Airborne Wind Profiling Algorithm for Doppler Wind Lidar

This novel method enables accurate, real-time parameter estimation in noisy environments.NASA’s Langley Research Center has developed an algorithm, Airborne Wind Profiling Algorithm for Doppler Wind Lidar (APOLO), that offers highly accurate, real-time measurement of wind parameters (i.e., direction and speed) by airborne wind lidar sensors. APOLO enables the extraction of accurate wind speed and direction from noisy flight environments, and provides correction for instrument installation biases. The algorithm has been incorporated into a supporting software package that displays accurate airborne Doppler wind lidar data, and offers several data post-processing and display functionalities. The offset compensation and parameter extraction technology could be used in a variety of applications where the motion and orientation of a lidar sensor may result in data inaccuracy. NASA is seeking licensees that may benefit from integration of the compensation algorithm and data post-processing software into existing or developing systems.

Posted in: Briefs, Software, Mathematical models, Lidar, Data management, Test equipment and instrumentation, Aerodynamics


NETMARK Fast Search

Applications include enterprise knowledge management, and document and content management systems.The problem that motivated this work was one of analyzing hundreds of thousands of records of historical problem failure reports (aka, problem reports and corrective actions — PRACA) for improved mission safety. Whenever there is an anomaly in mission design or operations, the anomaly gets entered into a problem failure reporting database for tracking purposes. The objective of the research was to make this data queryable and analyzable using the NETMARK XML database.

Posted in: Briefs, Software, Failure analysis, Computer software and hardware, Data management, Research and development, Technical review


Adaptive Refinement Tools for Tetrahedral Unstructured Grids

This software can potentially be used in aerospace, aviation, and automotive applications. NASA’s Langley Research Center engineers have developed a new software package for more facile computational fluid dynamics. The software’s fast user run time, robustness, and efficiency have enabled its extensive use in space shuttle modeling. Adaptive Refinement Tool (ART) permits the computational modeling of flow, including jet or rocket plumes, wakes, and shocks via unstructured tetrahedral grids. Commercially available software packages often struggle to sufficiently and quickly model such complex examples of flow. ART also allows cells to be divided into two, four, or eight cells as compared to traditional software, which allows cell division only in units of eight. This is advantageous as it allows the user to control cell division more succinctly. ART executes commands via colloquial English, and has built-in internal statistical programming that increases its ease of use. ART allows the user the choice of alternate variables such as temperature or pressure at will, which facilitates modeling unusual or unlikely occurrences.

Posted in: Briefs, Software, Computational fluid dynamics, Computer software and hardware


Self-Stabilizing, Byzantine-Fault-Tolerant Clock Synchronization System and Method

Initially developed for wired applications, the technology could also be applied to wireless systems. NASA’s Langley Research Center has developed a portfolio of technologies regarding clock synchronization in distributed systems. Distributed synchronous systems that need to provide globally coordinated operations require each component (node) in the system to be precisely synchronized. Such systems could include electronic components within an aircraft or automobile, or large-scale networks of components that communicate with each other (e.g. multiple aircraft or automobiles). NASA’s technologies provide for very quick synchronization while tolerating various faults. These protocols provide distributed autonomous synchronization (i.e. no master clock signal required) and do not rely on any assumptions regarding the initial state of the system or internal status of the nodes.

Posted in: Briefs, Software, Calibration, Communication protocols, Electronic control systems


Method of Performing Computational Aeroelastic Analyses

This technology can be used for dynamic behavioral models of large buildings, bridges, dams, and towers. NASA’s Langley Research Center has developed unsteady aerodynamic Reduced-Order Models (ROMs) that significantly improve computational efficiency compared to traditional analyses of aeroelastic and other complex and unsteady systems. Traditional methods rely on the repetitive use of aeroelastic computational fluid dynamics (CFD) codes, and the iteration between the structural and nonlinear aerodynamic models of the aeroelastic CFD code for predicting the aeroelastic response of flight vehicles is very time-consuming and computationally expensive. The new ROMs are quite different from the traditional aeroelastic analysis tools, and enable the computational aeroelastic analysis of flight vehicles at a fraction of the time and cost.

Posted in: Briefs, Software, Mathematical models, Aerodynamics


Fourier Transform Spectrometer Performance Modeling

This software models the performance of a Fourier transform spectrometer (FTS). More specifically, it is able to add a number of noise/error sources to the interferogram and transform the errors back to the spectral domain.

Posted in: Briefs, Software, Finite element analysis, Computer software and hardware, Spectroscopy, Noise


Mesh Adaptation Module for Cartesian Meshes with Embedded Boundaries

Future applications include rapid prototyping, computer-based imaging and visualization, and semiconductor device modeling. This work extends the mesh generation capability of NASA’s Cart3D flow simulation software package to permit cell-by-cell mesh enrichment. Cart3D allows users to perform automated Computational Fluid Dynamics (CFD) analysis on a complex geometry. It includes utilities for geometry import, surface modeling and intersection, mesh generation, flow simulation, and post-processing of results. Geometry enters into Cart3D in the form of surface triangulations that may be generated from within Computer-Aided Design (CAD) packages, from legacy surface triangulations, or from structured surface grids. Cart3D uses adaptively refined Cartesian grids to discretize the space surrounding geometry, and cuts the geometry out of the set of cut-cells that actually intersects the surface triangulation.

Posted in: Briefs, Software, CAD, CAM, and CAE, Computational fluid dynamics


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