Piezoelectric Material Characterisation Using the Finite Element Model Updating Method

Piezoelectric materials allow for the transformation of mechanical strain energy into electrical energy and vice versa. These materials can either be found in nature or manufactured and they are used in a breadth of engineering applications such as power harvesting and smart sensing [1, 2]. Due to the increase in interest to better understand their behaviour, their more accurate material parameters determination has become increasingly important. In this paper, a numerical framework for piezoelectric material characterisation is proposed. The approach is based on experimentally obtained electric impedance phase diagrams where a cubic specimen is subjected to a voltage pulse that generates its mechanical and voltage oscillation with damping. The obtained resonance frequencies and their amplitude are then used as target values for seeking the material parameters using the Finite Element Model Updating method (FEMU). A series of dynamic FEM analyses are performed using the opensource software MoFEM [3] while changing the material input parameters between analyses realisations to minimise the differences between numerical and experimental resonance. The material parameter calibration is automated by using optimisation algorithms found in open-source libraries in python. The proposed framework is aimed to be used to aid new piezoelectric material technologies where more complex structures are involved