Technology for Small Spacecraft (1994) / Chapter Skim
Currently Skimming:
11 Overall Findings and Recommendations
11 Overall Findings and Recommendations
Pages 83-102
The Chapter Skim interface presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter.
Select key terms on the right to highlight them within pages of the chapter.
From page 83... ...
lessexpensive missions can help to promote structural and cultural changes that are vital to the future of the space program considering the current budgetary and political environment. These changes include increased opportunities for infusion of new technology in ongoing programs, along with an increased tolerance for technological risk; overall improvements in program responsiveness, versatility, and cost-effectiveness; and economic competitiveness in both aerospace and nonaerospace industries.
|
From page 84... ...
to review the National Aeronautics and Space Administration's (NASA) plans for a new small spacecraft technology-development program; review NASA's current technology program and priorities for relevance to small spacecraft, launch vehicles, and ground operations; examine small spacecraft technology programs of other government agencies; assess technology efforts in industry that are relevant to small spacecraft, launch vehicles, and ground operations; and identify technology gaps and overlaps and prioritize areas in which greater investments are likely to have high payoff, considering the current and projected budgets, the NASA mission statement (see Appendix A)
|
From page 85... ...
Assessment of the NASA Technology Priorities for Relevance to Small Spacecraft, Launch Vehicles, and Ground Operations The establishment of the Small Spacecraft Technology Initiative appears to have heightened emphasis, in NASA technology planning circles, on team operations involving industry, university, and NASA interaction on specific space missions, with accentuated industry leadership. "Customer needs," "user needs," anti technology transfer capability have received considerable emphasis from NASA management as the primary strivers of NASA's research and development efforts.
|
From page 86... ...
Since the fiscal year 1995 budget only recently was submitted to Congress, it was not clear at the time of this report whether Congress would support NASA's $47.9 million request for the Small Spacecraft Technology Initiative. While small spacecraft based on currently available technology have significant capability, their ability to conduct more-meaningful science programs at affordable cost could be greatly enhanced through technology development.
|
From page 87... ...
the Congress for the substantial increase. Small Spacecraft Technologies of Other Government Agencies and Technology Efforts in Industry that are Relevant to Small Spacecraft, Launch Vehicles, and Ground Operations The pane!
|
From page 88... ...
Air Force Phillips Laboratory NASA, Industry Polymer matrix composites for primary Industry structures High speed switching from the Advanced Communications Technology Satellite (Ka band) Radio frequency satellite link components Radio frequency phased array antennas Solid-state amplifiers NASA, Industry NASA, Industry NASA, Industry NASA, Industry .
|
From page 89... ...
BMDO-developed instruments using passive and/or active sensors: star trackers, near infrared camera, long-wavelength infrared camera, ultraviolet/visible infrared camera, laser imaging and detection ranger Industry BMDO, Industry Industry, Naval Research Laboratory Industry Industry U.S. Air Force Phillips Laboratory, Industry, NASA BMDO NASA-developed instruments for the NASA Mission to Planet Earth program Aluminum-lithium alloys for propellant tanks and other structures Graphite epoxy for propellant tanks and Industry other structures NASA, Industry *
|
From page 90... ...
Air Force Phillips Laboratory, Industry NASA, JPL, Industry Amorphous silicon, copper indium diselenide, cadmium telluride, indium phosphide on germanium, and multibandgap cells Thin-film cells Ultra-light flexible panels and flexible arrays Nickel metal hydride batteries Lithium batteries Advanced energy conversion systems (Stirling, thermophotovoltaic, and alkali metal thermoelectric converters)
|
From page 91... ...
Navy, Industry U.S. Air Force Phillips Laboratory Industry JPL, DOE, Industry Industry NASA, Naval Research Laboratory Industry, NASA Industry, Naval Research Laboratory Industry, NASA, Universities Industry, Universities BMDO, Industry, Lawrence Livermore National Laboratory BMDO, Industry BMDO, Industry ARPA ARPA, Industry Applied Physics Laboratory, Naval Research Laboratory Applied Physics Laboratory
|
From page 92... ...
ROBOTICS Remotely programmed microrovers JPL Tools for autonomous operation of NASA, ARPA, Industry mlcrorovers Spaceborne geophysical sampling device LAUNCH VEHICLES Advanced composite materials for fabrication Industry of intertank structure, skirts, and payload shrouds Lower-cost solid- and liquid-rocket motor components through use of advanced manufacturing methods Hybrid propellant motors and stages Reusable cryogenic and tripropellant propulsion components (injectors, thrust chambers, pumps) for application to single stage-to-orbit Clean propellants using higher-performance ingredients such as ammonium dinitramide Clean solid propellants exploiting ammonium nitrate, solution propellant, and scavenged approaches NASA, Applied Physics Laboratory U.S.
|
From page 93... ...
