Ultra-Durable and Reliable High-k Textile Capacitors for Wearables and Robotics

Abstract

Emerging printed sensors and wearable technologies are creating a major impact in the area of health monitoring and robotics. The use of flexible and compact sensors that have wireless connectivity is a must in the Internet-of-Things era (IoT) which can provide personalized care and accurate decision-making capabilities to monitor vital signs and abnormalities in patient care. This work focuses on multipurpose wearable smart textile-based patches for monitoring biomedical health and physical activity. The patches have capacitive sensor elements that can capture critical information on the strength, frequency and duration between specific episodes of movements in the arms, legs and torso [1] as well as motion and proximity feedback in robotics applications. The performance of these extremely thin, light and elastic capacitive patches can be enhanced by use of silicone dielectric elastomer with Barium Titanate Oxide (BaTiO 3 /BTO) nano-particles. BaTiO 3 has a perovskite structure of the form ABO 3 that has many useful properties including high-k dielectric constant, piezoelectricity and ferroelectricity [2] . The grain size of BTO nanoparticles (50 nm and 500nm) has a profound effect in the elastomeric dielectric of the capacitive patches by changing the dielectric constant and incorporating piezoelectricity to the patches [3] . This work illustrates the important features of such composite capacitive patches and their potential for sensing motion, temperature and impact.