Department of Structural Mechanics, University of Granada; ETS Ingenieros de Caminos, Severo Ochoa s/n, 18071 Granada, Spain.
Sensors (Basel). 2017 Jun 15;17(6):1402. doi: 10.3390/s17061402.
Torsion mechanical waves have the capability to characterize shear stiffness moduli of soft tissue. Under this hypothesis, a computational methodology is proposed to design and optimize a piezoelectrics-based transmitter and receiver to generate and measure the response of torsional ultrasonic waves. The procedure employed is divided into two steps: (i) a finite element method (FEM) is developed to obtain a transmitted and received waveform as well as a resonance frequency of a previous geometry validated with a semi-analytical simplified model and (ii) a probabilistic optimality criteria of the design based on inverse problem from the estimation of robust probability of detection (RPOD) to maximize the detection of the pathology defined in terms of changes of shear stiffness. This study collects different options of design in two separated models, in transmission and contact, respectively. The main contribution of this work describes a framework to establish such as forward, inverse and optimization procedures to choose a set of appropriate parameters of a transducer. This methodological framework may be generalizable for other different applications.
扭转机械波具有表征软组织剪切刚度模量的能力。基于这一假设，提出了一种基于压电的发射器和接收器的设计和优化方法，以产生和测量扭转超声波的响应。所采用的过程分为两个步骤：（i）开发有限元方法（FEM）以获得发送和接收波形以及先前经过半解析简化模型验证的几何形状的共振频率，以及（ii）基于稳健检测概率（RPOD）估计的设计概率最优性准则，以最大程度地检测基于剪切刚度变化定义的病理学。本研究在两个单独的模型（分别为传输和接触模型）中收集了不同的设计选项。这项工作的主要贡献是描述了一种建立这种正向、逆向和优化程序的框架，以选择一组合适的换能器参数。这种方法框架可能适用于其他不同的应用。
