Rail Flaw Imaging by Ultrasonic Synthetic Aperture Focus Techniques (SAFT)

Transverse Fissure in rail

Ultrasonic Synthetic Aperture Technique for internal flaw imaging

Wave mode compounding to dramatically  improve dynamic range and focus of flaw images

Wave mode compounding to dramatically  improve dynamic range and focus of flaw image

2D imaging of 20% H.A. natural Transverse defect in a rail

3D imaging of 10% H.A. simulated Transverse Defect in a rail

Funding:

Collaborators:

Purpose:

To enable quantitative, rather than qualitative rail flaw detection during manual verification of a defect detection. Current rail flaw verification and sizing is conducted by ultrasonic pulse-echo testing whose interpretation is highly operator-dependent. This leads to missed detections or inaccurate flaw sizing. There is a need to develop an imaging technique that can provide accurate and quantitative information on rail flaw type, orientation and size.

Synopsis:

The US has a "stop-and-confirm" rail inspection mode whereas indications of rail defects must be manually verified. UCSD is working on improved versions of techniques based on ultrasonic Synthetic Aperture Focus (SAF) to provide accurate 3D information of rail flaw type, orientation and size.  The improvements that are being implemented over conventional ultrasonic SAF techniques include: full matrix capture, wave mode structure weights, wave mode compounding, and real-time beamforming with GPU processing.

Selected Publications:

Liang, A., Sternini, S., Capriotti, M., and Lanza di Scalea, F., “Rail defect Imaging by Improved Ultrasonic Synthetic Aperture Focus Techniques,” Materials Evaluations, Special Issue on NDT of Railroads, Dr. Anish Poudel, ed., 77(7), pp31-940, 2019. 

Sternini, S., Pau, A, and Lanza di Scalea, F., “Minimum Variance Imaging in Plates Using Guided Wave Mode Beamforming,” IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control (IEEE-UFFC), in press, 2019.

Sternini, S., Liang, A.Y. and Lanza di Scalea, F., “Ultrasonic Synthetic Aperture Imaging with Interposed Transducer-Medium Coupling Path,” SHM International Journal, 18(5-6), pp. 1543-1556, 2019.

Hu, H., Zhu, X., Sternini, S., Lanza di Scalea, F., Xu, S., et. al. “Stretchable Ultrasonic Transducers for Three-Dimensional Imaging on Complex Surfaces,” Science Advances, 4(3), pp. 1-11, 2018. 

Lanza di Scalea, F., Sternini, S. and Nguyen, T., “Ultrasonic Imaging in Solids Using Wave Mode Beamforming,” IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control (IEEE-UFFC), 64(3), pp 602-616, 2017. 

Nguyen, T., Sternini, S., and Lanza di Scalea, F., “Advances In Ultrasonic Defect Detection and Imaging in Structures,” Proceedings 5th International Conference on Smart and Multifunctional Materials Structures & Systems (CIMTEC) – Symposium P, Perugia, pp. 1-5, June 5-9, 2016. 

Nguyen, T., Sternini, S., and Lanza di Scalea, F., “3D Ultrasonic Imaging Applications on Rails,” Proceedings of the ASME Joint Rail Conference (ASME-JRC), paper no. JRC2016-5760, pp. 1-10, Columbia, SC, April 12-15, 2016. 

Phillips, R., Lanza di Scalea, F., Nucera, C., Rizzo, P., Al-Nazer, L., “Ultrasonic Tomography for Rail Flaw Imaging,” CD-ROM Proceedings of the 2014 ASME Joint Rail Conference, Colorado Springs, CO, pp. 1-10, April 2-4, 2014. 

 Lanza di Scalea, F., Rizzo, P., Salamone, S., Bartoli, I., Al-Nazer, L., “Ultrasonic Tomography for Three-Dimensional Imaging of Internal Rail Flaws: Proof-of-principle Numerical Simulations,” Transportation Research Record: Journal of the Transportation Research Board, no. 2374, Washington DC, pp. 162-168, 2013.

Lanza di Scalea, F., Rizzo, P., Salamone, S., Bartoli, I. and Al-Nazer, L., “Ultrasonic Tomography for Three-Dimensional Imaging of Internal Rail Flaws: Proof-of-principle Numerical Simulations,” CD-ROM Proceedings of the 92th Annual Meeting of the Transportation Research Board, Washington DC, January 2013.