of a prototype PCBSat with a prototype unit cost less than $300. The paper concludes with mission applications and future direction.  相似文献   

8.
《Acta Astronautica》2013,82(2):499-511
Historically, engineers at the National Aeronautics and Space Administration (NASA) had few opportunities or incentives to share their technical expertise across the Agency. Its center- and project-focused culture often meant that knowledge never left organizational and geographic boundaries. The need to develop a knowledge sharing culture became critical as a result of increasingly complex missions, closeout of the Shuttle Program, and a new generation of engineers entering the workforce. To address this need, the Office of the Chief Engineer established communities of practice on the NASA Engineering Network. These communities were strategically aligned with NASA's core competencies in such disciplines as avionics, flight mechanics, life support, propulsion, structures, loads and dynamics, human factors, and guidance, navigation, and control. This paper is a case study of NASA's implementation of a system that would identify and develop communities, from establishing simple websites that compiled discipline-specific resources to fostering a knowledge-sharing environment through collaborative and interactive technologies. It includes qualitative evidence of improved availability and transfer of knowledge. It focuses on capabilities that increased knowledge exchange such as a custom-made Ask An Expert system, community contact lists, publication of key resources, and submission forms that allowed any user to propose content for the sites. It discusses the peer relationships that developed through the communities and the leadership and infrastructure that made them possible.  相似文献   

9.
In order to meet the growing global requirement for affordable missions beyond Low Earth Orbit, two types of platform are under design at the Surrey Space Centre. The first platform is a derivative of Surrey's UoSAT-12 minisatellite, launched in April 1999 and operating successfully in-orbit. The minisatellite has been modified to accommodate a propulsion system capable of delivering up to 1700 m/s delta-V, enabling it to support a wide range of very low cost missions to LaGrange points, Near-Earth Objects, and the Moon. A mission to the Moon - dubbed “MoonShine” - is proposed as the first demonstration of the modified minisatellite beyond LEO. The second platform - Surrey's Interplanetary Platform - has been designed to support missions with delta-V requirements up to 3200 m/s, making it ideal for low cost missions to Mars and Venus, as well as Near Earth Objects (NEOs) and other interplanetary trajectories. Analysis has proved mission feasibility, identifying key challenges in both missions for developing cost-effective techniques for: spacecraft propulsion; navigation; autonomous operations; and a reliable safe mode strategy. To reduce mission risk, inherently failure resistant lunar and interplanetary trajectories are under study. In order to significantly reduce cost and increase reliability, both platforms can communicate with low-cost ground stations and exploit Surrey's experience in autonomous operations. The lunar minisatellite can provide up to 70 kg payload margin in lunar orbit for a total mission cost US$16–25 M. The interplanetary platform can deliver 20 kg of scientific payload to Mars or Venus orbit for a mission cost US$25–50 M. Together, the platforms will enable regular flight of payloads to the Moon and interplanetary space at unprecedented low cost. This paper outlines key systems engineering issues for the proposed Lunar Minisatellite and interplanetary Platform Missions, and describes the accommodation and performance offered to planetary payloads.  相似文献   

10.
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   


11.
With the development of several key technologies, nanosatellites are emerging as important vehicles for carrying out technology demonstrations and space science research. Nanosatellites are attractive for several reasons, the most important being that they do not involve the prohibitive costs of a conventional satellite launch. One key enabling technology is in the area of battery technology. In this paper, we focus on the characterization of battery technologies suitable for nanosatellites.Several battery chemistries are examined in order to find a type suitable for typical nanosatellite missions. As a baseline mission, we examine York University's 1U CubeSat mission for its power budget and power requirements. Several types of commercially available batteries are examined for their applicability to CubeSat missions. We also describe the procedures and results from a series of environmental tests for a set of Lithium Polymer batteries from two manufacturers.  相似文献   

