Application of a stochastic version of the restoring force surface method to identify a Duffing oscillator

Luis Gustavo Giacon Villani (1) , Samuel da Silva (1) , Americo Cunha Jr (2)

1 UNESP - Universidade Estadual Paulista Júlio de Mesquita Filho = São Paulo State University
2 UERJ - Universidade do Estado do Rio de Janeiro [Brasil] = Rio de Janeiro State University [Brazil] = Université d'État de Rio de Janeiro [Brésil]

This work deals with the identification of stochastic parameters in a nonlinear single degree-of-freedom system. For this purpose, a stochastic version of the restoring force surface method is proposed and used to identify the parameters of a clamped-free beam, with nonlinear effects induced by the presence of a magnet near to the free extremity. This system recalls a Duffing oscillator, which is used as mechanical-mathematical model. In order to validate the obtained stochastic model, experimental and theoretical responses are compared in time and frequency domains, taking into account a probabilistic band of confidence. The results show that obtained stochastic model adequately predict the beam's vibration responses, which ensure the robustness of identification of a stochastic model.

Domaines: Vibrations [physics.class-ph]; Probabilités [math.PR]; Statistiques [math.ST]; Mécanique des structures [physics.class-ph]; Mécanique des solides [physics.class-ph]; Génie mécanique [physics.class-ph]

Luis Gustavo Giacon Villani, Samuel da Silva, Americo Cunha Jr. Application of a stochastic version of the restoring force surface method to identify a Duffing oscillator. First International Nonlinear Dynamics Conference (NODYCON 2019), Feb 2019, Rome, Italy. ⟨hal-02095987⟩