Design of Elastomer-Based Piezoresistive Sensors: Materials, Structural Aspects, and Prospects

Elastomer-based piezoresistive sensors are an impactful and promising means of monitoring biological motion, tracking biosignals, and measuring the mechanical collision of physical stimuli in robots or machines. Piezoresistive behavior is generally realized when conductivity is imparted to elastomers, which results in resistivity changes by an external force that induces elastic deformations. Piezoresistive behavior of an elastomer can be achieved by mixing or coating the elastomer with a conductive material, thereby forming a composite structure. In this review, the conductive and elastic components that may determine the performance of a sensor are introduced. Conductive materials are classified into metal fillers, carbon allotropes, and hybrid materials, while elastic structures are classified into nonperiodic/periodic, hierarchical, and textile-based formations. Then, this comprehensive review focuses on textile-based structures for flexible applications, emerging challenges, potential strategies, and finally, the proposed hybrid mechanisms.