Periodic Cellular Piezoelectric Sensors and Actuators for Frequency Based Wave Steering

所提出的研究的目的是调查，开发，优化，制造和测试的一个全新的类的致动器和传感器的结构健康监测（SHM）。提出周期性蜂窝配置作为有效手段，以提供具有强的、频率依赖的方向特性的致动器和传感器，其允许通过激励频率的简单扫描来发生波束转向。波束转向是通过利用阵列的周期性和其组件的同时致动所产生的干涉现象来实现的。这种干涉现象产生具有频率相关的方向特性的波，其允许扫描区域或体积，以及通过简单的频率扫描聚焦声能。这一概念在超声波和导波检测的致动器和传感器设计中引入了范式转变。硬件复杂性的大幅降低将允许传感器/致动器的小型和微型封装，其应用可以扩展到SHM领域之外。

The objective of the proposed research is the investigation, development, optimization, manufacturing and testing of a completely novel class of actuators and sensors for structural health monitoring (SHM). Periodic cellular configurations are proposed as effective means to provide actuators and sensors with strong, frequency dependent directional characteristics, which allow beam steering to occur through a simple sweep of the excitation frequency. Beam steering is achieved by exploiting interference phenomena generated by the periodicity of the array and the simultaneous actuation of its components. Such interference phenomena produce waves with frequency dependent directional characteristics which allow scanning of an area or volume, as well as focusing of the acoustic energy through a simple frequency sweep. This concept introduces a paradigm shift in the design of actuators and sensors for ultrasonic and guided wave inspection. Major reduction in hardware complexity will allow small and micro packaging of sensors/actuators, whose application can be extended well beyond the filed of SHM.