When ultraviolet light illuminates on polarized PLZT ceramic, a large voltage can be generated between the electrodes due to the anomalous photovoltaic effect. The shape control of flexible shell can be realized by using hybrid photovoltaic/piezoelectric actuation. In this paper, a novel non-contact deflection closed-loop control model of cantilever beam based on hybrid photovoltaic/piezoelectric actuation can be proposed. The photovoltage of PLZT ceramic irradiated by ultraviolet light is applied to drive PVDF actuator. The closed-loop control equations of deflection of cantilever beam is derived based on the mathematical model of PLZT ceramic with coupled multi-physics fields and the constitutive model of cantilever beam. Then, parameters of deflection control equations of cantilever beam during illumination phase and light off phase are identified through the deflection static experiment. After that, the deflection closed-loop control experiment of cantilever beam based on hybrid photovoltaic/piezoelectric actuation mechanism is carried out to verify the control model. The experimental results show that the deflection of cantilever beam with a simple on-off control method can achieve the target value by applying UV light to PLZT ceramic. It also should be noted that, the deflection curve of cantilever beam illuminated by strong UV light has an undesirable fluctuation.
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