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The thoughts of computer scientists at LeRC on the direction that computer development is taking and future implications are explored. Experts discuss the coming information superhighway and technologies such as fiber optics and neural networks. The impact of future computers on education, laboratory research, telecommunications, and science visualization.
This paper summarizes the results of several studies conducted at Langley Research Center over the past few years. The purposes of these studies were to investigate parameters of pictorial displays and imaging sensors that affect pilot approach and landing performance. Pictorial displays have demonstrated exceptional tracking performance and improved the pilots' spatial awareness. Stereopsis cueing improved pilot flight performance and reduced pilot stress. Sensor image parameters such as increased field-of-view. faster image update rate, and aiding symbology improved flare initiation. Finer image resolution and magnification improved attitude control performance parameters.
Integration of skills into an autonomous robot that performs a complex task is described. Time constraints prevented complete integration of all the described skills. The biggest problem was tuning the sensor-based region-finding algorithm to the environment involved. Since localization depended on matching regions found with the a priori map, the robot became lost very quickly. If the low level sensing of the world is not working, then high level reasoning or map making will be unsuccessful.
This report surveys different technologies and approaches to realize sensors for image warping. The goal is to study the feasibility, technical aspects, and limitations of making an electronic camera with special geometries which implements certain transformations for image warping. This work was inspired by the research done by Dr. Juday at NASA Johnson Space Center on image warping. The study has looked into different solid-state technologies to fabricate image sensors. It is found that among the available technologies, CMOS is preferred over CCD technology. CMOS provides more flexibility to design different functions into the sensor, is more widely available, and is a lower cost solution. By using an architecture with row and column decoders one has the added flexibility of addressing the pixels at random, or read out only part of the image.
Several years ago when INTEL and China Lake designed the ETANN chip, analog VLSI appeared to be the only way to do high density neural computing. In the last five years, however, digital parallel processing chips capable of performing neural computation functions have evolved to the point of rough equality with analog chips in system level computational density. The Naval Air Warfare Center, China Lake, has developed a real time, hardware and software system designed to implement and evaluate biologically inspired retinal and cortical models. The hardware is based on the Adaptive Solutions Inc. massively parallel CNAPS system COHO boards. Each COHO board is a standard size 6U VME card featuring 256 fixed point, RISC processors running at 20 MHz in a SIMD configuration. Each COHO board has a companion board built to support a real time VSB interface to an imaging seeker, a NTSC camera, and to other COHO boards. The system is designed to have multiple SIMD machines each performing different corticomorphic functions. The system level software has been developed which allows a high level description of corticomorphic structures to be translated into the native microcode of the CNAPS chips. Corticomorphic structures are those neural structures with a form similar to that of the retina, the lateral geniculate nucleus, or the visual cortex. This real time hardware system is designed to be shrunk into a volume compatible with air launched tactical missiles. Initial versions of the software and hardware have been completed and are in the early stages of integration with a missile seeker.
A flux transfer event recorded by the International Sun-Earth Explorers (ISEE) 1 and 2 spacecraft in the northern hemisphere near local noon is examined using analysis techniques developed recently for determination from single satellite magnetometer data of the orientation and cross-sectional shape of a two-dimensional disturbance moving along the magnetopause. The analysis is performed independently on the magnetic field data recorded by each satellite, enabling us to check the consistency of the results and thus to benchmark the method. The analysis is also extended to utilize the dual magnetometer measurements for determination of the event speed and size (which for a single spacecraft requires use of three-dimensional plasma velocity data to obtain a deHoffmann-Teller frame velocity) and for accommodating acceleration of the magnetopause normal to itself, which results in a curved spacecraft trajectory in the frame of reference moving with the disturbance. The analysis of the disturbance reveals that while its overall size is about 34,000 km in a direction parallel to the magnetopause but perpendicular to the event axis, the actual size of the bulge causing the field disturbance may have been as small as 9000 km with a dimension perpendicular to the magnetopause of the order of 1200 km. The bulge is found to be traveling at a speed of about 140 km/s toward the northern dawn quadrant of the dayside magnetopause. While plasma data from ISEE 2 provides evidence of plasma jetting, which suggests the event may be associated with reconnection, the orientation of the flux tube axis obtained from analysis is significantly different from the expected reconnection line direction. A discussion of possible interpretations of this bulge orientation and motion is provided.
