In this paper, an auto-tuning piezoelectric energy harvester (PEH) based on the cantilever plate is presented by attaching a box to each corner of the free sides and placing a ball in each box. The prototype and supporting experimental fixtures were designed and manufactured. A series of hammering experiments are carried out to measure the natural frequency of the device according to different whole centroid position of the two balls. Seven excitation frequencies are selected to perform auto-tuning experiments, respectively. The two balls roll automatically to make the natural frequency of the structure consistent with the excitation, thereby resonating. The device is subjected to sweeping experiments. It can be seen from open circuit voltage-frequency and power-frequency diagrams that the auto-tuning PEH has a wider work frequency band as TFB and outputs higher voltage and power compared to cases where balls are fixed.

中文翻译：

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盒装球自动调谐压电能量采集器的实验研究

在本文中，提出了一种基于悬臂板的自整定压电能量收集器（PEH），方法是在每个自由边的每个角上附加一个盒子并将球放置在每个盒子中。设计并制造了原型和辅助实验装置。根据两个球的整个重心位置的不同，进行了一系列锤击实验以测量设备的固有频率。选择七个激励频率分别执行自动调谐实验。两个球自动滚动以使结构的固有频率与激励一致，从而产生共振。该设备进行了广泛的实验。