Functional Fibers and Fabrics for Soft Robotics, Wearables, and Human–Robot Interface

Abstract

Fiber that has been known for thousands of years for textile engineering, is a kind of thin 1D material with large length-diameter ratio and softness. Fiber can be further processed into 1D or 3D yarns and 2D or 3D fabrics and can be subjected to wellestablished textile manufacturing techniques, such as dyeing, twisting, sewing, knitting, weaving, braiding, etc. [1] As commercially available material, fabric has been widely used for clothing, bedding, or furniture. Such wide-adoption demonstrates fabrics/textiles to be important and adaptable as daily useable material due to their merits of protection, breathability, comfort, and durability. [2] In recent years, novel smart responsive functions are desirable to be implemented on fibers and fabrics for seamless integrations of actuators, sensors, power sources, etc., to realize the robotic fibers/fabric-based manipulators and human-robot interfaces. These emerging responsive fibers/ fabrics are desirable to offer programmable functions, actuations, perception and capable of building an intuitive and dynamic collaborative scenarios with human, promising in enabling applications such as remote operation, human motion assistance, human perception, health monitoring and biomedical detection and therapy. [3][4][5] It is an attractive concept that the future human-robot interfaces could be embodied in familiar forms for humans such as textiles or clothes. Compared with the polymeric and elastomeric soft robotics, [6][7][8][9] fibers and fabrics are advantageous in applications of soft robotics and wearables for human. The devices could be programmable to have accurate designs in configuration and high performance by traditional manufacturing processes of textile, applying twist to transform fibers into coils, yarns with hierarchical structures, which could be further fabricated into fabrics or textiles by sewing, weaving, knitting, etc., techniques (Figure 1), guaranteeing good wearability, skin affinity, washability, and durability, which are intriguing and necessary for friendly robotics interactions with human.Soft robotics include three main components of actuators, sensors, and control modules with power sources. [10,11] Of which, actuators, sensors and power sources all could be designed in the form of fibers or fabrics, rendering facile assembly, and integration by interlocking. [12] Common actuations can be Soft robotics inspired by the movement of living organisms, with excellent adaptability and accuracy for accomplishing tasks, are highly desirable for efficient operations and safe interactions with human. With the emerging wearable electronics, higher tactility and skin affinity are pursued for safe and user-friendly human-robot interactions. Fabrics interlocked by fibers perform traditional static functions such as warming, protection, and fashion. Recently, dynamic fibers and fabrics are favorable to deliver active stimulus responses such as sensing and actuating abilities for soft-robots and wearables. First, the responsive mechanisms of fiber/fabric actu...

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