基于碳基纤维网络的假肢手触觉感知机理及解耦方法研究

Tactile perception is an important method to acquire information from the environment for the next generation of the smart prosthesis that should support the man-machine interaction. However, the researches on tactile sensing to date have mainly focused on the development of sensing mechanisms, whereas fewer attentions are paid to the integrated performance. Hence, this project aims to research on the mechanism and decoupling method of tactile sensing on prosthesis hand based on carbon-based fiber arrays (CBFA). The proposal will utilize the self-sensing ability and high modulus rate properties of carbon fiber reinforced composites (CFRC) to fulfill the requirements of tactile sensing for detection of distributed mechanical stimulation on the prosthesis. Firstly, the piezoresistive property of the carbon fiber and carbon nanotube in the polymer matrix will be studied and then the decoupling method for distributed tactile information from CBFA will be developed. Finally, this research would fabricate tactile sensitive shells with the bionic surface, lightweight and high strength for prosthesis hand based on the designability and high strength rate of braiding CFRC. We hope that, through this work, the mechanism of tactile sensing of CBFA in composites could be fully understood. Moreover, this research will not only archive a new effective method of tactile sensing for the smart prosthesis but also extend the application of braided composites to the bionic sensing area.

新一代智能假肢需要为人机交互提供必要的信息支持，而触觉感知是其获取环境信息的重要方式。但目前对触觉传感技术的研究主要集中在柔性与高密度等器件本身的特性上，而对器件在假肢表面上集成性能方面的考虑较少。为此，本项目面向分布式机械刺激触觉传感的共性需求，基于碳基纤维复合材料的自敏感特性与高比模量特性，提出开展具备触觉功能的仿生曲面壳体的感知机理与信息提取方法的研究。利用碳纤维在聚合物-碳纳米管混合基体中的压阻敏感能力，研究复合材料中碳纤维网络对触觉压力的分布式检测方法与压力分布信息的解耦方法。充分结合编织纤维复合材料的可设计性特点与高比强度优势，研究仿人手外形、重量轻、强度高的复杂曲面壳体的设计方法。为深入理解复合材料内碳基纤维网络的敏感特性提供理论基础，为以灵巧假肢手为代表的智能假肢装备提供一种整体、高效的提取分布式机械刺激信息的新方法，促进编织复合材料的设计制造优势在仿生传感领域的拓展应用。

人工假肢手从出现开始经过了不断的改进，从最早的以美观为主要目的的木制假肢，到后来的具备操作能力的机械假肢，最终向智能假肢这一方向发展。触觉传感器为智能假肢的人机交互提供必要的信息支持，是其获取环境信息的重要方式。针对现有的人工触觉传感阵列在假肢手上应用时存在的结构和功能之间的矛盾，本项目开展了碳基纤维复合材料的触觉感知机理与信息提取方法的研究。首先，提出了基于碳纤维-环氧树脂复合材料壳体的分布式压力检测方法，利用碳纤维复合材料的压阻效应，实现了对压力的分布和方向的实时检测；其次，研究了不同织物增强体结构对复合材料壳体的强度影响，建立了电阻变化与结构强度之前的对应关系；再次，从压电与压阻两个方面着手，一方面提出了基于碳纳米管-聚偏二氟乙烯压电复合材料的柔性触觉敏感单元结构，实现了动态三维接触力的检测，另一方面基于碳纳米管-聚氨脂微纳米纤维的压阻效应，设计了柔性敏感阵列，能够检测接触力在三维方向上的分布。项目的研究成果可以为智能假肢的轻量化自敏感壳体设计和基于壳体的柔性触觉传感提供理论支撑。