Piezo films with adjustable anisotropic strain for bending actuators with tunable bending profiles

We present a method to produce in-plane polarized piezo films with a freely adjustable ratio of the strains in orthogonal in-plane directions. They can be used in piezo bending actuators with a tunable curvature profile. The strains are obtained as mean strains from a periodic polarization pattern produced by a suitable doubly interdigitated electrode structure. This mechanism is demonstrated for several examples using PZT sheets. We further discuss how this tuning and the parameters of the electrode layout affect the overall magnitude of the displacement.
Comment: Presentation improved, minor fixes, appendix added. Final version published in SMS. 15 pages, 6 figures