基于PVDF的柔性介电压力传感器的研究

柔性压力传感器因其柔性、贴合皮肤可穿戴以及可任意变形等特点，在可穿戴设备、人机交互和医疗健康检测等重要领域中，受到越来越多的关注和研究。其中电容式柔性压力传感器因灵敏度高和易阵列化等特点被广泛使用，常用作分布式压力测量。本文从电容压力传感器的介电层结构入手，建立传感器灵敏度等性能与微结构空间复杂度关系模型，研究影响电容传感器性能的物理学效应与机制。本论文设计优化基于微圆柱阵列化的介电层结构，选用杨氏模量较小的聚二甲基硅氧烷（PDMS）作为基底材料同时掺杂介电材料聚偏氟乙烯（PVDF）来提高压力传感器的灵敏度。制备的介电层通过等离子处理键合，在微结构层生成牢固的化学键，增强结构的稳定性和整个传感器的一致性，有利于提高多通道阵列电容位点的性能统一。通过激光切割制备可图案化的掩模版，喷涂银纳米线作为电极。选择光刻制备微结构模具，旋涂制备介电层薄膜。对制备的柔性压力传感器进行了性能分析，在低压强（<1kPa）下灵敏度约为0.35kPa^-1，36ms的快速响应时间，通过2000次重复性测试，具有良好的耐久度与稳定性，柔韧性较好，弧面不影响性能。搭建电容阵列采集软硬件系统，使用数字电容转换芯片PCap01AD采集，将其接入自研设计的电容采集电路，能较好的实现多通道的电容阵列测量，检测范围广，采集速度达到700Hz。通过单片机处理蓝牙发送数据与电脑上位机通信，实现显示与存储功能。达到了将采集系统轻便小型化的目的，能应用到人体健康检测、电子皮肤方面以及更多复杂的场景中。

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