Search NASA⌕ Search

SEARCH · Search NASA

Results for “Imaging & optical processing”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 109 records · Page 6

Demonstration of automated proximity and docking technologies

An autodock was demonstrated using straightforward techniques and real sensor hardware. A simulation testbed was established and validated. The sensor design was refined with improved optical performance and image processing noise mitigation techniques, and the sensor is ready for production from off-the-shelf components. The autonomous spacecraft architecture is defined. The areas of sensors, docking hardware, propulsion, and avionics are included in the design. The Guidance Navigation and Control architecture and requirements are developed. Modular structures suitable for automated control are used. The spacecraft system manager functions including configuration, resource, and redundancy management are defined. The requirements for autonomous spacecraft executive are defined. High level decisionmaking, mission planning, and mission contingency recovery are a part of this. The next step is to do flight demonstrations. After the presentation the following question was asked. How do you define validation? There are two components to validation definition: software simulation with formal and vigorous validation, and hardware and facility performance validated with respect to software already validated against analytical profile.

Anderson, Robert L.↗

A hybrid six degree-of-freedom tracking system

An optical/digital/mechanical six degree of freedom tracking system using an optical correlator for image processing is being constructed at NASA's Johnson Space Center. The degrees of freedom are expressed in sensor coordinates as azimuth, elevation, range, line-of-sight rotation, and the two out-of-plane object rotation angles. Hardware for an initial configuration has been assembled and various tracking algorithms and filtering techniques are being implemented and evaluated. The current correlator hardware is based on LCTV SLMs from a commercial television projector. Correlation peak detection and measurement are made using commercially available digital image processing boards. Out-of-plane object rotation, range, and line-of-sight rotation are tracked by various correlation filter techniques. Performance of the current system is presented, as are plans for future configurations.

Monroe, Stanley E., Jr.↗

Advances in Projection Moire Interferometry Development for Large Wind Tunnel Applications

An instrument development program aimed at using Projection Moire Interferometry (PMI) for acquiring model deformation measurements in large wind tunnels was begun at NASA Langley Research Center in 1996. Various improvements to the initial prototype PMI systems have been made throughout this development effort. This paper documents several of the most significant improvements to the optical hardware and image processing software, and addresses system implementation issues for large wind tunnel applications. The improvements have increased both measurement accuracy and instrument efficiency, promoting the routine use of PMI for model deformation measurements in production wind tunnel tests.

Fleming, Gary A.↗

R and D work on the constrained vapor bubble system for a microgravity experiment

We are working with Project Scientists R. Balasubramanian and Sang Young Son, and a NASA Projects Team headed by Sue Motil at the Glenn Research Center on the design and development of an experimental system for use on the International Space Station during the year 2006. John Eustace is the coordinator for the flight experiment at Zin-Tech (previously Northrop-Grumman) for the design and development of the Constrained Vapor Bubble Heat Exchanger, CVBHX, cell which will fit into the Light Microscope Module, LMM. Good progress is being made. The CDR for the LMM being developed was held on December 10-1 1,2003. Experimental results obtained under microgravity conditions will be compared with those obtained at Rensselaer. Basic and applied research at Rensselaer continues on the experimental and theoretical details associated with passive phase change heat transfer processes controlled by interfacial forces in the CVBHX. The extensive results of our current research are presented in the 23 external publications listed below. Twenty-two external presentations have been given. Briefly, evaporation/condensation data from both vertical and horizontal CVBHX systems were obtained and analyzed for both polar (wetting) and apolar (partially wetting) fluids. The vertical system is axi-symmetric, but strongly effected by gravity. Whereas, the horizontal system is asymmetric, but weakly effected by gravity. Therefore, there will be significant differences in the operation of the cell in the earth s environment versus the operation under microgravity conditions. Due to its relative large size, the system s performance should be optimum under micro-gravity conditions, where the CVBHX should be a very effective passive heat exchanger. The CVBHX was found to be an ideal experimental setup in which to study the effects of interfacial phenomena on both the evaporation and drop-wise condensation processes. The optical technique (Image Analyzing Interferometry, IAI), which is based on the measurement and analysis of the reflectivity pattern of a thin film, was significantly improved. The accuracy of the IAI system is of critical importance to the success of the mission because it is used to measure the details of the pressure field in the liquid by measuring the film thickness profile. The accuracy was found to be excellent and various publications/presentations documenting these new results were written. Significant new results were also obtained for the effect of the oscillating contact line region on evaporation. Three doctoral students graduated under this grant. All three work in US industry, two for Intel. Another doctoral student is in his third year of study and will finish under an extension of the NASA grant: # NNC05GA27G.

