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Advanced Coupled-cavity Etalon (ACE) significantly improves both in-band transmission and out-of-band rejection. In some cases, 12% more light is transmitted inside the passband and >3x more light is rejected outside the passband. Incorporating ACE into the recirculating etalon receiver (RER) improves performance significantly. ACE increases the wavelength resolution and enables closer channel spacing resulting in a very efficient, high resolution spectrometer. RACER has both high resolution and a high photon efficiency which allows flexibility for trading different combinations of reduced cross-talk and closer channel spacing.

The Wavefront Aberrations (WA) are a collection of different sorts of optical defects, including the familiar defocus and astigmatism that are corrected by eyeglasses, but also more complex higher order aberrations such as coma, spherical aberration, and others. The WA provide a comprehensive description of the optics of the eye, and thus determine the acuity. But until recently, a practical method of computing this relationship did not exist. Our solution to this problem is to simulate the observer performing the acuity task with an eye possessing a particular set of WA. When a letter is presented, we first distort a digital image of the letter by the specified WA, and add noise to mimic the noisiness of the visual system. From previous research, we have determined the appropriate noise level to match human performance. We then attempt to match the blurred noisy image to similarly blurred candidate letter images, and select the closest match. We repeat this for many trials at many letter sizes, and thereby determine the smallest letter than can be reliably identified: the visual acuity. We have streamlined and simplified the key steps for this simulation approach so that the entire process is robust, accurate, simple and fast. Results are typically obtained in a few seconds.

Originally conceived as a method to generate pressurized pure oxygen for extravehicular activity (EVA) suits worn on the International Space Station, Glenn's technology represents a significant breakthrough. The generator is an all-solid-state device that separates oxygen from air, water, or carbon dioxide and electrochemically pumps it to a high pressure in a multi-stage process. Glenn's design features a solid oxide electrolysis (SOE) stack, based on bi-supported cell design, that is structurally supported by two electrode layers. Sandwiched between the cathode and anode sides is an oxygen-ion conducting solid-state electrolyte membrane, made of yttria-stabilized zirconia (YSZ). These membranes form the individual SOE cells within the stack, and each cell carries out a single stage of the multi-stage process, with each stage incrementally pressurizing the oxygen. A voltage (1.5 to 2 volts) is applied across the cell, and the air or other input is supplied to the cathode side, where the oxygen dissociates into oxygen ions. The YSZ membrane will conduct only the oxygen ions, producing pure, dry oxygen. The entire stack is wrapped in a glass ceramic seal, providing a pressure vessel for the device. Glenn's novel stack design allows hermetic sealing and does not require a compression sealing mechanism or other spring-loaded hardware. Each cell is wired in parallel so the voltage can be controlled across each cell to avoid electrochemical reduction of the electrolyte. In addition, each cell is electrically insulated from other cells in the stack using a non-electronically conducting, ceramic-woven cloth YSZ layer. Because Glenn's process resists fouling from water containing impurities or other debris, it does not require a high-purity water source, as do other water electrolysis technologies. The oxygen product is also sterile for medical applications because of the high temperature (in excess of 600°C) at which the process operates.

NASAs Goddard Space Flight Centers method for the extraction of Lunar data and/or planetary features is a method developed to extract Lunar features based on the combination of several image processing techniques. The technology was developed to register images from multiple sensors and extract features from images in low-contrast and uneven illumination conditions. The image processing and registration techniques can include, but is not limited to, a watershed segmentation, marked point processes, graph cut algorithms, wavelet transforms, multiple birth and death algorithms and/or the generalized Hough Transform.

The in situ inspection technology for additive manufacturing combines different types of cameras strategically placed around the part to monitor its properties during construction. The IR cameras collect accurate temperature data to validate thermal math models, while the visual cameras obtain highly detailed data at the exact location of the laser to build accurate, as-built geometric models. Furthermore, certain adopted techniques (e.g., single to grouped pixels comparison to avoid bad/biased pixels) reduce false positive readings. NASA has developed and tested prototypes in both laser-sintered plastic and metal processes. The technology detected errors due to stray powder sparking and material layer lifts. Furthermore, the technology has the potential to detect anomalies in the property profile that are caused by errors due to stress, power density issues, incomplete melting, voids, incomplete fill, and layer lift-up. Three-dimensional models of the printed parts were reconstructed using only the collected data, which demonstrates the success and potential of the technology to provide a deeper understanding of the laser-metal interactions. By monitoring the print, layer by layer, in real-time, users can pause the process and make corrections to the build as needed, reducing material, energy, and time wasted in nonconforming parts.

