壓電薄膜感測器(Polyvinylidene fluoride, PVF2, PVDF)為一種壓電材料，利用其受到壓力或拉力時，產生的電壓變化，我們可量測結構構件的動態行為。
本文透過懸臂薄梁進行不同感測器與不同大小PVDF感測器，在時域以及頻域訊號的比較，而頻域比較包括了理論解、數值解與實驗所做出的結果，實驗結果顯示PVDF感測器對於結構的應變感測能力非常好。同時也利用PVDF來擷取鋼珠撞擊懸臂梁後的波源歷時，並使用此數據進行模擬，觀察實驗的暫態訊號與模擬之間的差異，比較過後發現兩者具有時間差，原因來自於實驗中固定端的夾持不完全，使整體頻率低於模擬，導致波長變長，產生時間差。

This study compares the strain sensor performance of strain gauge and different sizes of PVDF using a cantilever beam. The experimental results show that the PVDF sensor exhibits excellent measuring capabilities for structural dynamic responses. We also apply PVDF to measure a source wave from a steel ball impact. At the same time, another PVDF is placed as a receiver. The time history of the source wave obtained from the experiment is imported to finite element analysis to simulate the transient response of the receiver. By comparing the results at the receiver from the simulation and experiment, we found a time difference between these two. This could be due to incomplete clamping at the fixed end in the experiment. The clamping problem results in lower natural frequencies for the cantilever beam than those in the simulation. Lower natural frequencies mean longer wavelengths, leading to the time delay in the experiment compared to the simulation.

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[22] https://www.pitotech.com.tw/contents/en-us/p15406_0323.html