by Nancy Pekar
NASA Goddard
A little more than three years ago, the technology transfer office at NASA Goddard Space Flight Center developed an agreement that granted the Federal Highway Administration's Turner-Fairbank Highway Research Center (TFHRC) access to the Hilbert-Huang Transform (HHT) technology and expert advice from the inventor, Norden Huang (retired). Since then, Goddard's technology has played a key role in TFHRC scientists' analyses of traffic flow data, wind and traffic interaction with bridges, and damage detection in pavement and bridges. These analyses, which are performed for the Digital Highway Measurement (DHM) Project, are the first steps in a dramatic shift in the way state departments of transportation will be able to improve the safety and performance of the nation's highway infrastructure.
Dr. Huang began developing HHT in 1995 as part of his oceanography research at Goddard. Unlike precursor technologies, HHT provides an effective method for analyzing nonlinear and nonstationary signals while improving the accuracy of linear-and stationary-signal analysis. Because analytical measurements within many areas of science benefit from a quantitative measurement of nonlinear data, HHT is widely applicable to a broad range of fields, including medicine, electronics, the environment, and business. HHT was ideal for structural engineering analyses at TFHRC.
TFHRC conducts technology R&D to provide solutions to complex technical problems, thereby enhancing the safety and reliability of the U.S. highway transportation system. Dr. Huang met officials from TFHRC at a seminar, and discussions ensued on the potential use of HHT in highway research.
These discussions eventually led to the 2003 agreement developed, negotiated, and administered by Goddard's Innovative Partnerships Program office.
Under the agreement, TFHRC scientists collaborated directly with Dr. Huang to build an operational model of HHT for their own analyses and to build a knowledge base for using the HHT algorithms for the DHM project. This project uses a van driving at highway speeds to collect and analyze critical highway safety data, which can lead to better bridge and highway safety, design, and construction.
"The HHT has been a critical element for accurate analysis of data from some of the sensors on board the DHM van," explained TFHRC's Morton Oskard. "The capability being created in the van represents the beginning of a paradigm shift in the way states will view and be able to carry out their stewardship of the nation's highway infrastructure."
As a result of working with Goddard's HHT technology, TFHRC gained the ability to measure highway design performance, rate of deterioration, and remaining life, thus improving the performance of future highways and bridges.
TFHRC will be able to use these findings to improve future highway safety and contribute to improved quality of life.
For NASA, the agreement enhanced NASA's strategic technology objectives. As noted by Dr. Huang, "By sharing the HHT technology with TFHRC, NASA will also benefit by using the resulting knowledge to refine and further develop HHT and its use in other areas of research."
For example, stability analyses developed using HHT on vibration measurements at TFHRC are being used to benefit NASA research as well, particularly aero-elastic flight data at NASA Dryden Research Center.
A three-year agreement with TFHRC has enabled scientists to learn how to apply NASA Goddard Space Flight Center's HHT technology to analyses of traffic flow, wind and traffic interaction with bridges, and damage detection in pavement and bridges. (Click image to enlarge)
