可穿戴生物电干电极关键技术研究

Currently, the biopotential recording electrode is a bottleneck of the development of the technology of the wearable biopotentials recoding because of its short time of usage，low comfort level, low capability of anti-interference. Therefore, a project of wearable dry electrode investigations based on MEMS was presented. The project mainly focuses on the theoretical research of biopotentials recording by dry electrodes. Finally, novel wearable dry electrodes will be developed by increasing conductivity of conductive polymer composites and optimizing structures of electrodes. The mechanism of recording biopotentials by dry electrodes will be investigated by building interfaces models of electrode-skin and the simulation and calculation. The methods of increasing the conductivity of conductive polymer composites will be investigated by changing the distribution of conductive particles in the polymer matrix. The structures of electrodes will be optimized based on two ways: increasing the anti-interference capacity of dry electrodes, and increasing the resistance of motion artifact. Finally, methods of performance valuation of dry electrodes will be improved by building a model of the electrode-skin. The aim of this project is development of wearable dry electrode with high signal to noise ratio and anti- interference ability. The results of this project will not only will help solving the problems shown in the wearable technology theoretically and technically, but also will provide a new solution for the biopotentials recording.

鉴于目前生物电电极使用时间短、抗干扰能力差、舒适度低等问题，其已成为制约可穿戴生物电记录技术发展的瓶颈。为此，本项目拟基于MEMS技术研究可穿戴生物电干电极技术，重点研究干电极记录生物电的机制；并通过提高复合导电聚合物的导电率和优化电极结构，研制出新型的可穿戴干电极。通过建立电极-皮肤接触模型和仿真计算，研究干电极记录生物电的机制；通过改变导电粒子在聚合物中的分布以提高复合导电聚合物的导电性能；从提高电极抗干扰性能和降低电极易受运动伪迹影响两方面研究，优化电极的结构；通过搭建电极-皮肤模拟平台，改进电极性能测试方法。本项目的目标研制出高信噪比、抗干扰能力强的可穿戴生物电干电极。本项目的研究成果，将不仅为可穿戴技术提供重要的理论依据和技术支持，而且为生物电记录问题提供新的解决思路。

生物电信号是人体生命活动过程中产生的电信号，包含着很多重要的信息。这些信息不仅可以用于健康监测、医疗康复等生物医学领域还可以用于脑机接口和人机交互等领域。随着生物电的用途不断的被开发，对于可穿戴式的记录生物电的需求日益增大。而传统湿电极（Ag/AgCl电极）无法满足现在对可穿戴式记录生物电的需求。因此研究干电极记录生物电的技术对实现可穿戴记录生物电十分必要。本项目中通过搭建模拟平台和等效电路模型研究了干电极记录生物电的机制，为干电极的设计提供了理论依据。通过本项目的执行，研制了2种柔性干电极：表面具有微金字塔结构的Pt/PDMS电极和基于二维材料的MXene的MXene/PI电极。实验表明Pt/PDMS电极比平面电极具有更小的接触阻抗，记录到的心电信号和湿电极一样精确； MXene/PI电极具有低的接触阻抗和高信噪比，可以精确的采集到心电，眼电和脑电信号，并且记录到的信号质量和Ag/AgCl电极一样好。这两种柔性干电极有希望用于可穿戴式的健康检测系统，脑机接口和人机交互。