离子电容和霍尔效应协同的柔性多维力传感器

文章采用聚乙烯醇和纳米纤维素纤维作为基体, 以氯化钙和硼酸钠作为离子源, 并结合倒模工艺, 制备了一种基于离子介电层和皮革表层微结构的高灵敏度电容式压力传感单元, 该传感单元在 $ 0 \sim 500 \, kPa $ 压力传感范围下, 灵敏度高达 $ 24.6 \, kPa^{-1} $, 响应时间为 $ 35 \, ms $, 循环稳定性超过 1 000 次; 同时设计一种基于三轴霍尔芯片的切向力传感单元, 该传感单元切向力在 $ \pm 20 \, N $ 范围内, 检测的磁感应强度变化率约为 $ 1.362 \times 10^{-2} \, T/N $. 将所研制的压力传感单元与切向力传感单元集成得到一种机器人多维力传感器, 并将其应用于电力巡检机器人巡检时的插拔作业. 结果表明, 基于多维力传感器的信号特征, 该机器人可以实时监测并判断插拔作业中如滑移、正常、卡壳等典型工作状态, 有效提升了机器人作业过程的全程感知能力及安全程度.

A high-sensitivity capacitive pressure sensing unit was fabricated using polyvinyl alcohol (PVA) and nanocellulose fibers as the matrix and calcium chloride and sodium borate as ionic sources, combined with an inverse molding process. This unit, featuring an ionic dielectric layer with leather-inspired surface microstructure, demonstrates a maximum sensitivity of 24.6 kPa $ ^{-1} $ within 0-500 kPa, a response time of 35 ms, and cyclic stability exceeding 1 000 cycles. Meanwhile, a tangential force sensing unit based on a triaxial Hall chip was designed, showing a magnetic induction intensity variation rate of approximately 1.362×10 $ ^{-2} $ T/N over a tangential force range of ±20 N. By integrating the developed pressure and tangential force sensing units, a robotic multi-dimensional force sensor was constructed and applied to plugging/unplugging tasks of electric power inspection robots. Experimental results confirm that, based on multi-dimensional force sensor signal characteristics, the robot can monitor and discriminate typical states, such as slippage, normal operation, and jamming, in real time during plugging/unplugging operations, significantly enhancing the robot's operational perception and safety.