Wayner, P. C., Jr.↗

Toward the fabrication of a 5- μm -resolution Wolter microscope for the National Ignition Facility (invited)

Advancements in computer-controlled polishing, metrology, and replication have led to an x-ray mirror fabrication process that is capable of producing high-resolution Wolter microscopes. Here, we present the fabrication and test of a nickel–cobalt replicated full-shell x-ray mirror that was electroformed from a finely figured and polished mandrel. This mandrel was designed for an 8-m source-to-detector-distance microscope, with 10× magnification, and was optimized to reduce shell distortions that occur within 20 mm of the shell ends. This, in combination with an improved replication tooling design and refined bath parameters informed by a detailed COMSOL Multiphysics® model, has led to reductions in replication errors in the mirrors. Mandrel surface fabrication was improved by implementing a computer-controlled polishing process that corrected the low-frequency mandrel figure error and achieved <2.0 nm RMS convergence error. X-ray tests performed on a pair of mirror shells replicated from the mandrel have demonstrated <10 μm full-width at half-maximum (FWHM) spatial resolution. Here, we discuss the development process, highlight results from metrology and x-ray testing, and define a path for achieving a program goal of 5 μm FWHM resolution.

47 OTHER INSTRUMENTATION↗

Design concepts for an on-board coherent optical image processor

On-board spacecraft image data processing systems for transmitting processed data rather than raw data are discussed. A brief history of the development of the optical data processing techniques is presented along with the conceptual design of a coherent optical system with a noncoherent image input.

Husain-Abidi, A. S.↗

Optical correlator method and apparatus for particle image velocimetry processing

Young's fringes are produced from a double exposure image of particles in a flowing fluid by passing laser light through the film and projecting the light onto a screen. A video camera receives the image from the screen and controls a spatial light modulator. The spatial modulator has a two dimensional array of cells the transmissiveness of which are controlled in relation to the brightness of the corresponding pixel of the video camera image of the screen. A collimated beam of laser light is passed through the spatial light modulator to produce a diffraction pattern which is focused onto another video camera, with the output of the camera being digitized and provided to a microcomputer. The diffraction pattern formed when the laser light is passed through the spatial light modulator and is focused to a point corresponds to the two dimensional Fourier transform of the Young's fringe pattern projected onto the screen. The data obtained fro This invention was made with U.S. Government support awarded by the Department of the Army (DOD) and NASA grand number(s): DOD #DAAL03-86-K0174 and NASA #NAG3-718. The U.S. Government has certain rights in this invention.

Farrell, Patrick V.↗

A model for radar images and its application to adaptive digital filtering of multiplicative noise

Standard image processing techniques which are used to enhance noncoherent optically produced images are not applicable to radar images due to the coherent nature of the radar imaging process. A model for the radar imaging process is derived in this paper and a method for smoothing noisy radar images is also presented. The imaging model shows that the radar image is corrupted by multiplicative noise. The model leads to the functional form of an optimum (minimum MSE) filter for smoothing radar images. By using locally estimated parameter values the filter is made adaptive so that it provides minimum MSE estimates inside homogeneous areas of an image while preserving the edge structure. It is shown that the filter can be easily implemented in the spatial domain and is computationally efficient. The performance of the adaptive filter is compared (qualitatively and quantitatively) with several standard filters using real and simulated radar images.

