Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “Video”

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 163 records · Page 9

Registration of video sequences from multiple sensors

In this paper, we describe an approach for registration of video sequences from a suite of multiple sensors including television, infrared and radar. Video sequences generated by these sensors may contain abrupt changes in local contrast and inconsistent image features, which pose additional difficulties for registration. Our approach to registration addresses the difficulties caused by using multiple sensors. We use a representation for registration that is invariant to local contrast changes, followed by smoothing of the resulting error measure used for registration, for robust estimation of registration parameters. We use an iterative procedure to reduce the effect of inconsistent features. Finally, we describe a method that uses same-sensor registration to aide in performing registration of sequences of video frames across multiple sensors.

Sharma, Ravi K.↗

Video Guidance Sensor: Optical Performance Predictions and Results from STS-95 Experiment

The Video Guidance Sensor is a key component of NASA's Automated Rendezvous & Capture Program. The Video Guidance Sensor Uses laser illumination of a passive target in the field of view of an on-board camera and signal processor to determine the relative position and attitude between the target and sensor. The Video Guidance Sensor flew on space shuttle mission STS-95 in November of 1998 and was a marked success. Comparisons of experimental results from that mission and theoretical models predicting the optical performance will be discussed.

Jackson, John L.↗

The Video Guidance Sensor- A Flight Proven Technology

The Video Guidance Sensor (VGS) flew on Shuttle mission STS-95 in October of 1998 to test the VGS functional characteristics on orbit. This was the second flight of the VGS, and during these two flights, both long range and short range data were gathered under a variety of lighting conditions, orbital exposure times, and temperatures. The flight experiment sensor was designed to operate from 1.5 meter range out to 110 meter range, with a field-of-view of 16 X 21 degrees. The VGS tracked its target at a 5 Hz rate and returned 6-degree-of-freedom information on the target's position and attitude relative to the sensor. The VGS was mounted in the Shuttle cargo bay, and its target was mounted on the Spartan spacecraft being carried on this mission. The VGS is a sensor designed to allow an automated vehicle to dock with a spacecraft equipped with a passive target. The VGS is a part of an Automated Rendezvous and Capture (AR&C) system being developed and tested by NASA. The orbital testing included operations with the target on the Shuttle's Remote Manipulator System (RMS) near the start of each flight of the VGS, long-range data (on the STS-95 flight) during the Shuttle rendezvous with the Spartan two days later, and some more RMS operations later in the mission. The data returned from the orbital testing included VGS diagnostics, acquisition, and tracking data, RMS positions, hand-held laser range data, tapes of the data from the VGS video camera, and orbital positioning data from the Spartan and the Shuttle to allow correlation of the VGS data with orbital best-estimate-of-truth data. The Video Guidance Sensor performed well in all phases of the testing, and the VGS is being incorporated into the ground testing of a complete automated rendezvous and docking system. Work on the development of the next generation VGS is continuing.

Howard, Richard T.↗

On Orbit Testing of the Video Guidance Sensor

The Video Guidance Sensor (VGS), part of NASA's Automated Rendezvous and Capture program, was flown on Shuttle mission STS-95 in October of 1998 to orbitally test the functional characteristics of the VGS. This was the second flight of the VGS (the first flight was in 1997 on STS-87), and this time long-range tracking data was gathered during the experiment. The flight experiment sensor was designed to operate from 1.5 meter range out to 110 meter range, with a field-of-view of 16 X 21 degrees. The VGS tracked its target at a 5 Hz rate and returned 6-degree-of-freedom information on the target's position and attitude relative to the sensor. The VGS was mounted in the Shuttle cargo bay, and its target was mounted on the Spartan spacecraft being carried on this mission. The orbital testing of the VGS included operations with the target on the Shuttle's Remote Manipulator System (RMS) at the start of the 10-day mission, long-range data during the Shuttle rendezvous with the Spartan two days later, and some more RMS operations later in the mission. The data returned from the orbital testing included VGS diagnostics, acquisition, and tracking data, RMS positions, hand-held laser range data, tapes of the data from the VGS video camera, and orbital positioning data from the Spartan and the Shuttle to allow correlation of the VGS data with orbital best-estimate-of-truth data. The Video Guidance Sensor performed well in all phases of the testing, and the VGS is being incorporated into the ground testing of a complete automated rendezvous and docking system. Work on the development of the next generation VGS is continuing