12.
Space science missions are increasingly challenged today: in ambition, by increasingly sophisticated hypotheses tested; in development, by the increasing complexity of advanced technologies; in budgeting, by the decline of flagship-class mission opportunities; in management, by expectations for breakthrough science despite a risk-averse programmatic climate; and in planning, by increasing competition for scarce resources. How are the space-science missions of tomorrow being formulated? The paper describes the JPL Innovation Foundry, created in 2011, to respond to this evolving context. The Foundry integrates methods, tools, and experts that span the mission concept lifecycle. Grounded in JPL's heritage of missions, flight instruments, mission proposals, and concept innovation, the Foundry seeks to provide continuity of support and cost-effective, on-call access to the right domain experts at the right time, as science definition teams and Principal Investigators mature mission ideas from “cocktail napkin” to PDR. The Foundry blends JPL capabilities in proposal development and concurrent engineering, including Team X, with new approaches for open-ended concept exploration in earlier, cost-constrained phases, and with ongoing research and technology projects. It applies complexity and cost models, project-formulation lessons learned, and strategy analyses appropriate to each level of concept maturity. The Foundry is organizationally integrated with JPL formulation program offices; staffed by JPL's line organizations for engineering, science, and costing; and overseen by senior Laboratory leaders to assure experienced coordination and review. Incubation of each concept is tailored depending on its maturity and proposal history, and its highest-leverage modeling and analysis needs.  相似文献   

13.
Canada is a space power with unique technical niches that support opportunities for collaboration on space technologies. When U.S.-origin space technologies are involved Canada's ability to collaborate internationally may be conditional on US law and policy. As a result, US export control law can be directly linked to the success or failure of Canadian collaboration. This article examines the strategic impact of U.S. export controls on Canadian autonomy to collaborate on international missions, including multi-use missions. Canadian space export control policy is also examined more broadly with the goal of providing specific policy recommendations that will enhance Canada's future as an international space actor.  相似文献   

14.
In less than a decade, Cubesats have evolved from purely educational tools to a standard platform for technology demonstration and scientific instrumentation. The use of COTS (Commercial-Off-The-Shelf) components and the ongoing miniaturization of several technologies have already led to scattered instances of missions with promising scientific value. Furthermore, advantages in terms of development cost and development time with respect to larger satellites, as well as the possibility of launching several dozens of Cubesats with a single rocket launch, have brought forth the potential for radically new mission architectures consisting of very large constellations or clusters of Cubesats. These architectures promise to combine the temporal resolution of GEO missions with the spatial resolution of LEO missions, thus breaking a traditional trade-off in Earth observation mission design. This paper assesses the current capabilities of Cubesats with respect to potential employment in Earth observation missions. A thorough review of Cubesat bus technology capabilities is performed, identifying potential limitations and their implications on 17 different Earth observation payload technologies. These results are matched to an exhaustive review of scientific requirements in the field of Earth observation, assessing the possibilities of Cubesats to cope with the requirements set for each one of 21 measurement categories. Based on this review, several Earth observation measurements are identified that can potentially be compatible with the current state-of-the-art of Cubesat technology although some of them have actually never been addressed by any Cubesat mission. Simultaneously, other measurements are identified which are unlikely to be performed by Cubesats in the next few years due to insuperable constraints. Ultimately, this paper is intended to supply a box of ideas for universities to design future Cubesat missions with high scientific payoff.  相似文献   

15.
《Acta Astronautica》1999,44(2-4):187-192
The Advanced Deep Space System Development Program is managed by the Jet Propulsion Laboratory for NASA and is also called X2000. X2000 is organized to create advanced flight and ground systems for the exploration of the outer planets and beyond; it has been created to develop the engineering elements of flight and ground systems. Payloads will be developed by another team. Each X2000 delivery gets its requirements from a set of planned missions, or “mission customers”.The X2000 First Delivery Project supports missions to the Sun (to 4 solar radii), Europa (looking for a liquid ocean), Mars (in support of several Mars missions including a sample return), a comet (including a sample return), and Pluto followed by a trip into the Kuiper belt. This set of missions leads to some outstanding requirements:
  • 1.1. Long-life (10–12 years)
  • 2.2. Total Ionizing Dose of 4 Mrad (for a Europa Orbiter)
  • 3.3. Average power consumption less than or equal to 150 Watts
  • 4.4. Autonomous operations that result in an extreme reduction in operations costs
This paper describes the X2000 first delivery and its technologies following a brief overview of the program.  相似文献   

16.
《Acta Astronautica》2003,52(2-6):281-287
Genesis is the fifth mission selected as part of NASA's Discovery Program. The objective of Genesis is to collect solar wind samples for a period of approximately 2 years while in a halo orbit about the Sun–Earth colinear libration point, L1, located between the Sun and Earth. At the end of this period, the spacecraft follows a free-return trajectory with the samples delivered to a specific recovery point on the Earth for subsequent analysis. This type of sample return has never been attempted before and presents a formidable challenge, particularly with regard to planning and execution of propulsive maneuvers. Moreover, since the original inception, additional challenges have arisen as a result of emerging spacecraft design concerns and operational constraints. This paper will describe how these challenges have been met to date in the context of the better-faster-cheaper paradigm. [This paper addresses an earlier mission design, as of May 2000.]  相似文献   

