Browse Topic: Charge coupled devices

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Robust Sensor Fused Object Detection Using Convolutional Neural Networks for Autonomous Vehicles2020-01-01004/14/2020
Environmental perception is considered an essential module for autonomous driving and Advanced Driver Assistance System (ADAS). Recently, deep Convolutional Neural Networks (CNNs) have become the State-of-the-Art with many different architectures in various object detection problems. However, performances of existing CNNs have been dropping when detecting small objects at a large distance. To deploy any environmental perception system in real world applications, it is important that the system achieves high accuracy regardless of the size of the object, distance, and weather conditions. In this paper, a robust sensor fused object detection system is proposed by utilizing the advantages of both vision and automotive radar sensors. The proposed system consists of three major components: 1) the Coordinate Conversion module, 2) Multi level-Sensor Fusion Detection (MSFD) system, and 3) Temporal Correlation filtering module. The proposed MSFD system employs the principles of artificial intelligence beyond simple comparison of data variance of the sensors. And then, its performance is further improved by using the temporal correlation information with an adaptive threshold scheme. The proposed system is evaluated with the collected video data (6,854 image frames with 18,918 labeled objects). Based on the laboratory testing and in-vehicle validation, the proposed system demonstrates its high accuracy for detecting any size of objects in real-world data.
Park, Jungme, Jayachandran Raguraman, Sriram, Aslam, Aakif, Gotadki, Shruti
Decoding Multiple Frames from a Single, Scattered ExposureTBMG-348908/1/2019
When light gets scattered as it passes through a translucent material, the emerging pattern of “speckle” looks as random as static on a television screen with no signal. But it isn't random. Because the light coming from one point of an object travels a path very similar to that of the light coming from an adjacent point, the speckle pattern from each looks very much the same, just shifted slightly. Because modern cameras can record hundreds of millions of pixels at a time, only a single exposure is needed to make the statistics work.
Decoding Multiple Frames From a Single Scattered ExposureTBMG-335521/1/2019
Engineers at Duke University have developed a way to extract a sequence of images from light scattered through a mostly opaque material — or even off a wall — from one long photographic exposure. The technique has applications in a wide range of fields from security to healthcare to astronomy.
High Energy Computed Tomographic Inspection of MunitionsTBMG-269956/1/2017
An advance computed tomography (CT) system was recently built for the U.S. Army Armament Research, Development and Engineering Center, Picatinny Arsenal, NJ, for the inspection of munitions. The system is a charged coupled device (CCD) camera based CT system designated with the name “experimental Imaging Media” (XIM). The design incorporated shielding for use up to 4MeV x-ray photons and integrated two separate cameras into one single field of view (FOV). Other major distinguishing characteristics include its processing functions to digitally piece the two cameras together, use of advanced artifact reduction principles, performing reconstruction simultaneously during acquisition, and its development in accurate beam hardening corrections through digital means.
High Energy Computed Tomographic Inspection of Munitions17AERP06_086/1/2017
Inspection system provides additional level of quality assurance for R&D, reverse engineering, and malfunction investigations. Armament Research, Development and Engineering Center, Picatinny Arsenal, New Jersey An advance computed tomography (CT) system was recently built for the U.S. Army Armament Research, Development and Engineering Center, Picatinny Arsenal, NJ, for the inspection of munitions. The system is a charged coupled device (CCD) camera based CT system designated with the name “eXperimental Imaging Media” (XIM). The design incorporated shielding for use up to 4MeV x-ray photons and integrated two separate cameras into one single field of view (FOV). Other major distinguishing characteristics include its processing functions to digitally piece the two cameras together, use of advanced artifact reduction principles, performing reconstruction simultaneously during acquisition, and its development in accurate beam hardening corrections through digital means. The overall setup of the system, as shown, depicts the internal layout of the cameras, shielding, scintillation screen, and rotational fixture. The general layout is comparative to a common 16-bit CCD camera radiographic imaging system. The x-ray photons pass through the inspection piece and impinge onto a scintillation/phosphor screen where the energy is converted into visible light. From there, the light is redirected off a series of mirrors that allow the cameras to be out of the direct line of sight of the main radiation beam. The light is then focused through the camera lens and into a cooled CCD chip.
