基于加速度传感器的睡眠体位监测方法的研究

摘要

目的:睡眠质量是保证身体健康的重要因素,目前常用的评价方法有主观评价法和客观评价法两种,各有利弊.持续监测睡眠过程中身体位置的变化是客观评价睡眠质量的方法之一.为了能够低成本、大量、准确的采集睡眠状态信息,介绍一种基于加速度传感器的睡眠体位检测的方法.方法:加速度传感器能准确感知人体体位变化,具有体积小精度高的特点.通过佩戴在小腹位置的以IAP12LE5A62AD单片机和MMA7361加速度传感器为核心的微型体位状态采集设备连续采集睡眠期间的身体位置状态,然后通过上位机软件对体位信号的突变、渐变、状态间相似度进行分析,从中分离出相关体位信息.结果:对静态体位信号和身体位置的快速变化的识别率较高,查全率达到98.9％以上,查准率超过93％,对于缓慢变化的身体状态的识别率略低,查全率达到85％以上,查准率达到96％.结论:该方法结构简单、成本低,对睡眠影响很小,能够比较准确的反映睡眠过程中体位状态,可以用来评价睡眠质量,适用于对大量患者长时间的睡眠监测.%Sleep quality is an essential factor for human health. Presently the evaluation methods widely used are subjective evaluation method and objective evaluation method, and each has its advantages and disadvantages. Continuous acquisition of body posture is one of the ways in objective evaluation of quality of sleep in patients. In order to gathering body postures information in sleep with low-cost, widely and accurately, the paper introduces a method for monitoring body posture in sleep based on an accelerometer. Methods: Acceleration sensor has an ability of accurate prediction of the change of body posture, which is characterized by small volume and precise accuracy. By a miniature device which using microcontroller of IAP12LE5-A62AD and accelerometer of MMA7361 continues recording body postures information in sleep worn on belly, and then uses computer software analyzing signals of gradual and sudden change, postural similarity, and so relevant information of body postures in sleep are extracted. Results: The result shows that the method has high recognition rate to signals of static body postures and rapidly changes in body posture, 98.9% recall with 93% precision have been achieved. To the signals of gradual change in body posture, the recognizing rate is relatively low, 85% recall with 96% precision have been achieved. Conclusions: This method nearly has no effect on sleep as well as maintains advantages of low cost, convenient operation and brief recording process. The method can accurately reflect the main changes of body in sleep. It can evaluate sleep quality better and be suitable for patient to do a long-term sleep monitoring.