17.
Only one of NASA's planetary science flight missions in the past 30 years has been led by a women scientist as Principal Investigator. The number of senior women in the field is small, but women are still underutilized, as seen by a cohort age analysis correlating with median ages for various key science roles. Worse, the more junior women are not joining missions as Co-Investigators and Participating Scientists at rates approaching their representation in the field of planetary science. In fact, they are underutilized in these roles not by a few percent, but by greater than a factor of two. The pipeline of women gaining mission experience today is increasing, but it is not keeping pace with the rate that women are now choosing to stay in the field for postdoctoral studies and beyond. The numbers definitively show for the first time that, for whatever reason, women are still underrepresented in mission leadership at NASA.  相似文献   

18.
Science return and high bandwidth communications are one of the key issues to support the foreseen endeavours on next generation missions [J.L. Gerner, Telemetry, tracking and command of satellites—a perspective, TT&C 2004 Workshop, 7–9 September 2004]. Interplanetary telecommunication systems are required that support the foreseen endeavours. Given the same constraints in terms of mass, power and volume a laser communications terminal can offer an increase in telemetry bandwidth over classical RF technology allowing for a variety of new options, specifically to missions that require large distances, such as to the Moon, to liberation points L1 and L2, ultimately aiming at deep space missions. An increase in telemetry data rate allows the mission to consider the processing of raw scientific data to take place on ground, making use of latest technology further developed during the cruise phase of the probe, rather than applying data pre-processing on-board the satellite. Enhanced sensing techniques that generate more science data return could be used and access to data during flight could be faster. Results of on-going activities will be presented, comprising PPM laser communications and advanced tracking concepts. An overview will be given of the system concept for an integrated RF-optical TT&C transponder. Results will be shown from hardware tests on communications performance in inter-island test campaigns.  相似文献   

19.
The performance of a small and low-cost metal chamber built to simulate the pressure and temperature conditions of lunar surface was assessed and the results are presented. This chamber is intended for studying the physical properties of lunar surface and subsurface (using soil simulants) and also to validate the technology readiness of certain newly developed payloads planned for future lunar surface missions (Lander/Rover). It is possible to reach down to ∼10−7 Pa under specific conditions and maintain the temperature of the sample under investigation to lunar day and night temperatures. The designed system has been subjected to various tests to evaluate its performance and suitability for carrying out experiments in a simulated lunar environment.  相似文献   

20.
《Acta Astronautica》2001,48(5-12):711-721
Early human missions to the Moon have landed on six different sites on the lunar surface. These have all been in the low-latitude regions of the near side of the Moon. Early missions were designed primarily to assure crew safety rather than for scientific value. While the later missions added increasingly more challenging science, they remained restricted to near-side, low-latitude sites. Since the 1970s, we have learned considerably more about lunar planetology and resources. A return within the next five to ten years can greatly stimulate future human space exploration activities. We can learn much more about the distribution of lunar resources, especially about hydrogen, hydrated minerals, and water ice because they appear to be abundant near the lunar poles. The presence of hydrogen opens the possibility of industrial use of lunar resources to provide fuel for space transportation throughout the solar system.This paper discusses the rationale for near-term return of human crews to the Moon, and the advantages to be gained by selecting the Moon as the next target for human missions beyond low-Earth orbit. It describes a systems architecture for early missions, including transportation and habitation aspects. Specifically, we describe a primary transportation architecture that emphasizes existing Earth-to-orbit transportation systems, using expendable launch vehicles for cargo delivery and the Space Shuttle and its derivatives for human transportation. Transfer nodes should be located at the International Space Station (ISS) and at the Earth-Moon L1 (libration point).Each of the major systems is described, and the requisite technology readiness is assessed. These systems include Earth-to-orbit transportation, lunar transfer, lunar descent and landing, surface habitation and mobility, and return to Earth. With optimum reliance on currently existing space systems and a technology readiness assessment, we estimate the minimum development time required and perform order-of-magnitude cost estimates of a near-term human lunar mission.  相似文献   

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