Damage detection in an uncertain nonlinear beam

Author(s)

Giacon Villani, Luis Gustavo ; da Silva, Samuel ; Cunha, Americo, Jr. ; Vestroni, F ; Romeo, F ; Gattulli, V

• Document type: Journal article
• Source: X INTERNATIONAL CONFERENCE ON STRUCTURAL DYNAMICS (EURODYN 2017); v. 199, p. 6-pg., 2017-01-01.

Abstract

The present paper proposes the use of discrete time Volterra series expanded with Kautz filters for predicting the experimental response of a nonlinear beam, taking into account uncertainties that are inherent to the system. Nonlinear behavior is simulated considering large amplitude of vibration in a clamped-free beam, with a magnet near the free end to cause cubic stiffness effect. The Volterra kernels and Kautz functions are estimated in a stochastic way, where the limits of confidence are established to the system response and used as a reference model to detect damage. The detection approach is based on a nonlinear stochastic index and hypothesis test, considering different levels of simulated damage, associated with loss of mass. The results have shown that considering the uncertainties when identifying the model is very important in the process of damage detection and the nonlinear metric proved to be more appropriated to describe the system response with better results mainly in the nonlinear regime of motion. (C) 2017 The Authors. Published by Elsevier Ltd. (AU)

• FAPESP's process: 12/09135-3 - Structural health monitoring in nonlinear mechanical systems through Volterra models
• Grantee: Samuel da Silva
• Support Opportunities: Research Grants - Young Investigators Grants
• FAPESP's process: 15/25676-2 - Robust damage detection in uncertain nonlinear systems
• Grantee: Luis Gustavo Giacon Villani
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)
• FAPESP's process: 14/02971-6 - Application of Volterra series in time-variant nonlinear models
• Grantee: Rafael de Oliveira Teloli
• Support Opportunities: Scholarships in Brazil - Scientific Initiation