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Atmospheric Turbulence Modeling for Aero Vehicles

An accurate way was developed to model atmospheric turbulence that will help improve new vehicle design. Atmospheric turbulences are fractional order, and because of that, it is difficult to simulate these disturbances. Past models fall short in providing sufficiently accurate simulation of atmospheric turbulence, especially at high altitudes, for control designs of high-speed atmospheric vehicles. In this innovation, fractional order approximations representative of actual atmospheric turbulence have been formulated that fit measured atmospheric turbulence. This is accomplished by scaling the Kolmogorov spectral factorizations to convert them into finite energy von Karman forms, and then by deriving an explicit fractional circuit-filter analog for this model.

Posted in: Information Sciences, Electronics & Computers, Briefs, TSP

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Autonomic Quiescence

An alternative method to self-destruct shuts down an agent or craft that is in danger or endangering a mission. Goddard Space Flight Center, Greenbelt, Maryland Biologically inspired autonomous and autonomic systems (AAS) are essentially about creating self-directed and self-managing systems based on metaphors such as that of the autonomic nervous system. Agent technologies have been identified as a key enabler for engineering autonomy and autonomicity in systems, both in terms of retrofitting into legacy systems and designing new systems. Handing over responsibility to the systems raises concerns for humans. This invention is a result of continued investigation into a strand of research on how to engineer self-protection mechanisms into the systems to assist in providing mechanisms to control the scope and consequences of using autonomy and autonomicity.

Posted in: Electronics & Computers, Briefs, TSP

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A Decision Support Tool to Assess Upper-Level Winds for Space Launch

Faster, more reliable forecasts have been developed. An Excel-based graphical user interface (GUI) was developed for the 45th Weather Squadron (45 WS) Launch Weather Officers (LWOs), allowing them to assess numerical weather prediction model forecasts of upper-level winds and compare the forecasts to observations from Cape Canaveral Air Force Station meteorological soundings and the Kennedy Space Center 50-MHz Doppler Radar Wind Profiler in support of space launch operations at the Eastern Range. The GUI allows the LWOs to first initialize the models by comparing the 0-hour model forecasts to the observations, and then to display model forecasts in 3-hour intervals from the current time through 12 hours.

Posted in: Information Sciences, Electronics & Computers, Briefs, TSP

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GPU Lossless Hyperspectral Data Compression System

Hyperspectral imaging systems onboard aircraft or spacecraft can acquire large amounts of data, putting a strain on limited downlink and storage resources. Onboard data compression can mitigate this problem but may require a system capable of a high throughput. In order to achieve a high throughput with a software compressor, a graphics processing unit (GPU) implementation of a compressor was developed targeting the current state-of-the-art GPUs from NVIDIA®.

Posted in: Electronics & Computers, Briefs

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Calculation of Operations Efficiency Factors for Mars Surface Missions

Several modeling methods are examined. For planning of Mars surface missions, to be operated on a sol-by-sol basis by a team on Earth (where a “sol” is a Martian day), activities are described in terms of “sol types” that are strung together to build a surface mission scenario. Some sol types require ground decisions based on a previous sol’s results to feed into the activity planning (“ground in the loop”), while others do not. Due to the differences in duration between Earth days and Mars sols, for a given Mars local solar time, the corresponding Earth time “walks” relative to the corresponding times on the prior sol/day. In particular, even if a communication window has a fixed Mars local solar time, the Earth time for that window will be approximately 40 minutes later each succeeding day. Further complexity is added for non-Mars synchronous communication relay assets, and when there are multiple control centers in different Earth time zones.

Posted in: Information Sciences, Electronics & Computers, Briefs, TSP

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Fuzzy Neuron: Method and Hardware Realization

Simple and effective learning functions and adaptive elements can be placed into small hardware systems to include instruments for space, bioimplantable devices, and stochastic observers.

Posted in: Electronics & Computers, Briefs, TSP

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Frequency-Modulated, Continuous-Wave Laser Ranging Using Photon-Counting Detectors

Optical ranging is a problem of estimating the round-trip flight time of a phase- or amplitude-modulated optical beam that reflects off of a target. Frequency-modulated, continuous-wave (FMCW) ranging systems obtain this estimate by performing an interferometric measurement between a local frequency- modulated laser beam and a delayed copy returning from the target. The range estimate is formed by mixing the target-return field with the local reference field on a beamsplitter and detecting the resultant beat modulation. In conventional FMCW ranging, the source modulation is linear in instantaneous frequency, the reference-arm field has many more photons than the target-return field, and the time-of-flight estimate is generated by balanced difference- detection of the beamsplitter output, followed by a frequency-domain peak search.

Posted in: Electronics & Computers, Briefs

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