Celestial visibility is the study of the limits of observability of objects in the sky, with application to deducing the truth about historical events or to the derivation of astronomical information of modern utility. This study is based on what is seen by ordinary humans, either in their everyday lives or at times of historical events. The results of such studies have more relevance to non-scientists than does any other area of astronomy. Celestial visibility is a young discipline in the sense that the number of interesting applications with simple solutions outnumber the solved problems; it is a broad interdisciplinary field that involves work with astronomy, meteorology, optics, physics, physiology, history, and archeology. Each of these disciplines contribute specialized mathematical formulations which quantify the many processes that affect light as it leaves a source, traverses the atmosphere, and is detected by the human eye. These formulas can then be combined as appropriate to create mathematical models for the visibility of the source under the conditions of interest. These model results can then be applied a wide variety of problems arising in history, astronomy, archeology, meteorological optics, and archeoastronomy. This review also presents a dozen suggestions for observing projects, many of which can be directly taken for individual study, for classroom projects, or for professional research.
The first published paper by a professional, research astronomer which discussed airborne astronomy from airplanes was by Paul W. Merrill. In it he proposed some of the types of observations which might be made, looking up at astronomical objects in the sky. This paper describes Merrill's paper, his education, training and subsequent career, and a few other aspects of the early history of airborne astronomy.
Miniature video cameras containing photoreceptors arranged in prescribed non-Cartesian patterns to compensate partly for some visual defects proposed. Cameras, accompanied by (and possibly integrated with) miniature head-mounted video display units restore some visual function in humans whose visual fields reduced by defects like retinitis pigmentosa.
This lecture discusses envisaged advanced concepts across the speed range including VTOL converticars (personal air transportation), advanced subsonic and supersonic long haul transports, hypersonic transports, and developments/applications of flow control technology. In most cases, these concepts and approaches offer at least the potential of 100 percent improvements in various performance metrics and, in some cases, far more. Special emphasis is given to advanced VTOL configurations which may offer simultaneous opportunities for mitigation of both drag-due-to-lift and wake vortex hazard and to synergistic propulsive and aerodynamic interactions. The lecture concludes that a virtual revolution in the civilian aeronautical world is conceivable as a result of technology maturation in several areas which could enable the exploitation of 'end-point' designs.
Substantial technical progress was made on all of the three high-risk subsystems of this program. The subsystems include dielectric antenna, G-band receiver, and electro-optic image processor. Progress is approximately on-schedule for both the receiver and the electro-optic processor development, while greater than anticipated challenges have been discovered in the dielectric antenna development. Much of the information in this report was covered in greater detail in the One-Year Review Meeting held at TTC on 22 February 1996. The performance goals of the dielectric antenna project are: Scan Angle -- 20 deg. desired; Loss -- 6 dB end to end (3 dB average); Frequency -- 206-218 GHz (6% bandwidth); Beam width -- 0.25 deg.; and Length -- 12 inches. The scan angle requirement was chosen to satisfy the needs of aircraft pilots. This requirement, coupled with the presently limited bandwidth processors (1 GHz state-of-the-art and 12 GHz in development in this program) forces the antenna to be dielectric (high scan angle air-filled waveguide-based antennas would be too lossy and their performance would vary too much as a function of frequency). A high dielectric constant (e.g., 10) was initially chosen for the dielectric material. This choice lead to the following fabrication challenges: total thickness variation (TTV) tolerance is 1 micrometer; coupler spacing tolerance is 1 micrometer; width tolerance is larger, but unknown, and the surfaces must have mirror finish. Also of importance is the difficulty in obtaining raw materials that satisfy the overall length requirement of 12 inches while simultaneously satisfying the above specifications.
Public support and enthusiasm for astronomy have been strong in the final decades of the twentieth century. Nowhere is this better demonstrated than with the Hubble Space Telescope (HCT), a grand endeavor, which is enabling astronomers to make giant strides in understanding our universe, our place in it, and our relation to it. The NASAs first infrared observatory, the Space Infrared Telescope Facility (SIRTF), promises to take the crucial next steps towards understanding the formation of stars and galaxies. Toward their completion, the HST and Beyond Committee identifies major goals, whose accomplishment will justify a commitment well into the next century: (1) the detailed study of the birth and evolution of normal galaxies such as the Milky Way; (2) the detection of Earth-like planets around other stars and the search for evidence of life on them; (3) NASA should develop a space observatory of aperture 4m or larger, optimized for imaging and spectroscopy over the wavelength range 1-5 microns; and (4) NASA should develop the capability for space interferometry.
This paper includes geoscience and remote sensing.
This paper includes geoscience and remote sensing.
