Abstract
Currently available perimeter-security systems use ground-buried fiber-optic sensors to detect objects on the ground surface, and some of them compare the observed signal patterns with those in a predefined library to identify specific types of objects. However, such qualitative approaches neglect a wealth of information contained in the measured signal. In this paper a more rational approach is presented that uses ground-buried distributed fiber-optic strain sensors with very high spatial and strain resolution to quantify the strain field induced by an object in contact with the ground surface. The contact interactions on the ground surface are calculated from the strain measurements using a mechanical soil model and inverse analysis algorithms similar to those used in image deblurring. The approach should enable a variety of applications where the knowledge of contact interactions on the ground surface is beneficial, from biodiversity survey, perimeter security, and weigh-in-motion systems to biomechanical applications and sports medicine.
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Data Availability Statement
All data are available upon request to the authors.
Acknowledgments
The authors would like to thank M. Schwager, P. Minder, P. Oberender, and A. Stoecklin (Institute for Geotechnical Engineering, ETH Zurich) for valuable discussions on the topic; R. Rohr and H. Buschor (Institute for Geotechnical Engineering, ETH Zurich) for their help in constructing the experimental setup; and A. Trabesinger for discussions on the manuscript and its linguistic review.
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Published In
Journal of Geotechnical and Geoenvironmental Engineering
Volume 145 • Issue 2 • February 2019
Copyright
©2018 American Society of Civil Engineers.
History
Received: Sep 5, 2017
Accepted: Jul 26, 2018
Published online: Dec 14, 2018
Published in print: Feb 1, 2019
Discussion open until: May 14, 2019
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