Dinâmica não linear e controle de um sistema vibratório modelado com memória de forma e, excitado por fontes de energia do tipo ideal e não ideal

• Ano de defesa: 2007
• Autor(a) principal: Piccirillo, Vinícius [UNESP]
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Estadual Paulista (Unesp)
• Palavras-chave em Português: Shape memory; Perturbations techniques; Ideal and non - Ideal systems; Sommerfeld effect; Linear feedback control; Engenharia mecanica; Memória de forma; Técnicas de perturbação; Sistemas ideais e não ideais; Efeito Sommerfeld; Controle ótimo
• Link de acesso: http://hdl.handle.net/11449/136707; http://www.athena.biblioteca.unesp.br/exlibris/bd/cathedra/21-03-2016/000545779.pdf

This work concerns of three parts, in the first we will make the study of the dynamical of a single - degree of freedom oscillator, which consist of a mass connected to a shape memory element and a dashpot, where the system harmonically excited (ideal source). An analytical solution for the system stationary oscillations is obtained by perturbations method, where was used the method of multiple scales. Due to this solution one can observe nonlinear phenomena trough of frequency - response curves. Besides, conditions for the system stability and the existence of saddle - node bifurcations are also obtained. In the second part show the computational and analytical study of the nonlinear dynamic behavior of the SMA oscillator, excited by a non ideal source - an unbalanced direct current electric motor of limited power. A problem whose mathematical model represents a simplified system (the characteristic of the motor in stationary state). It adopts the Lagrange formularization to deducing the equations of motion. Regular and irregular (chaotic) behaviors depend of the physical parameters and can be observed when a numerical integration is performed. The analytical solution is obtained using the averaging method, where due to this solution on can observe typical non-ideal phenomena like the amplitude motion dependency to the frequency of the excitation (Sommerfeld effect). The third part is dedicated to the application and performance of the linear feedback control for the suppressing of the chaotic motion of an ideal and non ideal system, theses systems are numerical studied.