Shape Morphing Wearable For Regulating the Nervous System Through Breathing

Abstract

This project addresses the gap in current stress-regulation treatments by developing a smart textile wearable that integrates shape-morphing materials and body monitoring sensors to regulate the nervous system through conscious breathing. Anxiety, recognized as the leading chronic stress-related disorder globally by the World Health Organization, often remains inadequately treated due to the lack of advanced mental health solutions which fail to integrate into daily life, resulting in underutilization and insufficient awareness. Consequently, existing solutions are either focused solely on body monitoring or haptic feedback, typically involving bulky and noisy electromechanical systems. This project aims to bridge this gap by combining both elements into a discreet, non-intrusive abdominal wearable, designed for everyday use to enhance individual awareness of anxious conditions and facilitate self-management.

By utilizing Shape Memory Alloys (SMAs) for their advantageous power-to-weight ratio and ease of integration into textiles, this project explores their potential to simulate diaphragmatic breathing rhythms, aiding users in managing anxiety. Guided by the Material Driven Design (MDD) methodology, the project synthesizes theoretical and empirical research to develop a wearable prototype that accurately replicates breathing rhythms through SMA, monitors heart rate, and ensures user comfort and a soothing experience. Experimental studies with 0.5mm NiTiCu SMAs in zigzag configurations demonstrate the feasibility of reducing response time and controlling expansion movements at a high deformation strain, enhancing the simulation of breathing rhythms. A new SMA re-training method was identified, which conserves time, effort, and energy without necessitating high temperatures above 500ºC.

User studies indicate a strong preference for active engagement in haptic breathing guidance, which enhances focus and personal connection to the device. The wearable’s slow, organic expansion-contraction movements on the abdomen closely mimic natural diaphragmatic breathing, facilitating synchronization and promoting a sense of calm. The prototype’s dual association with medical and personal contexts, combined with its portability, supports versatile use across different settings and postures, thereby contributing to a positive user experience. The findings demonstrate the device’s efficacy in heightening user awareness and managing high stress, presenting a promising solution for health applications. This project provides significant insights into the integration of SMAs and smart textiles for mental health applications, presenting a noiseless, lightweight, discreet, and non-invasive solution.