基于柔性触觉传感器的足底压力分布研究

RESEARCH ON PLANTAR PRESSURE DISTRIBUTION BASED ON FLEXIBLE TACTILE SENSOR

谢珂玮

11849054

硕士

光电信息科学与工程

郭传飞

2020-05-28

2020-07-01

哈尔滨工业大学

深圳

近年来柔性电子学快速发展，已经成为未来生物医疗领域的重要革新手段，柔性触觉传感器对可穿戴式的医疗设备产生了颠覆性的影响。足底压力分布能够反映足部受伤或病变，被广泛应用于健康监测和医疗诊断当中。但往往受限于检测设备不便携、价格昂贵的缺点而没有被广泛应用。针对这一问题，相关人员提出使用柔性触觉传感器检测足底压力分布。柔性触觉传感器具有柔软、可拉伸、更好的贴附性等优点，但目前的大多数性能优良的器件加工成本高、检测范围小、容易破损导致无法发挥其应用优势。为此，本论文通过使用导电织物和微孔滤膜制作了电容式柔性触觉传感器并进一步制作了足底压力分布测量鞋垫解决上述问题。本文使用离子液体 1-丁基-3-甲基咪唑六氟磷酸盐活化微孔滤膜得到活性介电层与织物电极组装后形成三明治结构的离子型电容式柔性触觉传感器。通过调控离子液体负载量对器件进行优化，该器件在 0-25 kPa 时器件的灵敏度为0.14 kPa -1 ，在 25-300 kPa 时降至 0.012 kPa -1 。器件的响应时间小于 100 ms，能够对 20 Pa 以上的压力产生反馈，能承受 3000 次循环加载而保持稳定。此外，该器件具有制备工艺简单、原料易得，成本低的特点，解决了在实际应用中价格昂贵、生产效率低的不足。设计了六分区的足底压力分区方法，并依此在单足面积内安装了 25 个上述传感器制作了智能鞋垫。实验中采集了不同姿态下的足底压力分布情况，对静态站立时足底压力分布及压力中心点识别可以作为生物特征识别信号，验证了前足与足跟为足底压力的主要承重区域占总压力的 91%；通过对步态过程中足底压力变化的检测标定了步态过程，运用智能鞋垫对步态分析的结果在步态训练，机器外骨骼操控中有广阔的应用价值；此外还检测了两种不同康复训练模式下的足底压力分布，分析了在由站姿到坐姿再到站姿以及向左转身和向右转身的动作中足底压力分布的变化。综上所述，基于柔性触觉传感器的智能鞋垫的研究及其应用于足底压力分布测量的研究具有重要意义和实用价值。

In recent years, the rapid development of flexible electronics has become an important innovation in the future biomedical field. flexible tactile sensors have a disruptive effect on wearable medical devices. Plantar pressure distribution can reflect foot injuries or lesions, and was widely used in health monitoring and medical diagnosis. However, it was often limited by the shortcomings of detection equipment that are not portable and expensive, and therefore it was not widely used. To overcome the above problems, the application of a flexible tactile sensor on detecting some pressure distribution of the plantar was proposed. Flexible tactile sensors have the advantages, like softness, stretchable, and better adhesion. However, most of the current sensors with excellent performance cannot be readily applied because of the high processing cost, small detection range, and fragility. To this end, this paper used conductive fabrics and microporous membranes to make capacitive flexible tactile sensors and further made smart insoles to solve the above problems.In this paper, the ionic liquid 1-butyl-3-methylimidazole hexafluorophosphate is used to activate the microporous membrane to obtain an active dielectric layer. After assembling with the fabric electrode, an ionic capacitive flexible tactile sensor composed of a sandwich structure is formed. The device was optimized by adjusting the loading of ionic liquid. The sensitivity of the device is 0.14 kPa -1 at 0-25 kPa, and decreases to 0.012 kPa -1 at 25-300 kPa. The response time of the device is less than 100 ms, it can generate feedback for pressures above 20 Pa, and can withstand 3000 cycles of loading to maintain stability. In addition, the device has the characteristics of simple preparation process, easy availability of raw materials and low cost, which solves the problems of high price and low production efficiency in practical applications. Plantar pressure distribution was divided into six zones, and installed 25 of the above sensors in a single foot area to make a smart insole. In the experiment, the plantar pressure distribution in different postures was collected, and the plantar pressure distribution and pressure center point during static standing can be used as biometric identification signals. It was verified that forefoot and heel are the main load-bearing areas of plantar pressure, accounting for 91% of the total pressure. The gait process was calibrated through the detection of the changes in plantar pressure during the gait process. The results of gait analysis using smart insoles have broad application value in gait training and machine exoskeleton manipulation. In addition, the plantar pressure distribution under two different rehabilitations training modes were detected, and the changes in the plantar pressure distribution during the movements from standing position to sitting position to standing position and turning left and right were analyzed. In summary, the research on the intelligent insole based on the flexible tactile sensor and its application to the measurement of the pressure distribution of the plantar are of great significance and practical value.

柔性触觉传感器 离子液体 足底压力 步态 康复训练

flexible tactile sensors ionic liquid plantar pressure gait rehabilitation training

中文

联合培养

南方科技大学

谢珂玮. 基于柔性触觉传感器的足底压力分布研究[D]. 深圳. 哈尔滨工业大学,2020.