QUICK FACTS
Test engineers at American Association of Railroads (AAR) Transportation Test Center use PV-WAVE to integrate graphics and analysis in order to find out more about metal strength. Railcar-mounted sensors collect the data; it is converted into a custom binary format and stored on huge data servers. PV-WAVE is later used for post-analysis.

THE PROBLEM
Test engineers in Pueblo, Colorado, use one of the world's largest hydraulic vibration platforms to help design safer trains. As the platform lifts and shakes prototype train cars, some weighing several tons, these engineers at the American Association of Railroads (AAR) Transportation Test Center study the metal strength of the passenger trains of tomorrow.

AAR needed a fast and flexible way to analyze the gigabytes of complex train car test data they collect, and visualize the results so that the engineers can optimize the train designs. Due to the sheer volume of data, high-end graphics were required to effectively analyze the information, and due to the nature of the data, powerful time series functionality was a must.

THE SOLUTION
AAR turned to PV-WAVE from Visual Numerics to solve their analysis problem. Using PV-WAVE visual data analysis (VDA) software from Visual Numerics with data acquisition equipment and workstations from Hewlett-Packard®, AAR engineers collect as much as 30 gigabytes of data from one metal fatigue experiment.

After hundreds of railcar-mounted sensors collect the data, they are converted into a custom binary format and stored on huge data servers for future analysis.

The value of this work depends on the quality of the data. At the high data-collection rates used in these studies, it's not uncommon to miss critical data samples, and because different instruments represent experimental values differently, the data must be scaled and normalized into a common range so values can be compared. This process of scaling data, converting them into engineering units and interpolating missing values is the linchpin of a successful experiment.

After the data is collected, checked and stored, post-analysis begins. Much post-analysis work involves time-series analysis like frequency domain and vibration analysis. PV-WAVE provides a variety of powerful functions for time-series analysis in single or multiple dimensions, including fast Fourier transformations, filtering, power-spectrum estimation and related functions like curve-fitting and interpolation.

The AAR engineers also use statistic functions like averages, covariance, correlation and regression analysis to assess the test results, comparing design parameters with railroad safety standards. And because most research require s some custom analysis, PV-WAVE gives engineers the flexibility to build custom functions.

Advanced computer graphics are another key part of the post-analysis process because they help engineers make research discoveries that might otherwise have been missed. For most of the research, AAR engineers use interactive 2D plots and contours. For example, plots showing stress versus time or color contours showing stress distribution over a region can easily be produced in PV-WAVE, even for very large data sets. To help make even faster discoveries, however, AAR engineers rely on PV-WAVE's more advanced graphics.

RETURN ON INVESTMENT
Visual data analysis with PV-WAVE helps AAR engineers make more discoveries faster because of the power that integrated graphics and analysis bring to the desktop. And, thanks to

PV-WAVE's easy-to-use menu and icon interface, users don't have to be computer scientists. This lets researchers spend more time on research and less time learning how to use the software.

For AAR engineers, PV-WAVE is a cost-effective solution to a wide variety of post-analysis needs. These benefits translate into productivity -[-more quality work done in less time and results that can easily be shared with colleagues. "With PV-WAVE, we spend less time reducing our data and more time interpreting results. We can do in minutes what used to take days," Higgins concluded.

WORLD CLASS PRODUCTS, SERVICES, AND SUPPORT
Visual Numerics has provided technical software solutions for numerical analysis and visualization for over 30 years. The company's software products help users understand complex data from a variety of sources and build business-critical applications. Visual Numerics offers two product lines: the IMSL® Numerical Libraries for powerful mathematical and statistical analysis and the PV-WAVE® visual data analysis development environment. Visual Numerics also offers customized consulting services for applications that involve mathematical, statistical, or visual data analysis to meet today’s business analytical needs.