Home

CT-CURS: Unwrapping/Re-slicing Software for Cylindrical Objects Inspected Using Computed Tomography

This method provides 10¥ greater ability to resolve flaws in cylindrical CT data. John H. Glenn Research Center, Cleveland, Ohio Ultra-thin-wall metallic cylinders are extremely difficult to analyze for flaws from top-view X-ray computed tomography (CT) slices and volume renderings. A protocol has been developed using software to unwrap and re-slice the ultra-thinwall cylinder CT data into 2D sheets from the exterior to the interior of the cylinder. This method is based on interior and exterior surface edge detection, and under proper conditions, is fully automated and requires no input from the user except proper voxel dimension from the CT experiment and wall thickness of the part. By performing this transformation to a series of 2D sheets, and utilizing a local contrast expansion method in which each sheet is automatically contrast expanded between its minimum and maximum gray values, the flaws “pop out” at the inspector. This software has allowed NASA to extend the in-house world-class micro-computed tomography method for 10x better flaw resolution for cylindrical structures.

Posted in: Briefs, Electronics & Computers

Read More >>

Trajectory Specification for High-Capacity Air Traffic Control

Automating separation monitoring and guidance would relieve human controllers of the primary responsibility for safe separation. The doubling or tripling of airspace capacity that will be needed over the next several decades will require that tactical separation guidance be automated for appropriately equipped aircraft in high-density airspace. Four-dimensional (4D) trajectory assignment (three-dimensional position as a function of time) will facilitate such automation. A standard trajectory specification format based on XML (Extensible Markup Language) is proposed for that purpose.

Posted in: Briefs, TSP, Electronics & Computers

Read More >>

Co-Optimized, Blunt-Body Re-entry Vehicle Design Process

A document describes a design optimization method for determining optimal shapes for vehicles with mid-range lift-to-drag ratios that are entering or re-entering planetary atmospheres. The design space includes consideration of hypersonic aerothermodynamic properties (for minimizing heating) and hypersonic aerodynamic properties (for maximizing maneuverability and stability). It allows for flexible trajectory design. The method allows geometry and analysis grids (meshes) to be rapidly created from a limited set of parameters, which once defined, can be interpreted in a straightforward and intuitive manner.

Posted in: Briefs, TSP, Electronics & Computers

Read More >>

Adaptive Periodic-Correlation Algorithm for Shack-Hartmann Wavefront Sensing

Conventional Shack-Hartmann Wavefront Sensing requires a point source such as a star to perform wavefront sensing. This software allows one to conduct such sensing using an extended-scene or scene-based image. The software allows a Shack-Hartmann Wavefront Sensor (SH-WFS) to be used with an extended scene. It estimates the shift between the positions of a reference and test extended-scene sub-images or cells.

Posted in: Sensors, Briefs, TSP, Electronics & Computers

Read More >>

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: Briefs, TSP, Electronics & Computers

Read More >>

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: Briefs, TSP, Electronics & Computers

Read More >>

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: Briefs, TSP, Electronics & Computers

Read More >>