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<p>Processing and plotting large amounts of data can be time consuming and expensive, particularly for data that specify time-varying values, so-called time history data. DthData--along with QuickPlot and DthDiff--helps manage several key operations for time history data, enable comparison of the time history files, and efficiently plot gigabytes to terabytes of data.</p> <p>A standalone command-line-driven utility program written in ANSI-C, DthData is designed to extract selected signals and time segments from input files and write the selected data to output files. Other capabilities include converting file formats, merging data from multiple input files, time skewing, interpolating to common output frame times, renaming signals, and generating calculated output signals as functions of the input signals. The utility also converts time history files from a compressed format to any format suitable for displaying or plotting, including MATLAB&reg; or Microsoft Excel&reg; formats. (MATLAB is a registered trademark of The MathWorks, Inc. Microsoft and Excel are registered trademarks of Microsoft Corporation in the United States and/or other countries.)</p> <p>BENEFITS</p> <p>The QuickPlot-DthDiff-DthData suite of software tools offers several benefits:</p> <p> * Powerful: Processes large amounts of data from multiple sources and allows users to convert data files from one format to another</p> <p> * Efficient: Time-tags data files, enabling time-range processing of a selected parameter or set of parameters</p> <p> * Fast: Reads and plots data in a fraction of the time required for conventional data-plotting utilities</p> <p> * Simple: Offers a graphical user interface for command input and data plotting</p> <p> * Economical: Works without back-end processing systems, databases, or networks</p> <p>APPLICATIONS</p> <p>The QuickPlot-DthDiff-DthData suite of software tools can be used for:</p> <p> * Flight testing and simulation projects</p> <p> * Manufacturing processes</p> <p> * Scientific research</p> <p> * Earth climate modeling and simulation</p> <p> * Retail transaction and delivery analysis</p> <p> * Economic market modeling</p>

<p>The aerospace industry uses model aircraft simulation systems to demonstrate and evaluate new computer hardware and software components for flight operations. Formal methods--mathematically based techniques--are used for verification and validation of new systems prior to implementation. By integrating and simulating new tools and methods in model flight control and air transportation systems, flight researchers provide the robust validation tools necessary for commercial system development.</p> <p>Developed at NASA's Armstrong Flight Research Center, the Quad TCM Simulation is a non-proprietary, non-sensitive aircraft Simulink&reg; flight-control-system-oriented model in MATLAB&reg; format. Derived from the TCM developed at NASA's Langley Research Center, Armstrong's Quad TCM Simulation components include flight control computers, sensors, actuators, and interconnects. Component models are the original TCM components with modifications to account for their multichannel nature, to allow for replacement with like components, and to enable testing and evaluation.</p> <p>BENEFITS</p> <p> * Non-proprietary and non-sensitive: Imposes no restrictions on reporting results</p> <p> * Ready to use: Fully integrated with flight control laws, redundancy management, multichannel interconnects, and transport class aircraft simulation</p> <p> * Easily modified: Enables flight control laws to be readily modified--including introduction of faults--thanks to the MATLAB Simulink environment</p> <p> * Speeds technology transfer: Accelerates dissemination and commercial acceptance of formal-methods-compliant tools and techniques</p> <p>APPLICATIONS</p> <p>This software is ideal for control research in realistic multichannel flight controls. In addition, it helps with learning about the complex effects of multichannel flight systems, including failure modes and effects, flight control system performance, etc. It is also useful for general simulation projects and flight system testing.</p> <p>MATLAB and Simulink are registered trademarks of The MathWorks, Inc.</p>

