Analysis of linearity and frequency response of a novel piezoelectric flextensional actuator using a homodyne interferometer and the J1 - J4 method - Marçal, Luiz Antônio Perezi; Leão, José Vital Ferraz; Nader, Gilder; Higuti, Ricardo Tokio; Kitano, Cláudio; Silva, Emílio Carlos Nelli (IEEE Transactions on Instrumentation and Measurement, 2007)