NASA Research Research Articles

Passive millimeter wave imaging considerations for tactical aircraft

Air Force, Army, Navy, and NASA Research Laboratories, in addition to major aerospace companies, are considering millimeter wave (MMW) imaging technology as an enhancement to sensor suits on both occupied and unoccupied vehicles. This is a review of the basic technology involved in MMW imaging and some of the programs and products that might benefit from passive day or night imaging through mist, haze, fog, clouds, smoke and/or dust. Potential applications include UAV surveillance of ground vehicles, airborne approach to airfields, tankers, flight leaders, and detection of airborne targets, including stealth aircraft.

Uncertain structural dynamics of aircraft panels and fuzzy structures analysis

Aircraft fuselage panels, seemingly simple structures, are actually complex because of the uncertainty of the attachments of the frame stiffeners and longitudinal stringers. It is clearly important to understand the dynamics of these panels because of the subsequent radiation into the passenger cabin, even when complete information is not available for all portions of the finite-element model. Over the last few years a fuzzy structures analysis (FSA) approach has been undertaken at Penn State and NASA Langley to quantify the uncertainty in modeling aircraft panels. A new MSC.Nastran [MSC.Software Corp. (Santa Ana, CA)] Direct Matrix Abstraction Program (DMAP) code was written and tested [AIAA paper 2001-1320, 42nd AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conf., Seattle, WA, 16 April 2001] and was applied to simple fuselage panel models [J. Acoust. Soc. Am. 109, 2410(A) (2001)]. Recently the work has focused on understanding the dynamics of a realistic aluminum fuselage panel, typical of today’s aircraft construction. This presentation will provide an overview of the research and recent results will be given for the fuselage panel. Comparison between experiments and the FSA results will be shown for different fuzzy input parameters. [Work supported by NASA Research Cooperative Agreement NCC-1-382.]

Ozone depletion observed by the Airborne Submillimeter Radiometer (ASUR) during the Arctic winter 1999/2000

In the winter 1999/2000 the Airborne Submillimeter Radiometer (ASUR) participated in the Stratospheric Aerosol and Gas Experiment III Ozone Loss and Validation Experiment/Third European Stratospheric Experiment on Ozone project on board the NASA research aircraft DC‐8. During three deployments in early December 1999, late January, and early March 2000, the ASUR instrument took various measurements of ozone and key species related to stratospheric ozone chemistry. After the sunlight reached the vortex region in January 2000 peak values of about 1.8 ppb ClO were measured by ASUR. There was nearly no ozone destruction observed during the period between mid December 1999 and late January 2000. As expected from ASUR observation of high chlorine activation and continuously low temperatures until mid March, significant ozone depletion was observed between late January and mid March 2000. In order to determine ozone loss it is important to separate dynamical and chemical effects. Since N2O is a good tracer due to its chemical stability in the lower stratosphere for determining ozone changes due to descent of air, ozone loss can be estimated from simultaneous measurements of ozone and N2O by ASUR. Between mid December 1999 and mid March 2000 a chemical ozone loss of about 30% (eq 1.1 ppm) in the altitude range between 19.0 and 22.2 km and of about 40% (eq 1.15 ppm) between 16.0 and 18.1 km was observed. The air masses subsided 2.1–3.2 km in the lower stratosphere due to diabatic descent in the period from mid December 1999 to mid March 2000 as derived from ASUR N2O measurements. Vortex‐averaged ASUR measurements of ozone are systematical greater than results from the Global Ozone Monitoring Experiment (GOME) which has a similar vertical resolution than ASUR. This, however, has little impact on the determination of delta ozone and chemical loss estimates.

Gathering Data On Cosmic-Ray Electrons

A 60 million-cu-ft NASA research balloon, launched from Lynn Lake in northwestern Manitoba on Aug. 25, slowly drifted to 161,000 feet in the rarefied upper reaches of the stratosphere, setting a re...

Analyses of in‐situ airborne volcanic ash from the February 2000 eruption of Hekla Volcano, Iceland

A McDonnell‐Douglas DC‐8 NASA research aircraft inadvertently flew into an airborne volcanic ash plume from the 26 February 2000 eruption of Hekla Volcano. Filter samples from the aircraft were compared with “normal use” and “pristine clean” filters using SEM, energy‐dispersive x‐ray spectrometer, and Nicolet FTIR spectrophotometer analyses. These analyses confirm that the DC‐8 encountered airborne volcanic ash from Hekla Volcano. This result is supported by independent onboard heated aerosol observations at the time of the encounter. The analyses further demonstrate the ambiguous nature of the dual band thermal IR (“split window”) method for detecting volcanic ash from the point of view of aviation safety. They also highlight the utility of in situ aircraft filter‐based observations of volcanic aerosols for scientific purposes.

