Advances in shape memory alloy textiles for wearable applications: A critical review

The advancement of wearable technology has driven research into shape memory alloy (SMA) textiles for diverse applications, enhancing comfort, functionality, and adaptability. This review systematically analyzes 30 studies published up to November 2024, examining SMA textile structures, actuation mechanisms, applications, and user evaluations. SMA textiles are categorized into knitted, woven, and knot structures, each with distinct advantages and limitations. Contraction actuation is widely studied, particularly in rehabilitation and compression wear, while bending actuation is gaining attention for localized motion assistance. However, challenges related to energy consumption, durability, and response time continue to hinder practical implementation. Standardized usability assessments are lacking, as most studies rely on laboratory-based testing rather than real-world evaluations. Hybrid actuation mechanisms that integrate contraction and bending remain underexplored, limiting their multifunctional potential. Future research should prioritize energy-efficient activation strategies, improved material durability, and standardized testing protocols to enhance real-world applicability. This review provides a critical analysis of SMA textile technologies, highlighting key research gaps and future directions to improve functionality, wearability, and commercialization potential.