Graphene and Liquid Metal Integrated Multifunctional Wearable Platform for Monitoring Motion and Human–Machine Interfacing

Abstract
Motion sensors are an essential component of many electronic systems. However, the development of inertial motion sensors based on fatigue-free soft proof mass has not been explored extensively in the field of soft electronics. Nontoxic gallium-based liquid metals are an emerging class of material that exhibit attractive electromechanical properties, making them excellent proof mass materials for inertial sensors. Here, we propose and demonstrate a fully soft laser-induced graphene (LIG) and liquid metal-based inertial sensor integrated with temperature, humidity, and breathing sensors. The inertial sensor design confines a graphene-coated liquid metal droplet inside a fluidic channel, rolling over LIG resistive electrode. The proposed sensor architecture and material realize a highly mobile proof mass and a vibrational space for its oscillation. The inertial sensor exhibits a high sensitivity of 6.52% m-1 s2 and excellent repeatability (over 12 500 cycles). The platform is fabricated using a scalable, rapid laser writing technique and integrated with a programmable system on a chip (PSoC) to function as a stand-alone system for real-time wireless monitoring of movement patterns and the control of a robotic arm. The developed printed inertial platform is an excellent candidate for the next-generation of wearables motion tracking platforms and soft human-machine interfaces.

Citation
Babatain, W., Buttner, U., El-Atab, N., & Hussain, M. M. (2022). Graphene and Liquid Metal Integrated Multifunctional Wearable Platform for Monitoring Motion and Human–Machine Interfacing. ACS Nano. https://doi.org/10.1021/acsnano.2c06180

Acknowledgements
Authors acknowledge generous support of King Abdullah University of Science and Technology.

Publisher
American Chemical Society (ACS)

Journal
ACS Nano

DOI
10.1021/acsnano.2c06180

PubMed ID
36201180

Additional Links
https://pubs.acs.org/doi/10.1021/acsnano.2c06180

Permanent link to this record