Brooke Thornton, Mission Operations Manager, NASA’s Langley Research Center, Hampton, VATBMG-267664/24/2017
On February 19, The Stratospheric Aerosol and Gas Experiment (SAGE) III instrument launched aboard a cargo capsule to the International Space Station. SAGE III — equipped with a telescope, grating spectrometer, and charge coupled device detector array — will use the light from the Sun and Moon to provide a profile of the atmosphere, including the Earth’s ozone layer. The technology will launch aboard the Falcon Dragon 9, a rocket developed by the Hawthorne, CA-based SpaceX.
High-Quantum Efficiency Photocathodes for Medical DiagnosticsTBMG-264232/1/2017
Detection of a single photon is a requirement for many research and medical applications, such as fluorescence imaging, single molecule imaging, and luminescence applications. The sensitivity required for single photon detection has traditionally been provided by a photon amplification tube, such as an image intensifier, a microchannel plate photomultiplier tube (MCP PMTs), or a hybrid photodiode. Improvements to both the quantum efficiency (QE) of the photocathode and dark count rate (DCR), as well as some other factors, can improve both sensitivity and performance of any photon amplification tube, in turn improving the sensitivity of medical diagnostic imaging equipment.
Research on Temperature and Strain Rate Dependent Viscoelastic Response of Polyvinyl Butaral Film2016-01-05194/5/2016
The mechanical behavior of polyvinyl butyral (PVB) film plays an important role in windshield crashworthiness and pedestrian protection and should be depth study. In this article, the uniaxial tension tests of PVB film at various strain rates (0.001 s-1, 0.01 s-1, 0.1 s-1, 1 s-1) and temperatures (-10°C, 0°C, 10°C, 23°C, 40°C, 55°C, 70°C) are conducted to investigate its mechanical behavior. Then, temperature and strain rate dependent viscoelastic characteristics of PVB are systematically studied. The results show that PVB is a kind of temperature and strain rate sensitive thermal viscoelastic material. Temperature increase and strain rate decrease have the same influence on mechanical properties of PVB. Besides, the mechanical characteristics of PVB change non-linearly with temperature and strain rate. Finally, two thermal viscoelastic constitutive model (ZWT model and DSGZ model) are suggested to describe the tension behavior of PVB film at various strain rates and temperatures. Tension response of PVB at 0°C-70°C is simulated based on ZWT model, while tension response of PVB at -10°C is described using DSGZ model. The fitting results show good agreement with its corresponding experimental results. Results may provide basic experimental data and theoretical support to explore energy absorbing characteristics and safety design of PVB laminated glass.
Xu, Xiaoqing, Liu, Bohan, Wang, Yan, Li, Yibing
Effect of Xylene Ratio on the Secondary Atomization with UV Laser2015-32-079611/17/2015
In our study, phenomena is observed that 30µm droplet become breakup by UV laser irradiation. This phenomena change by composition of droplet. Then we focused on difference of absorbance, hexadecane and o-xylene are used as fuel. The former do not absorb UV enough and the latter do absorb UV enough. And authors examined the relation mixing ratio and breakup phenomena using blended fuel which consist of hexadecane and o-xylene. With regard to the UV laser we used, wavelength is 266nm, flash of time is 10nsec and laser intensity is 15mJ. CCD camera, strobe light with 180nsec flash time and lens of ten magnification were used for observation. As a result, we obtained the following; 1) A state of breakup phenomena depend on concentration of o-xylene. 2) The absorbance is not related with a state of breakup phenomena.
Enomoto, Hiroshi, Iwafune, Naoki, Morii, Masaya, Honda, Ryo, Hieda, Noboru, Teraoka, Yoshikazu
Hubble Spinoffs: Space Age Technology for the MassesTBMG-217083/1/2015
Over the plast 25 years, some of the sophisticated technology developed for the HST has been successfully spun off and commercialized to improve life on Earth.
Researcher Spotlight: Atom­Thick Material Offers 2D Imaging PossibilitiesTBMG-216663/1/2015
Rice University scientists have developed a two-dimensional, atom-thick, light-sensitive material called CIS, a single-layer matrix of copper, indium, and selenium atoms. Sidong Lei, a graduate student, also built a prototype — a three-pixel charge-coupled device (CCD) sensor — to prove the material’s ability to capture an image. The optoelectronic memory material may be the basis for future flat imaging devices and two-dimensional electronics.