A laser-directed ranging system for use in telerobotics applications and other applications involving physically handicapped individuals. The ranging system includes a left and right video camera mounted on a camera platform, and a remotely positioned operator. The position of the camera platform is controlled by three servo motors to orient the roll axis, pitch axis and yaw axis of the video cameras, based upon an operator input such as head motion. A laser is provided between the left and right video camera and is directed by the user to point to a target device. The images produced by the left and right video cameras are processed to eliminate all background images except for the spot created by the laser. This processing is performed by creating a digital image of the target prior to illumination by the laser, and then eliminating common pixels from the subsequent digital image which includes the laser spot. The horizontal disparity between the two processed images is calculated for use in a stereometric ranging analysis from which range is determined.
The NASA/NOAA/AMS Earth Science Electronic Theater presents Earth science observations and visualizations in a historical perspective. Fly in from outer space to the Delaware Bay and Philadelphia area. Go back to the early weather satellite images from the 1960s see them contrasted with the latest International global satellite weather movies including killer tropical cyclones & tornadic thunderstorms. See the latest spectacular images from NASA, NOAA & UMETSAT remote sensing missions like GOES, Meteosat, NOAA, TRMM, SeaWiFS, Landsat7, & new Terra which will be visualized with state-of-the art tools. Shown in High Definition TV resolution (2048 x 768 pixels) are visualizations of hurricanes Lenny, Floyd, Georges, Mitch, Fran and Linda. see visualizations featured on covers of magazines like Newsweek, TIME, National Geographic, Popular Science and on National & International Network TV. New Digital Earth visualization tools allow us to roam & zoom through massive global images including Landsat tours of the US, and Africa with drill downs of major global cities using 1 m resolution commercialized spy-satellite technology from the Space Imaging IKONOS satellite. Spectacular new visualizations of the global atmosphere & oceans are shown. See massive dust storms sweeping across Africa. see ocean vortexes and currents that bring up the nutrients to feed tiny plankton and draw the fish, giant whales and fisherman. See the how the ocean blooms in response to these currents and El Nino/La Nina climate changes. The demonstration is interactively driven by a SGI Octane Graphics Supercomputer with dual CPUs, 5 Gigabytes of RAM and Terabyte disk using two projectors across a super sized panoramic screen.
We present an algorithm for detecting a specified set of targets for an Automatic Target Recognition (ATR) application. ATR involves processing images for detecting, classifying, and tracking targets embedded in a background scene. We address the problem of discriminating between targets and nontarget objects in a scene by evaluating 40x40 image blocks belonging to an image. Each image block is first projected onto a set of templates specifically designed to separate images of targets embedded in a typical background scene from those background images without targets. These filters are found using directed principal component analysis which maximally separates the two groups. The projected images are then clustered into one of n classes based on a minimum distance to a set of n cluster prototypes. These cluster prototypes have previously been identified using a modified clustering algorithm based on prior sensed data. Each projected image pattern is then fed into the associated cluster's trained neural network for classification. A detailed description of our algorithm will be given in this paper. We outline our methodology for designing the templates, describe our modified clustering algorithm, and provide details on the neural network classifiers. Evaluation of the overall algorithm demonstrates that our detection rates approach 96% with a false positive rate of less than 0.03%.
The NASA/NOAA/AMS Earth Science Electronic Theater presents Earth science observations and visualizations in a historical perspective. Fly in from outer space to Florida and the KSC Visitor's Center. Go back to the early weather satellite images from the 1960s see them contrasted with the latest International global satellite weather movies including killer hurricanes & tornadic thunderstorms. See the latest spectacular images from NASA and NOAA remote sensing missions like GOES, NOAA, TRMM, SeaWiFS, Landsat7, & new Terra which will be visualized with state-of-the art tools. Shown in High Definition TV resolution (2048 x 768 pixels) are visualizations of hurricanes Lenny, Floyd, Georges, Mitch, Fran and Linda. See visualizations featured on covers of ma'gazines like Newsweek, TIME, National Geographic, Popular Science and on National & International Network TV. New Digital Earth visualization tools allow us to roam & zoom through massive global images including a Landsat tour of the US, with drill-downs into major cities using 1 m resolution spy-satellite technology from the Space Imaging IKONOS satellite. Spectacular new visualizations of the global atmosphere & oceans are shown. See massive dust storms sweeping across Africa. See ocean vortexes and currents that bring up the nutrients to feed tiny plankton and draw the fish, giant whales and fisherman. See the how the ocean blooms in response to these currents and El Nino/La Nina climate changes. The demonstration is interactively driven by a SGI Octane Graphics Supercomputer with dual CPUS, 5 Gigabytes of RAM and Terabyte disk using two projectors across the super sized Universe Theater panoramic screen.