Increasing the safety demands of various progressively complex structures (e.g., in aerospace, automotive engineering, and wind power technology) and the parallel goal of reducing inspection costs set new objectives in the field of ultrasonics and guided elastic wave measurements. The focus is to deliver applicable sensors attached permanently to a particular structure for on-demand inspections. Piezoelectric fiber patches (PFPs) are known as lightweight and structure-conforming transducers for guided elastic wave generation and detection. We propose a new PFP concept combining advantages of different previous designs. With the new approach, a user can switch between a Lamb wave and a shear horizontal wave excitation by partially changing the polarity of the transducer electrodes. After summarizing the existing PFP variants, the new concept is introduced and experimentally verified by a three-dimensional laser Doppler vibrometer visualization of excited waves. Moreover, the first prototype of the new PFP transducer is presented.

中文翻译：

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一种模式可切换的引导弹性波换能器

各种逐渐复杂的结构（例如，航空航天、汽车工程和风力发电技术）的安全需求的增加以及降低检查成本的并行目标为超声波和引导弹性波测量领域设定了新的目标。重点是提供永久连接到特定结构的适用传感器，以进行按需检查。压电纤维贴片 (PFP​​) 被称为用于引导弹性波生成和检测的轻型且结构一致的换能器。我们提出了一种新的 PFP 概念，结合了不同先前设计的优点。使用新方法，用户可以通过部分改变换能器电极的极性，在兰姆波和横波激发之间切换。在总结了现有的 PFP 变体之后，引入了新概念，并通过激发波的三维激光多普勒振动计可视化进行了实验验证。此外，还展示了新型 PFP 换能器的第一个原型。