纺织基柔性触觉传感器及可穿戴应用进展

Textile-based flexible tactile sensors and wearable applications

触觉传感器是智能可穿戴设备和人机交互领域的重要研究方向,引起了人们广泛的关注。传统刚性材料的触觉传感器普遍存在坚硬且不适合穿戴交互等瓶颈问题,限制了其在可穿戴领域的应用。纺织基柔性触觉传感器由于其高灵敏性、柔软性和可穿戴性成为触觉传感材料的首选。本文综述了几类纺织基柔性触觉传感器的原理和应用,包括电阻式、电容式、压电式和摩擦电式。结果表明:纺织基柔性触觉传感器由于其特殊的纺织结构,有优异的线性度、灵敏度、耐久性和稳定性。高灵敏性、耐久性和可穿戴性是纺织基柔性触觉传感器的优势和重要发展方向。

Tactile sensors are an important research direction in the field of smart wearable devices and human-computer interaction, which has attracted extensive attention. Tactile sensors of traditional rigid materials generally have bottlenecks such as being hard and not suitable for wearable interaction, which limits their application in the wearable field. Textile-based flexible tactile sensors have become the first choice for tactile sensing materials due to their high sensitivity, softness, and wearability.The textile-based flexible tactile sensor is a new development direction of flexible sensors for the following reasons. First, its special textile structure can be seamlessly connected with clothing to achieve the integration of design, wear and application. Second, sensors with different dimensions can be developed at different stages of textiles, and there are one-dimensional fiber and yarn sensors, two-dimensional fabric sensors and three-dimensional clothing textiles. The sensing application range in different dimensions is different. Compared with the low response and high sensitivity based on the fiber/yarn sensor, the fabric/textile sensor has a larger sensing area and a more ideal array design. More importantly, wearable devices that combine sensing with textiles have excellent sensing performance and comfort, and can be widely used in medical care, sports detection, leisure and entertainment and other fields.This paper reviews the principles and applications of several types of textile-based flexible tactile sensors, including resistive, capacitive, piezoelectric, and triboelectric ones. The results show that the textile-based flexible tactile sensor has excellent linearity, sensitivity, durability and stability due to its special textile structure. The textile-based flexible resistive tactile sensor has a simple structure and can achieve high performance and low cost. However, the energy consumption is high and the recovery rate is low. Future directions are to design materials in which resistance changes do not depend on the deformation of the conductive network between nanomaterials, or to create additional free-space pores so that the resistance changes are caused by the closure of pores in the material rather than by polymer chains in elastomers. The problem of textile-based flexible capacitive tactile sensors is how to improve the sensitivity. In order to achieve high sensitivity, dielectric materials can be designed by increasing the pores or increasing the dielectric constant. For future research directions, porous high dielectric constant materials or elastomers coated with conductive nanomaterials can be used as high dielectric constant composites. Textile-based flexible piezoelectric tactile sensors have high sensitivity and excellent dynamic response, making them the first choice for detecting dynamic pressure. In the future, we should develop new materials in the available piezoelectric materials for tactile sensing to enhance output power, realize high performance and reduce production costs. The main problem of textile-based flexible triboelectric tactile sensors is to develop stable and high-performance TENGs, and we should study excellent polar electrodes and ensure the stability of sensing performance.In conclusion, high sensitivity, durability and wearability are the advantages and important development directions of textile-based flexible tactile sensors. The textile-based flexible tactile sensor is one of the important research focuses in the future, and there are also several directions that need to be broken through. First, it is still a difficult problem to obtain a flexible sensor that integrates high sensitivity, wide range, fast response, washability and wearability. Analyzing and solving these key problems plays an important role in promoting the development of the industry. Second, on the premise of ensuring softness and wearability, it is necessary to ensure the comfort of wearing, and combine the advantages of functional textile substrate such as breathability, sweat prevention, and anti-bacterial effects. Third, the cost efficiency should be considered for the applied sensor. The low-cost flexible sensor that can be manufactured in large area and has high performance is the focus of future development. Fourth, the sensing performance should be combined with the life function. The development of flexible tactile sensors in the intelligent wearable field should be combined with human-computer interaction. In the direction of medical treatment, sports and entertainment, it should be suitable for people’s life. It should be combined with the current cutting-edge technology to develop practical applications to improve people’s living standards. Finally, the solution of these problems requires the joint research of cross-disciplines, including materials science, medicine, textile science, computer technology, software application development and communication technology. Such research has great potential and important significance.