Preparation, Planning, and Concept Demo of a Technique to Find ≈7-to-10-m Near Earth AsteroidsTBMG-203328/1/2014
A paper describes a new technique designed to increase significantly the sensitivity for finding and tracking small, dim, and fast-moving near Earth asteroids (NEAs). The technique relies on a combined use of a novel data processing approach and a new generation of high-speed CCD cameras. These new cameras have very low readout noise (≈le–) and allow taking short exposures of moving objects at high frame rates, effectively “freezing” their motion on the CCD. A long-exposure image is synthetically created as if the telescope were tracking the object with a significantly higher SNR — an approach called “synthetic tracking.” By changing the shift/add vector, multiple dim objects moving in different directions can be detected in the same data set.
CCD and CMOS SensorsTBMG-200637/1/2014
How does one select the best HD video camera and imaging sensor for professional video in applications such as life sciences, surgical imaging, microscopy, industrial imaging, and specialized point-of-view broadcasting where physical camera size is important and exceptional color video characteristics are critical?
Spatial Phase-Shift Digital Shearography for Out-of-Plane Deformation Measurement2014-01-08244/1/2014
Measuring deformation under dynamic loading is still a key problem in the automobile industry. The first spatial phase-shift shearography system for relative deformation measurement is reported. Traditional temporal phase-shift technique-based shearography systems are capable of measuring relative deformation by using a reference object. However, due to its low acquisition rate, the existing temporal phase-shift shearography system can be only used under static loading situations. This paper introduces a digital shearography system which utilizes the spatial phase-shift technique to obtain an extremely high acquisition rate. The newly developed spatial phase-shift shearography system uses a Michelson-Interferometer as the shearing device. A high power laser at 532nm wavelength is used as the light source. A one mega pixels high speed CCD camera is used to record the speckle pattern interference. The spatial frequency carrier is introduced by tilting one of the mirrors in the Michelson-Interferometer. The Fourier Transform method (FT) is used to separate the spectra on spatial frequency domain. The Windowed Inverse Fourier Transform (WIFT) method is then used to evaluate the phase information of the recorded speckle pattern interference. The newly developed spatial phase-shift shearography system is used to measure an impact on a square metal plate clamped along its entire perimeter. The theory and experiment are shown in detail in this paper.
Xie, Xin, Zheng, Yaqian, Li, Xiaona, Sia, Bernard, Zhong, Ping, Yang, Guobiao, Yang, Lianxiang
Research on Shear Test of New Style Automotive Structural Adhesive2014-01-08284/1/2014
In this paper, Digital Image Correlation Method (DICM) is employed to measure the shear mechanical property of the new style automotive structural adhesive specimens and traditional spot welded specimens under quasi static uniaxial shear tensile test. This experiment adopts a non-contact measuring method to measure the strain of specimens. A CCD and a computer image processing system are used to capture and record the real-time surface images of the specimens before and after deformation. Digital correlation software is used to process the imagines before and after deformation to obtain the specimen's strain of the moment. And then both the force-displacement curve and the stress-strain curve during the tensile process could be obtained. The test and analysis results show that the new style structural adhesive specimens have a great advantage with the spot welded specimens. It provides experimental evidence for further improvement of this structural adhesive. And the digital image correlation method is a non-contact measuring method. It has great significance in practice.
Yang, Guobiao, Chi, Yingbin, Zhu, Qirong, Yang, Lianxiang
Improving Material Property Measurement Using Multi- Camera Digital Image CorrelationTBMG-192053/1/2014
The automotive industry faces growing pressure for more efficient vehicles. This pressure comes from many sources including government regulations, decreasing natural resources, and consumer demand. As the pressure begins to rise, automakers have a growing need for better fuel, more efficient energy-generating processes, and lighter vehicles. In an effort to reduce the weight of their vehicles, automakers have shown an increasing interest in using aluminum, provided it can withstand the same deformations as steel.
Electro-Optical Boresight Weapon SystemTBMG-198292/1/2014
Senso Optics Yokneam, Israel +972-4-993-5527
Improving Signal to Noise Ratios in Defense ElectronicsTBMG-162055/1/2013
As a vertical market, “defense electronics” encompasses a huge range of systems, from portable communications to transportation, avionics, and shipborne radar. While the power architectures are as diverse as they could be, all have common operational demands — they must be robust (shock, vibration, temperature extremes), highly reliable, able to power up after periods of dormancy, and based on components with minimal obsolescence.