<p>Processing and plotting large amounts of data can be time consuming and expensive, particularly for data that specify time-varying values, so-called time history data. DthDiff--along with QuickPlot and DthData--helps manage several key operations for time history data, enable comparison of the time history files, and efficiently plot gigabytes to terabytes of data.</p> <p>A standalone command-line-driven utility program written in C, DthDiff compares time history files. In addition to configuring the nature of comparisons, users can specify a precision tolerance and perform a check for a specified number of significant digits. Alternatively, they can use absolute, relative, and percent tolerances to perform the comparison. Summary output also indicates the number of samples that fail specified tolerance tests.</p> <p>BENEFITS</p> <p>The QuickPlot-DthDiff-DthData suite of software tools offers several benefits:</p> <p> * Powerful: Processes large amounts of data from multiple sources and allows users to convert data files from one format to another</p> <p> * Efficient: Time-tags data files, enabling time-range processing of a selected parameter or set of parameters</p> <p> * Fast: Reads and plots data in a fraction of the time required for conventional data-plotting utilities</p> <p> * Simple: Offers a graphical user interface for command input and data plotting</p> <p> * Economical: Works without back-end processing systems, databases, or networks</p> <p>APPLICATIONS</p> <p>The QuickPlot-DthDiff-DthData suite of software tools can be used for:</p> <p> * Flight testing and simulation projects</p> <p> * Manufacturing processes</p> <p> * Scientific research</p> <p> * Earth climate modeling and simulation</p> <p> * Retail transaction and delivery analysis</p> <p> * Economic market modeling</p>

<p>Developers at NASA's Armstrong Flight Research Center have developed a software toolkit--dubbed Chapter 10 Tools--that is capable of reading data files originating from various onboard digital recorders that follow the Range Commanders Council Inter-Range Instrumentation Group (IRIG) 106 Chapter 10 Digital Recording Standard but use differing interpretations of that standard.</p> <p>The toolkit reads data files regardless of the vendor implementation of the source recorder, displays the data, and even identifies and corrects errors. Ultimately, it produces a data file that can be successfully processed post-flight.</p> <p>Chapter 10 Tools was developed in response to ongoing challenges researchers at Armstrong's Dryden Aeronautical Test Range faced when attempting to process data files originating from various vendors' digital recorders. As Chapter 10 experienced rapid growth as a technology standard for data recording, many digital recorder vendors began interpreting the standard differently--resulting in errors and variations (sometimes even between one vendor's different firmware versions of the same recorder). While some errors could be identified with Chapter 10 validation software, the type of error was not always apparent, making fixes problematic. These errors and variations can prevent software from reading and processing the data file, thereby effectively making the data unavailable.</p> <p>Chapter 10 Tools eliminates these challenges with a flexible software toolkit that gives users visibility into the data file's individual data packets, allowing for both manual and automatic correction of errors. An additional Telemetry Attributes Transfer Standard (TMATS) editor offers the ability to modify and add details to the TMATS file. Because aircraft personnel typically only include enough information in the TMATS portion of the Chapter 10 data file to allow for data recording, this leaves a gap in ground personnel's ability to process that data. So, the TMATS editor enables error correction and provides the ability to add the additional information needed to process the data.</p> <p>Chapter 10 Tools is now in widespread use at Armstrong's Dryden Aeronautical Test Range.</p> <p>BENEFITS</p> <p> * Diagnostic: Accurately identifies errors and variations in various Chapter 10 data files, as well as the error type</p> <p> * Flexible: Offers a flexible architecture enabling visibility into individual data packets</p> <p> * Easy to use: Autocorrects most errors, and makes manual error identification and correction simple and streamlined</p> <p>APPLICATIONS</p> <p>Chapter 10 Tools is ideal for:</p> <p> * NASA flight data processors needing to reconcile data between varying flight data recorders</p> <p> * Software developers looking to integrate error identification and correction capabilities into their Chapter 10 toolkits</p>

<p>Structural Analysis Routines (STARS) is an efficient, cost-effective, and unique computer program that analyzes a variety of practical engineering problems. The software is a fully integrated, multidisciplinary, finite-element-based, graphic-oriented analysis tool that combines individual modules to solve complex engineering problems. STARS can be used for a range of applications, including structural analysis, heat transfer, linear aerodynamics, and computational fluid dynamics (CFD) as well as coupled linear and CFD-based (aeroelastic, aeroacoustic, and aerothermoelastic) acoustics and aeroservoelastic analysis. Because of the tool's highly integrated nature, it has broad application across many engineering disciplines.</p> <p>BENEFITS</p> <p> * Efficient: Integrates general-purpose analysis modules for a range of multidisciplinary applications</p> <p> * Easy to implement: Utilizes standard FORTRAN language to run on a variety of computational platforms</p> <p> * Powerful: Processes large amounts of data for a finite-element-based, graphic-oriented linear and nonlinear analysis</p> <p>POTENTIAL APPLICATIONS</p> <p> * Aerospace engineering</p> <p> * Mechanical and civil engineering</p> <p> * Automotive design</p>