Howard, Richard T.↗

Video Imaging System Particularly Suited for Dynamic Gear Inspection

A digital video imaging system that captures the image of a single tooth of interest of a rotating gear is disclosed. The video imaging system detects the complete rotation of the gear and divide that rotation into discrete time intervals so that each tooth of interest of the gear is precisely determined when it is at a desired location that is illuminated in unison with a digital video camera so as to record a single digital image for each tooth. The digital images are available to provide instantaneous analysis of the tooth of interest, or to be stored and later provide images that yield a history that may be used to predict gear failure, such as gear fatigue. The imaging system is completely automated by a controlling program so that it may run for several days acquiring images without supervision from the user.

Broughton, Howard↗

The Video Guidance Sensor: Space, Earth, Ground, and Sea

Engineers at the Marshall Space Flight Center (MSFC) have been developing and testing video-based sensors for automated spacecraft guidance for several years. The next generation of Video Guidance Sensor (VGS) is being designed to be faster and more capable than ever. It will have applications to relative position measurement in any field of endeavor. The system works by sequentially firing two different wavelengths of laser diodes at the target (which has retroreflectors) and processing the two images. Since the target only reflects one wavelength, it shows up well in one image and not at all in the other. Because the target's dimensions are known, the relative positions and attitudes of the target and the sensor can be computed from the spots reflected from the target. The current sensor operates at 5 Hz at ranges from 1 to 110 meters with a 20 deg. field-of-view. The Video Guidance Sensor (VGS) developed over the past several years has performed well in testing and met the objective of being used as the terminal guidance sensor for an automated rendezvous and capture system. The first VGS was successfully tested in closed-loop 3-degree-of-freedom (3-DOF) tests in 1989 and then in 6-DOF open-loop tests in 1992 and closed-loop tests in 1993-4. Development and testing continued, and in 1995 approval was given to test the VGS in an experiment on the Space Shuttle. The VGS flew in 1997 and in 1998, performing well during both flight experiments. During the development and testing before, during, and after the flight experiments, numerous areas for improvement were found. The next generation of VGS is being designed to operate at up to 100 Hz tracking rates and at ranges from 0.5 to 200 meters. In addition to its use as a spacecraft guidance sensor, it could be used as an alignment aid for an operator of a remote system (giving position and attitude feedback data), as a feedback system for a robotic arm, or for automated vehicle guidance. The next generation VGS, with its higher tracking rates, smaller size, and lower power could be used in more places than the original VGS, and by using LED's instead of laser diodes, the system would be eye-safe at any range. More potential applications include aerial station keeping (keeping 2 or more autonomous aircraft within particular relative positions), under-water robotics, and the guidance of ground vehicles in predefined areas equipped with sets of targets.

Howard, Richard T.↗

STS-92 Preflight Briefings Video Feed and International Space Station Overview

The first half of this video is a collection of video feeds from various preflight conferences and simulations show the payload bay and payload equipment. The International Space Station's (ISS) structure is seen, as are close-up shots of the Z-1 truss. Footage shows extravehicular activity (EVA) underwater training. The second half of the video is a preflight conference on the mission objectives concerning the ISS. Tommy Halloway, Manager, ISS Program, and Robert Cabana, ISS Manager for International Operations, discuss the STS-92 mission in terms of the ISS and the role of ISS in the future. Mr. Cabana gives the status of present and future ISS hardware. The men then answer questions from the press.

