This paper presents development of a three dimensional finite element model for simulations of a conformable piezoelectric sensor utilizing COMSOL Multiphysics. The sensor has a multi-layer structure composed of four circular piezoelectric elements arranged in an array structure laminated on a soft substrate and is capable of providing a strain mapping of soft tissue surfaces for spatiotemporal biokinematic assessment of the facial skin. Here, we provide the finite element method (FEM) for the sensor to predict its electromechanical behavior. This paper studies the effect of the design parameters such as dimensions of the piezoelectric sensor and the substrate on voltage sensitivity and sensor compliance. The FEM model is established to understand the underlying physics and guide the mechanical characterization of the system. The developed model is experimentally verified through two series of tests. The first set of tests involve comprehensive in vitro mechanical testing to provide accurate measurements of strain during compression, stretching, and bending. The second set of tests present in vivo experiments on healthy and amyotrophic lateral sclerosis subjects. The experimentally verified FEM model provides a detailed insight into analyzing the response of the sensor which establishes new design rules for next generations of conformable piezoelectric sensors.

本文介绍了如何利用 COMSOL Multiphysics 开发一个三维有限元模型，用于仿真贴合压电传感器。该传感器具有多层结构，由四个圆形压电元件组成，排列成阵列结构，层压在软基板上，能够提供软组织表面的应变图，用于面部皮肤的时空生物运动学评估。在这里，我们为传感器提供了有限元方法 (FEM) 来预测其机电行为。本文研究了压电传感器和基板尺寸等设计参数对电压灵敏度和传感器顺应性的影响。建立 FEM 模型是为了了解基础物理并指导系统的机械特性。开发的模型通过两个系列的测试进行了实验验证。第一组测试涉及全面体外力学测试，可准确测量压缩、拉伸和弯曲过程中的应变。第二组测试针对健康和肌萎缩侧索硬化受试者进行体内实验。经过实验验证的 FEM 模型提供了对传感器响应分析的详细见解，为下一代可适配压电传感器建立了新的设计规则。