A Tracking Sun Photometer Without Moving PartsTBMG-1506211/1/2012
This innovation is small, lightweight, and consumes very little electricity as it measures the solar energy attenuated by gases and aerosol particles in the atmosphere. A Sun photometer is commonly used on the Earth’s surface, as well as on aircraft, to determine the solar energy attenuated by aerosol particles in the atmosphere and their distribution of sizes. This information is used to determine the spatial and temporal distribution of gases and aerosols in the atmosphere, as well as their distribution sizes.
Integrated Laser Characterization, Data Acquisition, and Command and Control Test SystemTBMG-138616/1/2012
Satellite-based laser technology has been developed for topographical measurements of the Earth and of other planets. Lasers for such missions must be highly efficient and stable over long periods in the temperature variations of orbit. In this innovation, LabVIEW is used on an Apple Macintosh to acquire and analyze images of the laser beam as it exits the laser cavity to evaluate the laser’s performance over time, and to monitor and control the environmental conditions under which the laser is tested. One computer attached to multiple cameras and instruments running LabVIEW-based software replaces a conglomeration of computers and software packages, saving hours in maintenance and data analysis, and making very longterm tests possible.
SAE Electric Vehicle and Plug in Hybrid Electric Vehicle Conductive Charge CouplerJ1772_201202 (Historical)2/21/2012
This SAE Recommended Practice covers the general physical, electrical, functional and performance requirements to facilitate conductive charging of EV/PHEV vehicles in North America. This document defines a common EV/PHEV and supply equipment vehicle conductive charging method including operational requirements and the functional and dimensional requirements for the vehicle inlet and mating connector.
Hybrid - EV Committee
Designing Optical Systems With Off-The-Shelf ProductsTBMG-126841/1/2012
Utilization of COTS (commercial off-the-shelf) products is now almost a bylaw of government and military design projects and is becoming of increasing interest in commercial designs, as well. Optical systems are no exception; the use of stock optics can provide tremendous advantages in terms of reduced cost and development effort. The key is finding the most appropriate way of employing stock optics in a custom design.
CCD Camera Lens Interface for Real-Time Theodolite AlignmentTBMG-126491/1/2012
Theodolites are a common instrument in the testing, alignment, and building of various systems ranging from a single optical component to an entire instrument. They provide a precise way to measure horizontal and vertical angles. They can be used to align multiple objects in a desired way at specific angles. They can also be used to reference a specific location or orientation of an object that has moved. Some systems may require a small margin of error in position of components. A theodolite can assist with accurately measuring and/or minimizing that error.
NASA Awards 2010 Software of the YearTBMG-110929/1/2011
The Kepler mission Science Operations Center Science Pipeline Release 6.0 software system was named 2010 NASA Software of the Year by the NASA Software Advisory Panel. Designed, developed, and operated by the Kepler Science Operations Center (SOC) at NASA’s Ames Research Center in Moffett Field, CA, the SOC software system is used to find Earth-sized planets using photometric data acquired from the
Applying HDTV Imaging Technology To Industrial ApplicationsTBMG-105487/1/2011
New high definition (HD) television cameras are being integrated into industrial environments to assist in the inspection of a variety of manufactured products. HDTV technology is reaching areas of application far outside the broadcast or entertainment markets, in part because of the capability of perfectly matching the cameras’ HD resolution, pixel to pixel, to high definition LCD and LED monitors, making these systems ideal for real-time, live viewing inspection.
Multispectral Imaging Broadens Cellular AnalysisTBMG-81357/1/2010
How does life begin and evolve? Does life exist elsewhere in the universe? What is the future of life on Earth and beyond?
SAE Electric Vehicle and Plug in Hybrid Electric Vehicle Conductive Charge CouplerJ1772_201001 (Historical)1/15/2010
This SAE Recommended Practice covers the general physical, electrical, functional and performance requirements to facilitate conductive charging of EV/PHEV vehicles in North America. This document defines a common EV/PHEV and supply equipment vehicle conductive charging method including operational requirements and the functional and dimensional requirements for the vehicle inlet and mating connector.
