High-Performance Fasciated Yarn Artificial Muscles Prepared by Hierarchical Structuring and Sheath–Core Coupling for Versatile Textile Actuators

Abstract

High-performance yarn artificial muscles are highly desirable as miniature actuators, sensors, energy harvesters, and soft robotics. However, achieving a yarn artificial muscle that covers all the properties of excellent actuation performance, mechanical robustness, structural stability, and high scalability by a low-cost strategy is still a great challenge. Herein, a bio-inspired fasciated yarn structure is first reported for creating robust high-performance yarn artificial muscles. Unlike conventional strategies that leverage costly materials or complex processing, the developed yarn artificial muscles are constructed by hierarchically helical and sheath-core assembly design of cost-effective common fibers, such as viscose and polyester. The hierarchically helical sheath structure pushes the theoretical limit of the inserted twist in yarns and endows the yarn muscles with large stroke (5815° cm⁻¹) and high work capacity (23.5 J kg⁻¹). Due to the rapid water transfer and efficient energy conversion of inter-sheath–core coupling, the as-prepared yarn muscles possess fast response, high rotation accelerated speed, and low recovery hysteresis. Moreover, the inactive core yarn serves as support for internal tethering and load-bearing, enabling these yarn muscles to maintain a self-stable structure, robust life cycle and mechanics. We show that the yarn muscle fabricated in this method is readily available and highly scalable for achieving high-dimensional actuation deformations, which considerably broadens the application scenarios of artificial muscles.

Graphic abstract

The hierarchically helical and sheath-core structures are embraced to create high-performanceartificial muscles with a large stroke, a fast response, a high work capacity, a self-supportingmorphology and robust mechanical properties at a low-cost strategy, which boosts thescalable production and practical applications of artificial muscles and is expected to providenew opportunities in the development of miniature actuators, smart textiles and soft robotics.

Funding

National Natural Science Foundation of China(11802104)