Strobing to Mitigate Vibration for Display Legibility

Blur is eliminated with appropriate strobing frequency. Ames Research Center, Moffett Field, California This method mitigates the motion blur introduced when a display, and/or the operator reading it, is undergoing vibration (e.g. during the launch phase of spaceflight). If both the operator and the display are undergoing vibration, their respective impulses need not be in phase. This mitigation occurs when the display is illuminated at a strobing rate that corresponds with the frequency of the vibration. This can be done either by strobing the ambient illumination in the environment (e.g., if the operator is reading a reflective surface display), or by strobing the display itself (e.g., strobing the LED backlighting of an electronic display).

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Imaging Space System Architectures Using a Granular Medium as a Primary Concentrator

Higher-resolution optics provide improved hyperspectral imaging for ocean and land monitoring, as well as exoplanet detection. NASA’s Jet Propulsion Laboratory, Pasadena, California Typically, the cost of a space observatory is driven by the size and mass of the primary aperture. Generally, a monolithic aperture is much heavier and complex to fabricate (hence, more costly) than an aperture of the same size but composed of much smaller units. Formation flying technology, as applied to swarm systems in space, is an emerging discipline.

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Image Processing Method To Determine Dust Optical Density

John F. Kennedy Space Center, Florida Image processing techniques for determining dust optical density in Apollo videos have been developed. The software generates histograms, and calculates the mean and standard deviation, which are then used to match dusty and clear images for the purpose of estimating an effective optical density. A dust thickness model, based on the tilt of the camera and increasing thickness of the dust layer towards the top of the image, is used to account for the distance light travels through dust.

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Vibration and Thermal Cycling Apparatus for Cryogenic Tanks

Key design characteristics can be reliably and repeatedly tested together or separately as required by the design requirements. John F. Kennedy Space Center, Florida Understanding thermal and mechanical behaviors and their inter-dependencies of complex tank systems is crucial to making proper design decisions. Low-maintenance, high-performance systems are becoming more important as global energy demands and efficiency requirements increase.

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Integrated Rate Isolation Sensor

Sensor allows for fault detection and isolation using only two IMUs. Lyndon B. Johnson Space Center, Houston, Texas Some vehicles use an internal measurement unit (IMU) system to determine the speed, acceleration, orientation, position, and/or direction of movement of the vehicle. Vehicles used for high-availability or life-critical systems may employ a fault-tolerant IMU design. Typically, such vehicles use three or more IMUs to detect the failure of an IMU and isolate the failing IMU from the other functional IMUs. A fault-tolerant system having multiple IMUs pays an associated mass, power, and volume penalty for each additional IMU. The mass/power/volume (M/P/V) of a fault-tolerant IMU system is the M/P/V of an individual IMU multiplied by the number of IMUs employed to do fault tolerance. Furthermore, each additional IMU adds to the cost of a fault-tolerant system.

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Mercury-Cadmium-Telluride Focal Plane Array for Warm Alignment of Imaging Spectroscopy Systems

This array minimizes the need to cold-cycle instrumentation, reducing cost and time for integration and testing. NASA’s Jet Propulsion Laboratory, Pasadena, California A new technique allows a mercury-cadmium-telluride (MCT) focal plane array (FPA) to operate at room temperature. These results were obtained through experimentation by varying the integration time, frame rate, and bias levels to optimize the output when warm.

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Enhanced Auditory Alert Systems

Spatial modulation is used to improve the detectability of an alert signal. Ames Research Center, Moffett Field, California Auditory warning systems for human interfaces are often designed around criteria that depend primarily upon signal loudness. It is well understood from the auditory literature that, by making an alert signal substantially louder than the measured background noise level, one can insure that an alert signal will be detectable. Such auditory alert systems have been used in the aviation industry for a number of years in order to raise the awareness of the crew for terrain proximity, for example. However, if an alert signal amplitude is too loud, the alert signal may produce a “startle effect” that hinders performance in some high-stress situations.

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