Prioritized Areas in Which Greater Investments are Likely to Have High Payoff Considering Current and Projected Budgets, the NASA Mission Statement, and the Needs of Industries That Utilize Space As stated in Chapter i, the principal deterrent to an expanded space program, both in NASA and commercially, is high cost. This is true for NASA because of today's budgetary and political climate and for industry because of the high cost in providing a 93
|
From page 94... ...
that included the following: the potential to reduce mission cost; the cost to develop the technology; the potential to reduce weight (permitting a higher payload mass fraction or use of a smaller launch vehicle) ; the likelihood of a successful development; and the potential to enable key mission goals.
|
From page 95... ...
technologies to reduce cost ant! improve efficiency of up-front systems engineering, launch, and mission operations; GPS for precision guidance and control; high-efficiency solar electric power generation and electric propulsion; hybrid propulsion for launch vehicles; and miniaturization of electronic devices.
|
From page 96... ...
Extensive development work on both the solar power and electric propulsion technologies has been conducted in the past, but a concentrated, well-funded, clevelopment activity is needled to bring these technologies to fruition. Hybrid propulsion is a technology that has great potential for application to small spacecraft launch vehicles and has been under development for some time.
|
From page 97... ...
These should utilize expert systems when appropriate, including, as a minimum, the following: on-board health monitoring and checkout and, where economical, fault correction, for both the launch vehicle and the spacecraft; techniques for remote system checkout; automated preparation of flight software for guidance and control of both the launch vehicle and spacecraft; a set of standard hardware interfaces for small launch vehicles and spacecraft; on-board launch trajectory determination for range safety tracking; spacecraft accessibility late in the countdown; and reduction of launch pad safety requirements through use of technologies such as hybrid propulsion and nonexplosive separation devices. Propulsion An aggressive program should be established to demonstrate, in ground tests, the life of xenon ion propulsion systems that operate at power levels in the range from about 0.5 kilowatt to about 2.5 kilowatts for lifetimes of up to 8,000 hours.
|
From page 98... ...
Launch Vehicle Technology Hybrid rocket motors that simulate operational requirements, thrust level, and burn duration for small launch vehicles
|
From page 99... ...
In the long-term, work on other advanced solar cell and solar array technology, including thin-film cell development, inflatable arrays, and flexible blanket wing APSA arrays, should continue at an increased funding level, with the goal of achieving a specific power of 300 watts per kilogram. Structures and Materials Research on simple, low-cost deployable booms and surfaces should be emphasized.
|
From page 100... ...
A research and development program should be directed toward the development of miniaturized, power-efficient, high performance instruments in the following areas: multifrequency radar altimeter and scatterometer systems; advanced coherent lidar systems; multispectral Earth observation systems operating in the ultraviolet, visible, and infrared wavelengths, employing lightweight optics and advanced detector array technology; advanced, passive, larger-aperture, high-sensitivity, low-weight, microwave radiometry employing lightweight deployable antennas, room-temperature superconducting sensors, and advanced on-board processors; and lightweight, deployable-mirror optical systems with deformable mirrors correctable to the diffraction limit, for ultraviolet, infrared, and visible long baseline interferometry using several small spacecraft, ultimately resulting in an extremely large-aperture phased array for astronomical observations. _ Robotics and Automation Autonomous systems and artificial intelligence should be developed for application to microrovers.
|
From page 101... ...
Launch Vehicle Technology Although the Panel on Small Spacecraft Technology believes it has identified several areas with potential for reducing small spacecraft launch vehicle costs, the panel was not able to identify a technology program that would achieve the desired cost of $5 million to $7 million per launch. The panel, therefore, recommends that NASA conduct a study of proposed, new launch vehicles targeted for the small payload market; with a goal of $5 million to $7 million per launch; to determine the cost benefits associated with the introduction of new technology, including unique concepts, new hardware designs, new materials, and manufacturing methods.
|
From page 102... ...
Such action will help the commercial sector maintain or improve reliability. Development of advanced manufacturing methods directed toward producibility and cost reduction of small spacecraft launch vehicles should be continued.
|
Key Terms
This material may be derived from roughly machine-read images, and so is provided only to facilitate research.
More
information on Chapter Skim is available.