<p>This software program offers a reliable method for calculating theoretical fatigue crack growths that could lead to catastrophic structural component failures. The program builds upon and integrates Armstrong's proven half-cycle and closed-form aging theories and is especially accurate because it considers every half-cycle of loading spectra for specific structural components. This innovation is an improvement on traditional prediction software (and in particular on visual inspections) because it considers mini-amplitude stress loading and half-cycles based on the duty cycle of a particular component or structure.</p> <p>Developed to calculate the number of operational life flights for B-52B pylon hooks, the program and underlying theories can be applied to estimate the service life of any critical structural component. </p> <p>BENEFITS</p> <p> * Reliable: Predicts operational flight life of critical aerostructural components</p> <p> * Accurate: Considers a comprehensive suite of test data by counting every half-cycle of each random loading spectrum, including secondary mini-amplitude half-cycles that do not cross mean stress lines</p> <p> * Customized: Identifies potential structural problem areas and calculates the number of safe flights an aerostructure can make based on its particular duty cycle</p> <p> * Economical: Saves monetary costs associated with loss of expensive equipment due to component failures</p> <p> * Adaptable: Offers applicability to other industries, with modifications to the input model</p> <p>POTENTIAL APPLICATIONS</p> <p> * Spacecraft</p> <p> * Aircraft</p> <p> * Ships</p> <p> * Oil rigs</p> <p> * Windmills </p> <p> * Bridges</p> <p> * Oscillating industrial equipment used in mines and quarries</p> <p>HOW IT WORKS</p> <p>The Half-Cycle Crack Growth Computer Program is a powerful and practical tool for visualizing crack growth curves associated with critical stress points. It was designed to determine the number of safe operational flights an aircraft can make without structural component failures due to fatigue crack growth. The computer program was developed after two rear B-52B pylon hooks failed simultaneously during an Armstrong test operation. Subsequent examinations revealed that hook failure was caused by rapid crack propagation from existing micro cracks that had been masked by chrome-plated surfaces and thus were undetected during visual inspections.</p> <p>To obtain baseline data for use in the program, the critical structural components must be proof-load tested to determine the initial theoretical crack size based on fracture mechanics. Next, strain gauges are installed in the vicinity of stress concentration points and are calibrated to record the applied loads. After the failure-critical components are identified, stress analysis is performed for each component to establish the functional relationship between the applied load and the induced tangential stress at the critical stress point. The program reads the data and selects the maximum and minimum loads of each half-cycle of the random flight loading spectra. Program outputs are used to generate and display crack growth curves, providing a visual warning for preventing catastrophic structural failures.</p> <p>For the B-52B pylon hooks discussed above, crack growth curves were produced for each hook, allowing visual observation of the crack growth behavior during the entire air-launching or captive flight. The crack growth curves provided the visual knowledge that taxiing, takeoff, drop/landing, and sometimes gusts induced a major portion of the total crack growth per operation.</p> <p>Written in the C programming language, the program can be adapted for use in other industries by modifying the input model (i.e., data format load spectrum files) for the most expensive and mission critical components.</p> <p>WHY IT IS BETTER</p> <p>The program examines test data in a much more detailed fashion than other fatigue crack growth modeling software, counting every half-cycle of each random loading spectrum, so it is able to make better predictions about component life. By improving fatigue and failure predictions, the software provides safer flights and lower maintenance costs. Additionally, these predictions allow engineers to determine the critical points during operation that the majority of stress is placed on a particular component, which could allow for better component design that takes those specific forces into account.</p>