Hybrid - EV Committee
Machinery & Equipment Category WinnerTBMG-50634/1/2009
Direct-Solve Image-Based Wavefront SensingTBMG-50414/1/2009
A method of wavefront sensing (more precisely characterized as a method of determining the deviation of a wavefront from a nominal figure) has been invented as an improved means of assessing the performance of an optical system as affected by such imperfections as misalignments, design errors, and fabrication errors. Unlike some prior methods, this method does not require the use of an expensive, complex interferometric instrument for testing the optical system of interest: indeed, if the system under test includes an image sensor at its focal plane, then this method does not require any optical instrumentation other than the optical system under test. Unlike some other prior methods, this method does not involve processing of multiple defocused images by a nonlinear iterative phase-retrieval algorithm and interpretation of results by a human expert in phase retrieval. Instead, this method involves a single non-iterative algorithm that solves for the wavefront from a single in-focus image, without need for interpretation of results. Hence, the main advantages of this method over the prior methods are reduced computing time and reduced labor.
Cell-Detection Technique for Automated Patch ClampingTBMG-28025/1/2008
A unique and customizable machine-vision and image-data-processing technique has been developed for use in automated identification of cells that are optimal for patch clamping. [Patch clamping (in which patch electrodes are pressed against cell membranes) is an electrophysiological technique widely applied for the study of ion channels, and of membrane proteins that regulate the flow of ions across the membranes. Patch clamping is used in many biological research fields such as neurobiology, pharmacology, and molecular biology.] While there exist several hardware techniques for automated patch clamping of cells, very few of those techniques incorporate machine vision for locating cells that are ideal subjects for patch clamping. In contrast, the present technique is embodied in a machine-vision algorithm that, in practical application, enables the user to identify “good” and “bad” cells for patch clamping in an image captured by a charge-coupled-device (CCD) camera attached to a microscope, within a processing time of one second. Hence, the present technique can save time, thereby increasing efficiency and reducing cost.
Medical X-Ray Imaging System Improves Patient DiagnosisTBMG-134643/1/2008
For more than 40 years, Italray srl (Florence, Italy) has manufactured radiological equipment for traditional and digital medical applications, as well as computer-assisted systems dedicated to radiological purposes. The company’s solutions — which range from simple mobile x-ray equipment to complete radiology/ fluoroscopy diagnostic installations for traditional and digital radiology applications and angiography — are used in hospitals, universities, private research centers, and nursing homes in Europe and other parts of the world.
eROSITA Camera Low Temperature Thermal Control2008-01-19571/29/2008
eROSITA (extended ROentgen Survey with an Imaging Telescope Array) is a powerful X-ray telescope under development by the Max-Planck-Institut für extraterrestrische Physik (MPE) in Garching, Germany. eROSITA is the core instrument on the Russian SRG1 mission which is planned for launch in 2011. It comprises seven nested Wolter-I grazing incidence telescopes, each equipped with its own CCD camera. The mirror modules have to be maintained at 20°C while the cameras are operated at -80°C. Both, mirrors and CCDs have to be kept within tight limits. The CCD cooling system consists of passive thermal control components only: two radiators, variable conductance heat pipes (VCHP) and two special thermal storage units. The orbit scenario imposes severe challenges on the thermal control system and also on the attitude control system. This paper deals with the evaluation of the orbit parameters and the definition of the constraints for the thermal control system which are needed to match the temperature requirements. It presents the selected thermal control solution, its predicted performance and reports on test results obtained from an engineering model.
Fürmetz, Maria, Eder, Josef, Predehl, Peter, Tiedemann, Lars
Combining Multimode Emissions from Broad Area Laser Diodes into Single-Mode Spots without FeedbackTBMG-111521/1/2008
Broad-area laser diodes are the most efficient coherent light sources and are widely used today. The extraordinary efficiency, modulation easiness, availability to virtually any wavelength and compactness are the principle drives stimulating the development of light sources based on laser diodes. However, due to fundamental limitations of laser diode gain medium, the emission from laser diodes has a major drawback — the emission is not spatially coherent. In other words laser diode light is often seen as a light bulb emission that cannot be focused in a diffraction limited spot of λ/2 or easily transmitted as a narrow beam. Despite the fact that kilowatts of multimode power can be easily extracted from a laser diode array, the resulting single-lobe single-element power from a laser diode is always limited by a value of several watts. Many applications are waiting for a spatially coherent laser diode source offering power from 1 to 100W. The potential substitution of YAG and fiber lasers by a compact, direct single- mode laser diode source would bring significant advancements in a number of applications such as LIDAR/LADAR (Light Intensity Detection and Ranging/Light Amplification Detection and Ranging) systems; high-bit-rate, long-haul free space communication systems; industrial processing applications; and many more.