Frost, V. S.↗

DMTN-197: Streak Masking in DM Image Processing

Streaks caused by satellites are a persistent problem in optical images, and their occurrence will likely increase in the coming years. Many Hyper Suprime-Cam images are already affected by streaks, and the same is expected for Rubin Observatory data. In the LSST Data Release Production (DRP), most streaks and other artifacts are already detected and masked by the algorithm CompareWarpAssembleCoadd. However, some streaks are not caught at this stage and can contaminate the final coadds and detection catalogs. To find and mask these, we adopt a morphologically-based method for detecting streaks, which uses the Kernel-Based Hough Transform to detect straight lines. Once the lines are detected, the streak profile is fit and the affected portion of the image is masked out. This algorithm, maskStreaks, is included in the meas_algorithms package and is used in CompareWarpAssembleCoadd to remove streaks from coadds. Similar implementation in the Alert Production Pipeline is possible but has not been implemented.

79 ASTRONOMY AND ASTROPHYSICS↗

The Apollo 17 Lunar Sounder

The Apollo Lunar Sounder Experiment, a coherent radar operated from lunar orbit during the Apollo 17 mission, has scientific objectives of mapping lunar subsurface structure, surface profiling, surface imaging, and galactic noise measurement. Representative results from each of the four disciplines are presented. Subsurface reflections have been interpreted in both optically and digitally processed data. Images and profiles yield detailed selenomorphological information. The preliminary galactic noise results are consistent with earlier measurements by other workers.

Phillips, R. J.↗

Independent Optical Navigation Processing for the Osiris-Rex Mission Using the Goddard Image Analysis and Navigation Tool

The OSIRIS-REx mission to the asteroid(101955) Bennu heavily relies on optical navigation to provide relative state information between the asteroid and the spacecraft. These measurements enable determination of the spacecraft's orbit to the tight requirements needed to meet the science goals of the mission. In this document we describe the algorithms and techniques used by the Goddard independent verification and validation navigation effort to extract these measurements from the images taken by the spacecraft during the mission.We also demonstrate the capabilities of the techniques by showing the high accuracy of the results when used in an orbit determination solution.

Liounis, Andrew↗

Topology-imprinting in nonlinear metasurfaces

Flat optical components, or metasurfaces, have transformed optical imaging, data storage, information processing, and biomedical applications by providing unprecedented control over light-matter interactions. These nano-engineered structures enable compact, multidimensional manipulation of light’s amplitude, phase, polarization, and wavefront, producing scalar and vector beams with unique properties such as orbital angular momentum and knotted topologies. This flexibility has potential applications in optical communication and imaging, particularly in complex environments such as atmospheric turbulence and undersea scattering. However, designing metasurfaces for shorter wavelengths, such as visible and ultraviolet light, remains challenging due to fabrication limitations and material absorption. Here, we introduce an innovative concept called topology imprinting using judiciously designed all-dielectric nonlinear optical metasurfaces to replicate desired waveforms at fundamental and harmonic frequencies, opening promising avenues for advanced photonic applications.

42 ENGINEERING↗

Experimental Modal Analysis Using Phase Quantities from Phase-Based Motion Processing and Motion Magnification

Phase-based motion processing and the associated Motion Magnification that it enables has become popular not only for the striking videos that it can produce of traditionally stiff structures visualized with very large deflections, but also for its ability to pull information out of the noise floor of images so that they can be processed with more traditional optical techniques such as digital image correlation or feature tracking. While the majority of papers in the literature have utilized the Phase-based Image Processing approach as a pre-processor for more quantitative analyses, the technique itself can be used directly to extract modal parameters from an image, noting that the extracted phases are proportional to displacements in the image. Therefore, once phases are extracted, they can be fit using traditional experimental modal analysis techniques. This produces a mode “shape” where the degrees of freedom are phases instead of physical motions. These phases can be scaled to produce on-image visualizations of the mode shapes, rather than operational shapes produced by bandpass filtering. Modal filtering techniques can also be used to visualize motions from an environment on an image using the modal phases as a basis for the expansion.

