【作者】 江南；

【导师】 刘宏；

【作者基本信息】 东南大学 ， 生物医学工程， 2025， 硕士

【摘要】 心血管疾病是全球首要死因,长期、连续的血压监测对疾病的早期预警和个性化管理具有重要意义。传统袖带式测量仅能提供单次静态血压数据,无法捕捉血压波动规律,而有创监测因侵入性限制难以普及。近年来,基于脉搏波传导时间（PTT）的无创可穿戴设备因其舒适性和动态监测能力成为研究热点,但现有系统通常需要心电和光电容积图等多传感器协同工作,由于不同传感器的信号采集机制和封装工艺差异显著,导致设备体积臃肿且信号同步困难,制约了其在日常健康监测中的实际应用。突破多模态传感器的集成瓶颈、开发高精度算法,是实现可穿戴血压监测技术临床转化的关键挑战。本研究创新性地提出了一种基于PTT技术的高度集成的可穿戴双模传感器用于血压连续监测。该传感器将液态金属电路与离子凝胶基质复合,实现了推导PTT所需脉搏波和心电信号的一体化同步监测。其中,液态金属为镓铟共晶合金,所构建的蛇形电路作为压力传感单元(灵敏系数为0.074 k Pa^-1),用于采集脉搏波信号。离子凝胶具有良好可拉伸性（断裂长度为300%）、粘附性(粘附强度为80 N m^-1)和离子导电特性(10⁵ Hz下的导电率为0.26 S m^-1),能够与皮肤形成紧密且稳定的界面接触,实现高质量心电信号的采集（信噪比大于50 d B）。该双模传感器与印刷电路板集成,通过蓝牙无线传输脉搏波和心电信号至移动终端,并基于PTT算法建立血压预测模型,实现了收缩压和舒张压的连续监测。基于商用血压测量结果,本双模传感器在被试静息状态下收缩压和舒张压的测量平均绝对百分比误差（MAPE）分别为3.98%和5.32%;被试运动状态下测量的收缩压和舒张压的MAPE分别为2.51%和1.30%。此外,无论是静息还是运动状态的所测血压的平均误差（ME）和标准差（SD）达到美国医疗器械促进协会标准（ME≤5 mm Hg,SD≤8 mm Hg）,达到临床诊断的精度要求。综上所述,本文设计的双模态可穿戴传感器实现了脉搏和心电的信号同步采集,并能准确预测血压。这种一体化设计不仅解决了传统多传感器测量中存在的同步性差、佩戴不便等问题,还为可穿戴健康监测设备的微型化和集成化提供了新的技术路径。更多还原

【Abstract】 Cardiovascular disease is the leading cause of death globally,making long-term,continuous blood pressure monitoring crucial for early disease detection and personalized management.Traditional cuff-based measurements only provide single static readings,failing to capture dynamic fluctuations,while invasive monitoring is impractical for widespread use due to its intrusive nature.In recent years,non-invasive wearable devices based on pulse transit time（PTT）have gained research attention for their comfort and dynamic monitoring capabilities.However,current systems typically require multiple sensors,such as electrocardiogram（ECG）and photoplethysmography,to work in tandem.Significant differences in signal acquisition mechanisms and packaging technologies among these sensors result in bulky designs and signal synchronization challenges,limiting their real-world application in daily health monitoring.Overcoming the integration barriers of multi-modal sensors and developing high-precision algorithms remain key challenges in advancing wearable blood pressure monitoring toward clinical adoption.The sensor integrates liquid metal circuits with an ionogel matrix,enabling synchronous and integrated monitoring of both pulse wave and electrocardiogram（ECG）signals required for PTT derivation.Specifically,the eutectic gallium-indium alloy forms serpentine-shaped stretchable circuits that function as pressure-sensing units(with a sensitivity coefficient of 0.074 kPa^-1)for pulse wave signal acquisition.The ionogel demonstrates excellent mechanical and electrical properties,including remarkable stretchability（300%fracture strain）,strong adhesion(80 N m^-1adhesive strength),and superior ionic conductivity(0.26 S m^-1at 10⁵ Hz).These characteristics ensure conformal and stable skin-device interface contact,thereby facilitating high-quality ECG signal acquisition with a signal-to-noise ratio（>50 d B）.The dual-mode sensor is incorporated with a printed circuit board for wireless Bluetooth transmission of both pulse wave and ECG signals to mobile terminals.A PTT-based algorithm is employed to establish a blood pressure prediction model,achieving continuous monitoring of systolic and diastolic blood pressure.Benchmarked against commercial blood pressure measurement devices,the dual-mode sensor showed mean absolute percentage errors（MAPE）of 3.98%for systolic blood pressure（SBP）and 5.32%for diastolic blood pressure（DBP）at rest,and MAPEs of 2.51%（SBP）and 1.30%（DBP）during motion.Furthermore,both resting and motion measurements met the Association for the Advancement of Medical Instrumentation（AAMI）standards with mean error（ME）≤5 mm Hg and standard deviation（SD）≤8 mm Hg,satisfying clinical accuracy requirements.In summary,the dual-mode wearable sensor designed in this study achieves dual-signal acquisition of pulse and ECG and accurately predicts blood pressure.This integrated design not only addresses issues such as poor synchronization and inconvenience in traditional multi-device measurements but also provides a new technological pathway for the miniaturization and integration of wearable health monitoring devices.更多还原