Visualization Software Helps Assess Thin-Film Semiconductor SystemsTBMG-1344712/1/2007
As thin-film technology advances, it’s increasingly important to monitor the film’s characteristics. That’s because eliminating irregularities in thin films — used primarily to create computer chips — enhances their performance. k-Space Associates (kSA, Ann Arbor, MI) specializes in accurate, precise monitoring methods that allow physicists and engineers to create high-performance thin-film products and improve their research and development workflow.
Robust Mapping of Incoherent Fiber-Optic BundlesTBMG-116769/1/2007
A method and apparatus for mapping between the positions of fibers at opposite ends of incoherent fiber-optic bundles have been invented to enable the use of such bundles to transmit images in visible or infrared light. The method is robust in the sense that it provides useful mapping even for a bundle that contains thousands of narrow, irregularly packed fibers, some of which may be defective.
High-Speed Noninvasive Eye-Tracking SystemTBMG-20898/1/2007
The figure schematically depicts a system of electronic hardware and software that noninvasively tracks the direction of a person’s gaze in real time. Like prior commercial noninvasive eye-tracking systems, this system is based on (1) illumination of an eye by a low-power infrared light-emitting diode (LED); (2) acquisition of video images of the pupil, iris, and cornea in the reflected infrared light; (3) digitization of the images; and (4) processing the digital image data to determine the direction of gaze from the centroids of the pupil and cornea in the images. Relative to the prior commercial systems, the present system operates at much higher speed and thereby offers enhanced capability for applications that involve human-computer interactions, including typing and computer command and control by handicapped individuals, and eye-based diagnosis of physiological disorders that affect gaze responses.
A New Calibration Method for Digital 3D Profilometry System2007-01-13804/16/2007
Recently the use of digital 3D profilometry in the automotive industries has become increasingly popular. The effective techniques for 3D shape measurement, especially for the measurement of complicated structures, have become more and more significant. Different optical inspective methods, such as 3D profilometry, laser scanning and Coordinate-Measuring Machine (CMM), have been applied for 3D shape measurement. Among these methods, 3D profilometry seems to be the fastest and inexpensive method with considerably accurate result, and it has simple setup and full field measuring ability compared with other techniques. In this paper, a novel calibration method for 3D-profilometry will be introduced. In this method, a multiple-step calibration procedure is utilized and best-fit calibration curves are obtained to improve measurement accuracy. A recursive algorithm is used for data evaluation, along with calibration data. Sources of measuring errors are discussed and solutions are suggested. The calibration method can effectively improve the measurement accuracy for 3D profilometry system, especially, for measurement of samples with big depth change. Applications of this technique in automotive industry for 3D shape measurement will be presented and limitations will be discussed.
Liu, Sheng, Samala, Praveen R., Zhu, Zhaojing, Yang, Lianxiang
CCDs Find Applications in Diverse Space MissionsCCDs Find Applications in Diverse Space MissionsTBMG-5628/1/2006
Charge coupled device (CCD) image sensors e2v Technologies Elmsford, NY 914-593-6841
Improved Photon-Emission-Microscope SystemTBMG-15035/1/2006
An improved photon-emission-microscope (PEM) instrumentation system has been developed for use in diagnosing failure conditions in semiconductor devices, including complex integrated circuits. This system is designed primarily to image areas that emit photons, at wavelengths from 400 to 1,100 nm, associated with device failures caused by leakage of electric current through SiO2 and other dielectric materials used in multilayer semiconductor structures. In addition, the system is sensitive enough to image areas that emit photons during normal operation. This system supplants a prior PEM system based on a photon-intensified, gated, charge-coupled-device (CCD) camera.
