基于离子弛豫时间响应的多模态传感器与热源识别研究

电子皮肤作为一种新兴的模仿人体皮肤感知功能的柔性电子器件，可为机器人和假肢等设备提供温觉和触觉反馈，使其更加真实地与环境和物体进行交互。然而，目前存在的温觉电子皮肤功能相对单一，难以满足复杂应用场景的需求，尤其在热源识别方面仍存在巨大挑战。本论文基于离
子弛豫时间响应机制，制备了可解耦温度、压力和接近三种刺激的多模态传感器，并创新性地解决了温觉仿真中的热源识别难题。 

本文系统研究了聚丙烯酸基（PAA-𝑥MX/𝑦H₂O）和聚丙烯酸丁酯基（PBA-𝑥LiX）离子凝胶的离子弛豫响应特性与多模态传感性能。研究发现，弛豫频率范围、温度灵敏度等离子弛豫响应特性与离子凝胶的成分密切相关，适合选用低浓度和大尺寸的活性离子及低的水含量。本论文制备了高灵敏度的 PAA-1 wt.%AlCl₃ /20 wt.%H₂O 离子凝胶，其负温度系数高达11%/°C，高于文献值；以及宽工作温度窗口（-20~146 °C）的 PBA-2 wt.%LiPFSI 无溶剂离子凝胶，负温度系数高达 10.3%/°C，测温精度优于0.05 °C，在 300 次升降温循环中误差低于 0.1 °C，同时实现 400 kPa以内压力刺激的无串扰传感，压力检测限低至 0.5 kPa。 

本文基于 PBA-LiPFSI 多模态传感器对热和力刺激的灵敏响应，开展了多模态传感系统对于热源识别的研究。传感器利用接近感应分辨出热传导，利用风压感知分辨出热对流，最终实现热传导、热对流和热辐射三种传热方式的热源识别，能够灵敏地在热传导刺激下检测 1~10 cm内的接近度，在热对流刺激下检测 2.5~22 m/s内的风速，并在热辐射刺激下感知0.5~2 kW/m²内的光照强度。本论文对于热源识别的研究，拓展了热传感的研究范畴。

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