Dynamic analysis of a new piezoeletric flextensional actuator using the J1-J4 optical interferometric method - Marçal, Luiz A P; Leão, José V F; Nader, Gilder; Silva, Emílio Carlos Nelli; Higuti, Ricardo Tokio; Kitano, Cláudio (International Congress and Exposition on Noise Control Engineering, 2005)