Source record↗

Video Golf

George Nauck of ENCORE!!! invented and markets the Advanced Range Performance (ARPM) Video Golf System for measuring the result of a golf swing. After Nauck requested their assistance, Marshall Space Flight Center scientists suggested video and image processing/computing technology, and provided leads on commercial companies that dealt with the pertinent technologies. Nauck contracted with Applied Research Inc. to develop a prototype. The system employs an elevated camera, which sits behind the tee and follows the flight of the ball down range, catching the point of impact and subsequent roll. Instant replay of the video on a PC monitor at the tee allows measurement of the carry and roll. The unit measures distance and deviation from the target line, as well as distance from the target when one is selected. The information serves as an immediate basis for making adjustments or as a record of skill level progress for golfers.

Source record↗

Method and Apparatus for Evaluating the Visual Quality of Processed Digital Video Sequences

A Digital Video Quality (DVQ) apparatus and method that incorporate a model of human visual sensitivity to predict the visibility of artifacts. The DVQ method and apparatus are used for the evaluation of the visual quality of processed digital video sequences and for adaptively controlling the bit rate of the processed digital video sequences without compromising the visual quality. The DVQ apparatus minimizes the required amount of memory and computation. The input to the DVQ apparatus is a pair of color image sequences: an original (R) non-compressed sequence, and a processed (T) sequence. Both sequences (R) and (T) are sampled, cropped, and subjected to color transformations. The sequences are then subjected to blocking and discrete cosine transformation, and the results are transformed to local contrast. The next step is a time filtering operation which implements the human sensitivity to different time frequencies. The results are converted to threshold units by dividing each discrete cosine transform coefficient by its respective visual threshold. At the next stage the two sequences are subtracted to produce an error sequence. The error sequence is subjected to a contrast masking operation, which also depends upon the reference sequence (R). The masked errors can be pooled in various ways to illustrate the perceptual error over various dimensions, and the pooled error can be converted to a visual quality measure.

Watson, Andrew B.↗

NASA Video Catalog

This issue of the NASA Video Catalog cites video productions listed in the NASA STI Database. The videos listed have been developed by the NASA centers, covering Shuttle mission press conferences; fly-bys of planets; aircraft design, testing and performance; environmental pollution; lunar and planetary exploration; and many other categories related to manned and unmanned space exploration. Each entry in the publication consists of a standard bibliographic citation accompanied by an abstract. The Table of Contents shows how the entries are arranged by divisions and categories according to the NASA Scope and Coverage Category Guide. For users with specific information, a Title Index is available. A Subject Term Index, based on the NASA Thesaurus, is also included. Guidelines for usage of NASA audio/visual material, ordering information, and order forms are also available.

Source record↗

Recent Advances in Video Meteor Photometry

One of the most common (and obvious) problems with video meteor data involves the saturation of the output signal produced by bright meteors, resulting in the elimination of such meteors from photometric determinations. It is important to realize that a "bright" meteor recorded by intensified meteor camera is not what would be considered "bright" by a visual observer - indeed, many Generation II or III camera systems are saturated by meteors with a visual magnitude of 3, barely even noticeable to the untrained eye. As the relatively small fields of view (approx.30 ) of the camera systems captures at best modest numbers of meteors, even during storm peaks, the loss of meteors brighter than +3 renders the determination of shower population indices from video observations even more difficult. Considerable effort has been devoted by the authors to the study of the meteor camera systems employed during the Marshall Space Flight Center s Leonid ground-based campaigns, and a calibration scheme has been devised which can extend the useful dynamic range of such systems by approximately 4 magnitudes. The calibration setup involves only simple equipment, available to amateur and professional, and it is hoped that use of this technique will make for better meteor photometry, and move video meteor analysis beyond the realm of simple counts.