Development of CORBA-based engineering applications from legacy Fortran programs

A majority of scientific and engineering applications in aerodynamics and solid mechanics are written in Fortran. To reduce the high cost of software development, NASA researchers reuse most of the legacy Fortran codes instead of developing them from scratch in the numerical propulsion system simulation project. In this paper, we present an efficient methodology for integrating legacy applications written in Fortran into a distributed object framework. Issues and strategies regarding the conversion and wrapping of Fortran codes into common object request broker architecture objects are discussed. Fortran codes are modified as little as possible when they are decomposed into modules and wrapped as objects. We implement a wrapper generator which takes the Fortran application as input and generates the C++ wrapper files and interface definition language file. Tedious programming tasks for wrapping the codes can therefore be reduced.

Management of Application QOS-level Adaptation for Real-Time Systems

Allocating computing resources to various applications running on distributed computing platforms in order to satisfy real-time quality-of-service (QoS) requirements is an important problem, as is evident from a recent NASA research challenge problem concerning an autonomous hot-spot convergence system for the next-generation constellation-based satellite sensor webs. This paper presents a new resource management mechanism based on service levels and utility, and motivated by the hot-spot example, to address this problem. Existing approaches to adaptive resource and QoS management typically perform either reallocation of resources or adaptation of application QoS levels in response to dynamic environment changes. While success has been achieved with both of these approaches, this paper demonstrates the potential synergy of implementing both types of techniques. A proof-of-concept implementation is shown and our initial experimental results are analyzed.

Measuring the economic returns from successful NASA life sciences technology transfers.

Since 1958 NASA has invested approximately $3.7 billion in life sciences R&D in the support of the successful human space flight program. There are numerous studies documenting the spin-off technologies that can be traced to NASA research and development activities. Most of these studies describe the technologies and their uses; however only a few measure the economic impact of the spin-offs and most of these are benefit/cost studies that tend to overstate benefits or underestimate costs. This study takes a different approach, measuring only economic impacts to the companies that developed successful spin-off products from NASA life sciences investments. A personal interview was conducted with each company and the benefits are conservatively estimated as the value-added by the NASA technology to the company's output and the amount of additional private R&D stimulated by the NASA R&D. This pilot study of fifteen companies, using a very conservative measurement technique, found a large return to companies that have successfully commercialized NASA life sciences spin-off products. Value-added benefits totaled over $1.5 billion and a NASA R&D total investment in these 15 technologies of $64 million was found to stimulate an additional $200 million in private R&D. The study also found that the largest benefits were from products developed and marketed by large companies, primarily because these companies had the financial and marketing resources to work on a scale unavailable to smaller companies. Many of the small companies reported very profitable product-lines as well as documented evidence of benefits extending to the commercial users of their products. However, the smaller companies often lacked either the ability or the desire to expand into much larger scale production. NASA and other government technology transfer programs may be overlooking an opportunity to enlarge the economic benefits from their spin-off technologies. When a federal R&D grant or contract ends, the formal relationship between the agency and the company also usually ends. However, the companies continue to use the prior connection to NASA for advertising and for developing new business partners. One recommendation of this study is for NASA to be more proactive with "alumni" companies and to help open additional financial and marketing doors for these companies.

Hyper-X Stage Separation Wind-Tunnel Test Program

NASA's Hyper-X research program was developed primarily to flight demonstrate a supersonic combustion ramjet engine, fully integrated with a forebody designed to tailor inlet flow conditions and a free expansion nozzle/afterbody to produce positive thrust at design flight conditions. With a point-designed propulsion system the vehicle must depend on some other means for boost to its design flight condition. Clean separation from this initial propulsion system stage within less than a second is critical to the success of the flight. This paper discusses the early planning activity, background, and chronology that developed the series of wind-tunnel tests to support multi-degree-of-freedom simulation of the separation process. Representative results from each series of tests are presented, and issues and concerns during the process and current status are highlighted.

Buckets: A new digital library technology for preserving NASA research

A fundamental task of research organizations is the preservation and dissemination of their intellectual output. Historically, this has been accomplished with hard copy formats through a multitiered approach of using the open literature, self-publishing, and an array of cooperative libraries and depositories. It can be argued that the historical approach is less than optimal with respect to results achieved and resources expended. However, there have been recent advances in the area of digital libraries (DLs) that address some of the shortcomings of traditional hard copy preservation and dissemination. One of these technologies is “buckets,” an aggregative, intelligent construct for publishing. Buckets exist within the “Smart Object, Dumb Archive” (SODA) DL model, which can be summarized as promoting the importance and responsibility of individual information objects and reducing the role of traditional archives and database systems. The goal is that smart objects will be independent of and more resilient to the transient nature of information systems. This paper examines the motivation for buckets and SODA, as well as discussing some initial experiences in using these DL technologies in some US government research laboratories in NASA, the Air Force, and the Department of Energy.

