Application of Volterra series in nonlinear mechanical system identification and in structural health monitoring problems

• Autor(a) principal: Shiki, Sidney Bruce [UNESP]
• Data de Publicação: 2016
• Tipo de documento: Tese
• Idioma: eng
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: http://hdl.handle.net/11449/137761
• topic: Nonlinear structures; Structural health monitoring; Volterra models; Kautz filters; Nonlinear model updating; Estruturas não lineares; Monitoramento de integridade estrutural; Modelos de Volterra; Filtros de Kautz; Ajuste de modelos não lineares

Nonlinear structures are frequent in structural dynamics, specially considering screwed components, with joints, clearance or flexible components presenting large displacements. In this sense the monitoring of systems based on classical linear methods, as the ones based on modal parameters, can drastically fail to characterize nonlinear effects. This thesis proposed the use of Volterra series for nonlinear system identification aiming applications in damage detection and parameter quantification. The property of this model of representing the linear and nonlinear components of the response of a system was used to formulate damage features to make clear the need of nonlinear modeling. Also metrics based on the linear and nonlinear residues of the terms of the Volterra model were employed to identify parametric models of the structure. The proposed methodologies are illustrated in experimental setups to show the relevance of nonlinear phenomena in the structural health monitoring.