<p>This easy-to-use open source MATLAB&#174;- based software was first developed to give X-56A aircraft engineers a modeling tool to understand aeroservoelasticity. EZASE now introduces students and practicing engineers to aeroservoelastic phenomena in flexible structures. Useful for analysis and control design of flutter or gust-load alleviation, EZASE is applicable to ground vibration, cantilever loading, and wind tunnel testing.</p> <p>This finite element modeling and simulation tool for aeroservoelastic analysis of rectangular wings with trailing-edge control surfaces includes a tutorial on structural finite element modeling (FEM_Tutorial.m). The tutorial uses such elements as 12 degree-of-freedom (DOF) plates and 6 DOF beams. An aero tutorial (DLM_VLM_Tutorial.m) shows how to code doublet lattice and vortex lattice, with symmetry capability. Together, the finite element and aero tutorials can be used to compare to experimental studies, such as ground vibration testing, cantilever beam analysis, and wind tunnel testing. </p> <p>The primary code, EZASE.m, links structures and aero together in a commented way to produce a wing in flutter which can be controlled. The wing may include control surfaces, or they can be excluded. A state space model with control surface inputs and accelerometer outputs can be produced. This model is used to design a proportional-integral-derivative (PID) control system and is tested using margin studies and pole plots. Other visualization methods such as V-g plots (velocity versus g loads) determined using the K-method are also included.</p> <p>The code is commented for graduate and undergraduate students who want to know the basic concepts of medium-fidelity aeroservoelastic modeling. (Not all methods are coded to industry standards, but it is useful for basic understanding.) All of the details of the code are open sourced here and most is referenced at the top of the file to its source paper or book section. Two AIAA publications--one focusing on verification and validation (V&V) with experimental wind tunnel test and ground vibration test data--are also included.</p> <p>FEATURES</p> <p>* Produces models in seconds</p> <p> * Includes tutorial and references</p> <p> * Makes videos for intuitive understanding of gust/flutter dynamics</p> <p> * Enables easy modification of a full range of parameters</p> <p>MATLAB is a registered trademark of The Mathworks, Inc.</p>

The Structure Deformation Calculation Program is a computer program that will calculate slopes, deflections, and cross-sectional twist angles if applicable at strain-sensing stations on any structures based on the Ko Displacement Transfer Functions. By using this method, only a small number of strain sensors are required along strain-sensing line(s) on a structure. The program uses measured surface bending strains obtained at strain-sensing stations and structure geometrical properties as its inputs. Depending on structure type, the program will use the appropriate Ko Displacement Transfer Function. All structure types mentioned in the publications listed in the Technology Readiness / Software tab are covered in this program. The figures of different structure types will be included in the Additional Documentation in the General Information tab. The Displacement Theory is purely geometrical in nature, containing no material properties. The program will output time history slopes, deflections, maximum deflections, and cross-sectional twist angles if applicable, and depth factors if calculated. Users can use the time history deflections for plotting: deformed shapes of the structure at a certain time slice, three dimensional deformed shapes at multiple time slices, and deflections of each individual strain-sensing station. The calculated deflections of a structure can be studied and analyzed for monitoring the health of a structure to prevent catastrophic events.

<p>This multidisciplinary design analysis and optimization (MDAO) solution automates optimization tasks early in the design process according to a range of user-defined parameters, including factors such as cost, safety, and environmental impact. The tool provides a framework that enables several engineers to use multiple programs to globally optimize a model.</p> <p>This tool quickly streamlines optimization and design tasks by integrating disparate software packages--NASTRAN&#174;, ZAERO&#174;, Cart3D, FUN3D, MOMAT, etc.--in a cross-platform network environment. Designers can convert design variables to structural parameters and generate objective functions using either the built-in pre/post-processor or their own analyzer.</p> <p>FEATURES</p> <p> * Central executive module allows designers to choose input/output files and solution modules, determine the status of tasks, and select modules for output viewing and filtering.</p> <p> * Object-oriented framework integrates the analysis codes for multiple disciplines, rather than relying on one code to perform the analysis for all disciplines.</p> <p> * Modules calculate structural weight, stress, deflection, buckling, and more.</p> <p> * Graphical user interface can provide a single point of control for applications that run on a user's PC or for code that may reside on remote workstations or a computational cluster.</p> <p> * Use of existing tools and practices saves development time and resources.</p> <p> * With most of the code written in standard Fortran, it is easy to upgrade and incorporate new optimization technologies while integrating/adopting new state-of-the-art software.</p> <p>POTENTIAL APPLICATIONS</p> <p>Originally developed for preliminary design of subsonic, transonic, supersonic, and hypersonic aircraft, this innovative MDAO tool can be applied to other engineering fields, including:</p> <p> * Shipbuilding</p> <p> * Automotive</p> <p> * Engineering services</p> <p> * Packaging</p> <p> * Sporting equipment</p> <p>NASTRAN is a registered trademark of the National Aeronautics and Space Administration. ZAERO is a registered trademark of ZONA Technology, Inc.</p>