Standard Article

Nonlinear Features for SHM Applications

Signal Processing

  1. Jonathan M. Nichols1,
  2. Michael D. Todd2

Published Online: 15 SEP 2009

DOI: 10.1002/9780470061626.shm049

Encyclopedia of Structural Health Monitoring

Encyclopedia of Structural Health Monitoring

How to Cite

Nichols, J. M. and Todd, M. D. 2009. Nonlinear Features for SHM Applications. Encyclopedia of Structural Health Monitoring. .

Author Information

  1. 1

    US Naval Research Laboratory, Washington, DC, USA

  2. 2

    University of California, Department of Structural Engineering, San Diego, CA, USA

Publication History

  1. Published Online: 15 SEP 2009


In structural health monitoring, it is often the case that the dynamics of the structure being monitored are appropriately described by a nonlinear model. The statistical properties of the structural response data are therefore different from those contained in a linear structure's response. Taking these properties into account when computing damage-sensitive features results in a more powerful approach to assessing damage presence, magnitude, location, and type over methods that rely on linear statistical properties. This article describes a variety of ways in which nonlinearity appears in structural dynamics and reviews a number of strategies for incorporating nonlinearity in the feature-extraction process.


  • structural health monitoring;
  • nonlinearity;
  • phase space;
  • surrogates;
  • higher-order spectra;
  • harmonics