The effect of the location of piezoelectric patches on the sensing, actuating and energy harvesting properties of a composite plate

The paper investigates the effect of the location and size of piezoelectric patches in a composite multilayer plate on the energy input/output when the plate acts as a sensor, actuator, or an energy harvester. It is shown that whether the process is low frequency (static) or higher frequency, for any size of the piezoelectric patches there is always one location where the energy input/output reaches a maximum. In addition, it is shown that for a dynamic vibrational loading the energy input/output is extremely sensitive to the operating frequency. If the operating frequency is just below the systems resonant frequency (corresponding to the length and position of the patches) the best location for the maximum energy input/output is significantly different from the best location when the operating frequency is just above the systems resonant frequency. In other words, a very small change in the systems operating frequency in the vicinity of the resonance frequency can make a significant effect on the best locations for the patches for the energy input/output.