Application of fuzzy structures analysis to aircraft panels

In 2000 a research implementation of Christian Soize’s fuzzy structures analysis procedures were implemented by Sparrow in the commercial finite element program MSC/NASTRAN [MSC Software Corp. (Los Angeles, CA)] using its direct matrix abstraction program (DMAP) capability coupled with MATLAB [Mathworks, Inc. (Natick, MA)]. The background and implementation details of the new DMAP code were recently given [AIAA paper 2001–1320, Non-Deterministic Approaches Forum, 42nd AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conf., Seattle, WA, 2001]. The present talk will describe the application of the new code to two prototypical aircraft panels: a small 0.96 by 0.19 m panel with one longitudinal stringer and a larger 1.8 by 1.2 m panel including six longitudinal stringers and four equally spaced frame stiffeners. The smaller and larger panels were modeled in NASTRAN as having approximately 7900 and 60<th>000 degrees of freedom, respectively. In these studies the attachment points between the stringers and skin were assumed to be fuzzy. Results will be described comparing the fuzzy and nonfuzzy finite element predictions to experimental vibration results. [Work supported by NASA Research Cooperative Agreement NCC-1-382.]

ANTS in space?

Inspired by the accomplishments of social insects, and perhaps disappointed by the failures of conventional robots, NASA is planning to send a swarm of miniature spacecraft to explore the Asteroid Belt. The collective intelligence of the swarm – to be composed of hundreds of tiny, independent spacecraft called ANTS (‘Autonomous Nano Technology Swarm’) – will be based on that of earthbound species, such as ants and wasps. After traveling to the Asteroid Belt, the ANTS will assume different roles: some will act as rulers, others as messengers, but most will be workers. Each worker will carry a single instrument, such as a magnetometer or a gamma-ray sensor, and will perform a single specified task. The collective nature of the swarm is supposed to make the system robust: the loss of a few spacecraft will not cripple the mission. By performing their tasks individually but later swapping knowledge, the ANTS will behave as a single, extended organism, more intelligent that the sum of its parts. Perhaps the real challenge is whether the same be said of the NASA research group… MW

New microgravity fundamental physics research areas in the ISS era

NASA's microgravity fundamental physics program has used the Space Shuttle to perform high resolutions experiments in space. As we come to the end of the Shuttle era, we will begin to perform research aboard the ISS. A large stable of ground based experiments have been selected from NASA Research Announcements in a variety of disciplines. These investigations will form the backbone from which to select future flight candidates. Research in Laser Cooling and Atomic Physics will enable us to operate highly precise clocks in space. Low temperature physics experiments will use a liquid helium facility with a six-month lifetime. This facility can also support experiments in gravitational physics. Researchers in biological physics will be offered an opportunity to develop future experiments that can benefit from space experimentation. An overview of the future research directions and the benefits to the community of performing research aboard the ISS will be presented.

Editorial: Book Reviews, Research Grants

As I write this, we are preparing again for the annual convention of the NASA and beginning to think about the next year. The role of senior editor will pass to Graeme Sullivan, and we have talked about continuity and change within our arrangements for Studies. Continuity is the more important. As I think about my brief spell as editor, there are few things I would change about Studies' contents or procedures. They reflect quite directly the topics and issues that concern the readers (at least those that submit manuscripts) and reflect too their attitudes and abilities. This is how it should be. One of the few things I would like to change is Studies' record with book reviews. Book reviews are helpful to the for many reasons. They not only alert us to new books, but they can various ways help us to understand them. They can compare new books with those that already exist, relate them to new trends or movements, raise issues of approach, ideology, and coverage. I think that Studies, as the major academic journal of the Association, should have a more active book review section. It seems a reasonable goal that there should be no significant new book our published without review Studies. Of course, I recognize that it is sometimes a question whether a book is in our field or not; but the major reason we publish so few book reviews is that few are submitted. So this a call (again: I remember Graeme Chalmers issued a similar one during his editorship) to readers to consider submitting a review of a significant book, or books, and moreover, to make the review itself significant. Book reviews do not have to be short, though many of the best are. They do need to meet the same writing standards as other manuscripts do, but there is plenty of space Studies for good ones. The results of the new annual research grant competition held by the NASA Research Commission are now available. Readers will remember that the first call for proposals focused on student learning secondary art education, and the second year will have the same focus. We have high hopes that this program will result significant and cumulative research and that the results will eventually be published the pages of Studies. Below, I will append an announcement of the awards by Tom Brewer, the research commission chair. To make space for the announcement, I will simply say of the contents of this issue that they are as various as those of the past, and the issue has been an equal pleasure to prepare. It says again, I think, that there is plenty of life and variety art education. …

Scientific research on LTMPF on the International Space Station

The Low-Temperature Microgravity Physics Facility (LTMPF) is a state-of-the-art facility for long duration science investigations in microgravity and at low temperature. It will be reusable with full electronics, software and communication support. With the first launch scheduled in 2004, it will have at least five months cryogen lifetime in space and will reside on the Japanese Experiment Module, Exposed Facility (JEM-EF) of the International Space Station (ISS). High-resolution sensors of temperature, pressure and capacitance will be available to accommodate a wide variety of experiments. A LTMPF overview and design requirements will be presented. Experiment selections and approvals are through the NASA Research Announcement and peer-review processes. Three of the current six candidate experiments involve international collaborations.