Currently, HSEG software is being used by Bartron Medical Imaging as a diagnostic tool to enhance medical imagery. Bartron Medical Imaging licensed the HSEG Technology from NASA Goddard adding color enhancement and developing MED-SEG, an FDA approved tool to help specialists interpret medical images. HSEG is available for licensing outside of the medical field (specifically for soft-tissue analysis).

The Spatial Standard Observer (SSO) provides a tool that allows measurement of the visibility of an element, or visual discriminability of two elements. The device may be used whenever it is necessary to measure or specify visibility or visual intensity. The SSO is based on a model of human vision, and has been calibrated by an extensive set of human test data. The SSO operates on a digital image or a pair of digital images. It computes a numerical measure of the perceptual strength of the single image, or of the visible difference between the two images. The visibility measurements are provided in units of Just Noticeable Differences (JND), a standard measure of perceptual intensity. A target that is just visible has a measure of 1 JND. The SSO will be useful in a wide variety of applications, most notably in the inspection of displays during the manufacturing process. It is also useful in for evaluating vision from unpiloted aerial vehicles (UAV) predicting visibility of UAVs from other aircraft, from the control tower of aircraft on runways, measuring visibility of damage to aircraft and to the shuttle orbiter, evaluation of legibility of text, icons or symbols in a graphical user interface, specification of camera and display resolution, inspection of displays during the manufacturing process, estimation of the quality of compressed digital video, and predicting outcomes of corrective laser eye surgery.

Features of the handheld torch's design include manual controls to modify the laser diameter and power output in real time. This ability allows the user to adjust the laser depending on circumstantial needs, resulting in a torch that is well suited for in-field repairs of metals where space and time are constrained. The primary applications are likely to be in-field welding and brazing of damaged specialized equipment. The laser technology is a variable-power, continuous-wave, handheld fiber laser torch for brazing metals with an increased precision and maneuverability. The laser hardware and supply measures 24 inches in length, 15 inches in width, and 30 inches in height, with a torch diameter of about 0.8 inches. This size is nearly half that of traditional welding systems, which increases the portability of the machine as well as the welder's maneuverability. The current handheld torch replaces earlier versions of handheld torches that cost over $700K to produce and had much larger footprints. After numerous design improvements and the inclusion of a commercial off-the-shelf fiber laser, the third-generation NASA torch is much smaller, with the handheld component being about 2.5 times larger than standard ink pens. The NASA handheld torch and system integration is estimated to cost between $60K and $70K. NASA has used the handheld laser on Haynes 230 super alloy to improve localized repair procedures. Preliminary tests produced a consistent data set of yield strength (YS), ultimate tensile strength (UTS), and percent elongation (%EL) that are comparable to the results of current GTAW techniques.

The advantage of using cardiac biometrics over existing methods is that heart signatures are more difficult to forge compared to other biometric devices. Iris scanners can be fooled by contact lenses and sunglasses, and a segment of the population does not have readable fingerprints due to age or working conditions. Previous electrocardiographic signals employed a single template and compared that template with new test templates by means of cross-correlation or linear-discriminant analysis.The benefit of this technology over competing cardiac biometric methods is that it is more reliable with a significant reduction in error rates. The benefit of this technology is that it creates a probabilistic model of the electrocardiographic features of a person instead of a single signal template of the average heartbeat. The probabilistic model described as Gaussian mixture model allows various modes of the feature distribution, in contrast to a template model that only characterizes a mean waveform. Another advantage is that the model uses both physiological and anatomical characterization of the heart, unlike other methods that mainly use only physiological characterization of the heart. By combining features from different leads, the heart of the person is better characterized in terms of anatomical orientation because each lead represents a different projection of the electrical vector of the heart. Thus, employing multiple electrocardiographic leads provides a better performance in subject verification or identification.

A time-varying electrical field E, having a root-mean-square intensity of 2rms, with a non-zero gradient in a direction transverse to the liquid or fluid flow direction, is produced by a nanostructure electrode array with a very high magnitude gradient near exposed electrode tips. A dielectrophoretic force causes the selected particles to accumulate near the electrode tips, if the medium and selected particles have substantially different dielectric constants. An insulating material surrounds most of the nanostructure electrodes, and a region of the insulating material surface is functionalized to promote attachment of the selected particle species to the surface. An electrical property value Z(meas) is measured at the functionalized surface, and is compared with a reference value Z(ref) to determine if the selected species particles are attached to the functionalized surface. An advantage of this innovation is that an array of nanostructure electrodes can provide an electric field intensity gradient that is one or more orders of magnitude greater than the corresponding gradient provided by a conventional microelectrode arrangement. As a result of the high magnitude field intensity gradients, a nanostructure concentrator can trap particles from high-speed microfluidic flows. This is critical for applications where the entire analysis must be performed in a few minutes.