Improved Photon-Emission-Microscope SystemTBMG-120815/1/2006
An improved photon-emission-microscope (PEM) instrumentation system has been developed for use in diagnosing failure conditions in semiconductor devices, including complex integrated circuits. This system is designed primarily to image areas that emit photons, at wavelengths from 400 to 1,100 nm, associated with device failures caused by leakage of electric current through SiO2 and other dielectric materials used in multilayer semiconductor structures. In addition, the system is sensitive enough to image areas that emit photons during normal operation. This system supplants a prior PEM system based on a photon-intensified, gated, charge-coupled-device (CCD) camera.
Perception and Autonomous Navigation Using a Priori Data2006-01-11604/3/2006
Autonomous Navigation for military unmanned ground vehicles requires the ability to act without human intervention in increasingly difficult environments such as off-road terrain and military operations in urban terrain (MOUT). One method to accomplish this is through the combination of a local perception sensor suite with an a priori route planner and a local guidance algorithm that provides an automated obstacle detection, classification, and avoidance capability. This paper will detail the feasibility of this approach based on preliminary test results.
Conrad, Kevin L., Galloway, John R., Irwin, William P., Delashmit, Walter H., Jack, James T., Kuntimad, Govindaraj, Muguira, Maritza R., Little, Charles Q., Peters, Ralph R.
Computer Vision for Shape and Deformation Measurements: Recent Developments and Applications2006-01-05264/3/2006
Applications using two-dimensional and three-dimensional computer vision for deformation and shape measurements are described. First, the use of 2D image correlation for estimation of properties in heterogeneous materials is demonstrated. Second, the use of 3D computer vision for shape and deformation measurements in large, flawed panels is presented. Finally, the use of 3D computer vision for deformation measurement in cracked, ductile materials undergoing complex loading conditions is shown.
Sutton, Michael A., Yan, Junhui
Accurate Measurement of PVT Data for PP/Gas and TPO/Gas Mixtures2006-01-05064/3/2006
Foaming of a thermoplastic polyolefin (TPO) is gaining interests because of its superior mechanical properties of foamed automotive parts, such as lightweight and high performance to weight ratio, etc. In this context, understanding of the thermophysical properties of PP/gas and TPO/gas mixtures is critically important. This paper will present the newly developed experimental technique to accurately measure the swelling of PP and TPO due to gas dissolution at elevated temperatures and pressures. Our technique measures the geometry of the pendent drop accurately from the captured images to obtain the volume swelling data. It determines the boundary location of the polymer/gas sample accurately by magnifying the sample drop locally along its edge before capturing the image. The automated high-precision XY stage is chosen as the platform to control the motion of the CCD camera. Those images are reconstructed into one big image in the virtual domain based on the original pixel coordinates from individual images. By applying the curve fitting and integration technique, we finally determine the volume swelling of the PP/gas and TPO/gas mixtures.
Li, Y. G., Li, H. B., Park, C. B.
Two-Reference Beam Double-Pulsed Holographic Interferometry with Direct Phase Measurement in Transient Processes Study2006-01-07694/3/2006
Holographic interferometry has been successfully employed to characterize both static and dynamic behavior of diverse types of structure under stress. Double-exposure pulsed holographic interferometry has been extensively used in performing the vibration analysis and qualitative investigations of deformation of the non-stationary objects. One of the most important advantages of this technique is that it can be used for quantitative measurements of the transient processes (e.g. shock wave propagation). However, in conventional double-pulsed interferometry it is sometimes difficult to get phase information from a single set of holograms. Applying two-reference beam recording set-up to double-exposure pulsed holographic interferometry makes it possible to obtain phase-shifted interferograms from a single interferogram of the tested object and retrieve the phase information for OPD (optical path difference) map creation. Two-reference beam double-pulsed Ruby laser holographic interferometer has been adapted to transient and continuous phenomena studies. It is non-destructive, real-time, and definitive approach in identification of vibrational modes, displacements, and motion geometries. Results of a vibration study performed by double-pulsed Ruby laser holographic interferometry for wave excited by shaker with continuous sinusoidal excitation and propagated over the car door panel surface are presented in this paper.