Swift, Wesley R.↗

NASA Video Catalog

This issue of the NASA Video Catalog cites video productions listed in the NASA STI Database. The videos listed have been developed by the NASA centers, covering Shuttle mission press conferences; fly-bys of planets; aircraft design, testing and performance; environmental pollution; lunar and planetary exploration; and many other categories related to manned and unmanned space exploration. Each entry in the publication consists of a standard bibliographic citation accompanied by an abstract. The Table of Contents shows how the entries are arranged by divisions and categories according to the NASA Scope and Coverage Category Guide. For users with specific information, a Title Index is available. A Subject Term Index, based on the NASA Thesaurus, is also included. Guidelines for usage of NASA audio/visual material, ordering information, and order forms are also available.

Source record↗

A Digital Video Model Deformation System

The use of slid-state array cameras and a PC controlled image acquisition system to measure model deformation in a wind tunnel is discussed. This digital system is an improvement to an earlier video model deformation system used at the National Transonic Facility (NTF) which employed high-resolution tube cameras and required the manual measurement of targets on video hardcopy images. The new system eliminates both the vibration-induced distortion associated with tube cameras and the manual readup of video images necessary in the earlier version. Camera calibration and data reduction procedures necessary to convert pixel image plane data from two cameras into wing deflections are presented. Laboratory tests to establish the uncertainty of the new system with the geometry to be used at the NTF are described.

Burner, A. W.↗

Close-Range Photogrammetry with Video Cameras

Examples of photogrammetric measurements made with video cameras uncorrected for electronic and optical lens distortions are presented. The measurement and correction of electronic distortions of video cameras using both bilinear and polynomial interpolation are discussed. Examples showing the relative stability of electronic distortions over long periods of time are presented. Having corrected for electronic distortion, the data are further corrected for lens distortion using the plumb line method. Examples of close-range photogrammetric data taken with video cameras corrected for both electronic and optical lens distortion are presented.

Burner, A. W.↗

From Video to Photo

Ever wonder whether a still shot from a home video could serve as a "picture perfect" photograph worthy of being framed and proudly displayed on the mantle? Wonder no more. A critical imaging code used to enhance video footage taken from spaceborne imaging instruments is now available within a portable photography tool capable of producing an optimized, high-resolution image from multiple video frames.

Source record↗

NASA Video Catalog

This issue of the NASA Video Catalog cites video productions listed in the NASA STI Database. The videos listed have been developed by the NASA centers, covering Shuttle mission press conferences; fly-bys of planets; aircraft design, testing and performance; environmental pollution; lunar and planetary exploration; and many other categories related to manned and unmanned space exploration. Each entry in the publication consists of a standard bibliographic citation accompanied by an abstract. The Table of Contents shows how the entries are arranged by divisions and categories according to the NASA Scope and Coverage Category Guide. For users with specific information, a Title Index is available. A Subject Term Index, based on the NASA Thesaurus, is also included. Guidelines for usage of NASA audio/visual material, ordering information, and order forms are also available.

Source record↗

NASA Video Catalog

This issue of the NASA Video Catalog cites video productions listed in the NASA STI database. The videos listed have been developed by the NASA centers, covering Shuttle mission press conferences; fly-bys of planets; aircraft design, testing and performance; environmental pollution; lunar and planetary exploration; and many other categories related to manned and unmanned space exploration. Each entry in the publication consists of a standard bibliographic citation accompanied by an abstract. The Table of Contents shows how the entries are arranged by divisions and categories according to the NASA Scope and Subject Category Guide. For users with specific information, a Title Index is available. A Subject Term Index, based on the NASA Thesaurus, is also included. Guidelines for usage of NASA audio/visual material, ordering information, and order forms are also available.

Source record↗

Multiplying video mixer system

A multiplying video mixer system including a digital signal generator for generating at least one overlay signal and an attribute control bit corresponding to each of a plurality of pixels. A background signal generator generates input background signals to which the attribute control bits are applied to effect the input background signals with a desired opaque/transparent attribute. At least one video multiplier multiplies the overlay attribute signals and background signals to produce an output video signal having an amplitude equal to the product of the amplitudes of the overlay and background signals.

Heckt, Neil W.↗