Triple-shape memory, magneto-response, and piezo-resistive flexible composites: multiple-sensing and switchable actuating

Abstract

Flexible strain sensors made of conductive composites provide an opportunity for monitoring human motions and external stimuli. However, it is still in pursuit to fabricate multifunctional strain sensors with shape memory effects to further broaden the practical applications. Herein, we designed and fabricated a high-temperature liquid metal–based magneto-resistive strain sensor with a triple-shape memory effect, stimulus-dependent conductivity, and magnetically driven property. The shape memory effect endowed the sensor with the ability to adapt its morphology to detect and fix on the objects with an arbitrary shape. The stimulus-dependent conductivity caused the sensor to generate a corresponding electrical signal when it detected any human motion and magnetic field. The magnetically driven properties broadened the application of the sensor, such as a smart gripper. Therefore, this multifunctional flexible strain sensor could be a good candidate for future intelligent electronics such as e-skins, soft robotics, morphing structures, and biomedical devices.