Grabovskyy, Vitaliy, Yashnyk, Viktor
Progress in Insect-Inspired Optical Navigation SensorsTBMG-60110/1/2005
Progress has been made in continuing efforts to develop optical flight-control and navigation sensors for miniature robotic aircraft. The designs of these sensors are inspired by the designs and functions of the vision systems and brains of insects. Two types of sensors of particular interest are polarization compasses and ocellar horizon sensors. The basic principle of polarization compasses was described (but without using the term “polarization compass”) in “Insect-Inspired Flight Control for Small Flying Robots” (NPO-30545), NASA Tech Briefs, Vol. 29, No. 1 (January 2005), page 61. To recapitulate: Bees use sky polarization patterns in ultraviolet (UV) light, caused by Rayleigh scattering of sunlight by atmospheric gas molecules, as direction references relative to the apparent position of the Sun. A robotic direction-finding technique based on this concept would be more robust in comparison with a technique based on the direction to the visible Sun because the UV polarization pattern is distributed across the entire sky and, hence, is redundant and can be extrapolated from a small region of clear sky in an elsewhere cloudy sky that hides the Sun.
Stellar Gyroscope for Determining Attitude of a SpacecraftTBMG-51810/1/2005
A paper introduces the concept of a stellar gyroscope, currently at an early stage of development, for determining the attitude or spin axis, and spin rate of a spacecraft. Like star trackers, which are commercially available, a stellar gyroscope would capture and process images of stars to determine the orientation of a spacecraft in celestial coordinates. Star trackers utilize charge coupled devices as image detectors and are capable of tracking attitudes at spin rates of no more than a few degrees per second and update rates typically <5 Hz. In contrast, a stellar gyroscope would utilize an active pixel sensor as an image detector and would be capable of tracking attitude at a slew rate as high as 50°/s, with an update rate as high as 200 Hz. Moreover, a stellar gyroscope would be capable of measuring a slew rate up to 420°/s. Whereas a Sun sensor and a three-axis mechanical gyroscope are typically needed to complement a star tracker, a stellar gyroscope would function without them; consequently, the mass, power consumption, and mechanical complexity of an attitude-determination system could be reduced considerably.
Multipurpose Hyperspectral Imaging SystemTBMG-291648/1/2005
A hyperspectral imaging system of high spectral and spatial resolution that incorporates several innovative features has been developed to incorporate a focal-plane scanner (U.S. Patent 6,166,373). This feature enables the system to be used for both airborne/spaceborne and laboratory hyperspectral imaging with or without relative movement of the imaging system, and it can be used to scan a target of any size as long as the target can be imaged at the focal plane; for example, automated inspection of food items and identification of single-celled organisms. The spectral resolution of this system is greater than that of prior terrestrial multispectral imaging systems. Moreover, unlike prior high-spectral-resolution airborne and spaceborne hyperspectral imaging systems, this system does not rely on relative movement of the target and the imaging system to sweep an imaging line across a scene.
Surface Flatness Measurement Through a Digital 3D Profilometry System2005-01-08934/11/2005
Digital 3D profilometry is a non-contact, full-field, and fast method for 3D profile digitization. It has a relatively simple setup and acceptable measurement accuracy. Surface flatness plays an important role in many circumstances, such as sealing and contact. Using digital 3D profilometry to measure surface flatness is a new challenge to researchers. In this paper, new development is presented on how to measure surface flatness. Principles and procedures are described in detail. Measurement applications are given and limitations are discussed.
Liu, Sheng, Samala, Praveen R., Yang, LianXiang
Integrated Pointing and Signal Detector for Optical ReceiverTBMG-7273/1/2005
A design concept for the receiver portion of a proposed free-space optical communication terminal calls for integration of its communication and pointing detectors. As explained below, this would entail a departure from prior designs, in which pointing and communication detectors have been separate.
Compact Instrument for Measuring Profile of a Light BeamTBMG-2930811/1/2004
The beamviewer is an optical device designed to be attached to a charge-coupled-device (CCD) image detector for measuring the spatial distribution of intensity of a beam of light (the "beam profile ") at a designated plane intersecting the beam. The beamviewer-and-CCD combination is particularly well suited for measuring the radiant-power profile (for a steady beam) or the radiant-energy profile (for a pulsed beam) impinging on the input face or emerging from the output face of a bundle of optical fibers. The beamviewer-and-CCD combination could also be used as a general laboratory instrument for profiling light beams, including beams emerging through small holes and laser beams in free space.
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