Experimental study of nonlinear normal modes of vibration

• Grant number: 17/07057-9
• Support type: Scholarships in Brazil - Scientific Initiation
• Effective date (Start): October 01, 2018
• Effective date (End): September 30, 2019
• Field of knowledge: Engineering - Mechanical Engineering - Mechanics of Solids
• Principal Investigator: Samuel da Silva
• Grantee: Ana Cristina Neves Carloni
• Home Institution: Faculdade de Engenharia (FEIS). Universidade Estadual Paulista (UNESP). Campus de Ilha Solteira. Ilha Solteira , SP, Brazil

Abstract

The knowledge of the dynamical properties of mechanical and structural systems is important to understand the vibratory outputs from aircrafties, satellites until washing machines for designing purposes. Thus, the modal analysis is used to extract the modal parameters from the mass and stiffness matrix. The linear normal modes extracted by modal analysis have several interesting properties, as for instance, orthogonality, homogeneity, no multiple solutions, etc. However, if the system presents nonlinear regime of motion, the linear modal analysis fails. In this sense, the goal of the present project is to use the nonlinear modal analysis to identify the nonlinear normal modes. The nonlinear normal modes have different properties comparing with linear normal modes. Thus, this project intends to study and compare these properties and differences between the linear and nonlinear normal modes, respectively. The main goal is to discuss if it is possible to obtain a further mathematical framework between the approach using Volterra series to compute the High-Order Frequency Response Function (HOFRFs) based on Nonlinear Normal Modes. The present proposal presents the motivation, contributions and work plan to reach the research goal.