Piezoresistive sensors, with polymer matrices and conductive nanoparticles, are a relatively new addition to the sensor class, with the potential to transform such fields as wearable sensors and the internet of things. The unusual inverse piezoresistive behavior of the sensors has been modeled using quantum tunneling and percolation theory. However, the impact of the distribution of conductive particles in the matrix, and specifically their relative orientation, has not been well studied. The initial and deformed distribution of orientations greatly influences the sensor behavior, since the quantum tunneling model is highly sensitive to the polymer gaps between nanoparticles; the evolution of these gaps under deformation is strongly dependent upon the relative orientation of neighboring particles, and determines electron transport properties, and overall sensor response. In this paper a simple analytical model for isotropic orientation distribution and subsequent Poisson-based gap evolution is compared with a more sophisticated finite element and random resistor network analysis. The new numerical model was able to explain previously unexplained physical behavior and is used to design sensors with specific desired characteristics. The appropriateness of the previously assumed percolation behavior is also examined via the model and generalized effective medium theory.

具有聚合物基体和导电纳米粒子的压阻传感器是传感器类别中相对较新的一种，具有改变可穿戴传感器和物联网等领域的潜力。已经使用量子隧穿和渗流理论对传感器的异常反压阻行为进行了建模。然而，尚未充分研究基质中导电颗粒的分布，特别是它们的相对取向的影响。方向的初始和变形分布极大地影响了传感器的行为，因为量子隧穿模型对纳米粒子之间的聚合物间隙非常敏感；这些缝隙在变形下的演化在很大程度上取决于相邻粒子的相对取向，并决定电子的传输特性，和整体传感器响应。在本文中，将用于各向同性取向分布和随后基于泊松的间隙演化的简单分析模型与更复杂的有限元和随机电阻器网络分析进行了比较。新的数值模型能够解释以前无法解释的物理行为，并用于设计具有特定所需特性的传感器。还通过模型和广义有效介质理论来检验先前假定的渗滤行为的适当性。新的数值模型能够解释以前无法解释的物理行为，并用于设计具有特定所需特性的传感器。还通过模型和广义有效介质理论来检验先前假定的渗滤行为的适当性。新的数值模型能够解释以前无法解释的物理行为，并用于设计具有特定所需特性的传感器。还通过模型和广义有效介质理论来检验先前假定的渗滤行为的适当性。