G.A. Snyder, C.R. Neal and W.G. Ernst (Eds.) Planetary Petrology and Geochemistry: the Lawrence A. Taylor 60th Birthday Volume. Boulder, Colorado (Geological Society of America) 1999. vi + 277 pp. Price $89.95 (postpaid). ISBN 0-9665-869-1-3

G.A. Snyder, C.R. Neal and W.G. Ernst (Eds.) Planetary Petrology and Geochemistry: the Lawrence A. Taylor 60th Birthday Volume. Boulder, Colorado (Geological Society of America) 1999. vi + 277 pp. Price $89.95 (postpaid). ISBN 0-9665-869-1-3 - Volume 64 Issue 3

Research Opportunities on the Low Temperature Microgravity Physics Facility (LTMPF) on the International Space Station

The Low Temperature Microgravity Physics Facility (LTMPF) is a state-of-the-art facility for long duration science investigations whose objectives can only be achieved in microgravity and at low temperature. LTMPF consists of two reusable, cryogenic facilities with self-contained electronics, software and communication capabilities. The Facility will be first launched by Japanese HIIA Rocket in 2004 with at least five months cryogen lifetime on the Japanese Experiment Module Exposed Facility (JEM EF) of the International Space Station (ISS). Future missions will be launched and retrieved by the Space Shuttle. A number of high precision sensors of temperature, pressure and capacitance will be available, which can be further tailored to accommodate a wide variety of low temperature experiments. This paper will describe the LTMPF and its goals and design requirements. Currently there are six candidate experiments in the flight definition phase to fly on LTMPF. Future candidate experiments will be selected through the NASA Research Announcement(NRA) process. Opportunities for utilization and collaboration with international partners will also be discussed.

Radar and Optical Characterization of an Anomalous Orbital Debris Population

Analysis of orbital debris data collected by the Haystack radar have shown an anomalously high concentration of debris between the altitudes of 800 and 1000 km. Indications from the Haystack data are that the debris range in size from 8 mm to 2 cm and that they are spherical in shape. Previous work by NASA researchers has shown the likely origin to be the leaking of liquid coolant from the nuclear power sources of a now defunct Soviet spacebased series of ocean surveillance satellites. We report on a project at Massachusetts Institute of Technology’s Lincoln Laboratory to detect, track, and characterize a small sample of the anomalousdebris using ground-based radars and telescopes. Our goal was to provide evidence supporting or refuting the NASA conclusions. We have determined that the size, shape, density, and surface properties of the debris are consistent with the hypothesis that it is liquid, eutectic sodium–potassium coolant like that used in the Soviet satellites. The techniques used to detect and track the debris are discussed. The radar and optical data used to characterize the debris are also presented.

Congress talks tough on funds for NASA and basic research

washington US science lobbyists face a tough battle to restore research funding at the space agency NASA and the National Science Foundation in the face of Congressional efforts to impose cuts.

Spaceflight opportunities on the ISS for plant research — The ESA perspective

Two ESA facilities will be available for plant research and other biological experiments on the International Space Station: the Modular Cultivation System (MCS) and BIOLAB. While BIOLAB will be launched with the European “Columbus” Module, MCS will be part of the Early Utilisation Agreement with NASA and integrated in the US Lab. Both facilities use standard Experiment Containers, mounted on two centrifuge rotors providing either microgravity or variable g-levels up to 2xg. Transparent covers allow illumination and observation (also near-infrared) of the internal experiment hardware containing the plant specimen. Standard interface plates provide each container with power and data lines, gas supply (controlled CO2, O2 and water vapour concentration; ethylene removal), and -for MCS only- connectors to water reservoirs. Besides the two concepts of environmental control in both facilities, there is a difference in container size (BIOLAB 0.36 1, height with respect to the g-vector 60 mm; MCS 0.58 1, height 160 mm) and in the degree of automation. The design of BIOLAB and MCS will be complimentary to NASA's Plant Research Unit (volume 20 1, height 380 mm) and should allow continuation of Space research on protoplasts, callus cultures, algae, fungi and seedlings, as earlier flown on Biorack, and new experiments with larger specimens of fungi, mosses and vascular plants.