Ultrastretchable Strain Sensors Using Carbon Black‐Filled Elastomer Composites and Comparison of Capacitive Versus Resistive Sensors

Abstract The advent of soft robotics has led to the development of devices that harness the compliance and natural deformability of media with nonlinear elasticity. This has led to a need of batch‐manufacturable soft sensors that can sustain large strains and maintain kinematic compatibility with the systems they track. In this article, an approach to address this challenge is presented with highly stretchable strain sensors that can operate at strains up to 500%. The sensors consist of a carbon black‐filled elastomer composite that is batch manufactured using film‐casting techniques and CO 2 laser ablation. This process facilitates the rapid multilayered fabrication of both capacitive and resistive sensing elements. When measuring capacitance, these sensors exhibit high linearity ( R 2 = 0.9995), low hysteresis under cyclic loading with varying strain amplitude (50–500%), and high repeatability (≥10 4 cycles). The sensors possess gauge factors of 0.83–0.98 in capacitive mode and 1.62–3.37 in resistive mode.