47 OTHER INSTRUMENTATION↗

Image-plane processing of visual information

Shannon's theory of information is used to optimize the optical design of sensor-array imaging systems which use neighborhood image-plane signal processing for enhancing edges and compressing dynamic range during image formation. The resultant edge-enhancement, or band-pass-filter, response is found to be very similar to that of human vision. Comparisons of traits in human vision with results from information theory suggest that: (1) Image-plane processing, like preprocessing in human vision, can improve visual information acquisition for pattern recognition when resolving power, sensitivity, and dynamic range are constrained. Improvements include reduced sensitivity to changes in lighter levels, reduced signal dynamic range, reduced data transmission and processing, and reduced aliasing and photosensor noise degradation. (2) Information content can be an appropriate figure of merit for optimizing the optical design of imaging systems when visual information is acquired for pattern recognition. The design trade-offs involve spatial response, sensitivity, and sampling interval.

Huck, F. O.↗

Optical navigation for the Galileo Gaspra encounter

The optical navigation process as practiced during the Gaspra encounter is presented. The characteristics of image formation for a single-frame mosaic picture required the development of a new image processing algorithm to extract the optical measurements. A detailed formulation of this algorithm is presented along with the results of applying it to the pictures returned from the spacecraft.

Vaughan, R. M.↗

NASA spinoffs to bioengineering and medicine

Through the active transfer of technology, the National Aeronautics and Space Administration (NASA) Technology Utilization (TU) Program assists private companies, associations, and government agencies to make effective use of NASA's technological resources to improve U.S. economic competitiveness and to provide societal benefit. Aerospace technology from areas such as digital image processing, space medicine and biology, microelectronics, optics and electrooptics, and ultrasonic imaging have found many secondary applications in medicine. Examples of technology spinoffs are briefly discussed to illustrate the benefits realized through adaptation of aerospace technology to solve health care problems. Successful implementation of new technologies increasingly requires the collaboration of industry, universities, and government, and the TU Program serves as the liaison to establish such collaborations with NASA. NASA technology is an important resource to support the development of new medical products and techniques that will further advance the quality of health care available in the U.S. and worldwide.

Biomedical Engineering/instrumentation/trends↗

Proof of principle study: synchrotron X-ray fluorescence microscopy for identification of previously radioactive microparticles and elemental mapping of FFPE tissues

Biobanks containing formalin-fixed, paraffin-embedded (FFPE) tissues from animals and human atomic-bomb survivors exposed to radioactive particulates remain a vital resource for understanding the molecular effects of radiation exposure. These samples are often decades old and prepared using harsh fixation processes which limit sample imaging options. Optical imaging of hematoxylin and eosin (H&E) stained tissues may be the only feasible processing option, however, H&E images provide no information about radioactive microparticles or radioactive history. Synchrotron X-ray fluorescence microscopy (XFM) is a robust, non-destructive, semi-quantitative technique for elemental mapping and identifying candidate chemical element biomarkers in FFPE tissues. Still, XFM has never been used to uncover distribution of formerly radioactive micro-particulates in FFPE canine specimens collected more than 30 years ago. In this work, we demonstrate the first use of low-, medium-, and high-resolution XFM to generate 2D elemental maps of ~ 35-year-old, canine FFPE lung and lymph node specimens stored in the Northwestern University Radiobiology Archive documenting distribution of formerly radioactive micro-particulates. Additionally, we use XFM to identify individual microparticles and detect daughter products of radioactive decay. The results of this proof-of-principle study support the use of XFM to map chemical element composition in historic FFPE specimens and conduct radioactive micro-particulate forensics.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Multiresponse Imaging For Improved Resolution

Images restored with resolution finer than sampling lattice. Multiresponse imaging overcomes sampling-passband constraint and critically constrained only by optical response and sensitivity of image-gathering device. Process consists of multiresponse image gathering and Wiener-matrix restoration. Image-gathering process acquires sequence of images, each with different optical response so within-pass-band and aliased signal components weighted differently. Wiener-matrix filter, in turn, unscrambles within-passband and aliased frequency components of undersampled signal and restores them up to cutoff frequency of optical response.

Fales, Carl L., Jr.↗