基于MEMS惯性传感器的跌倒检测及其防护系统

发布时间：2018-04-22 07:12

本文选题：跌倒检测 + MEMS惯性传感器　；参考：《南昌航空大学》2017年硕士论文

【摘要】：针对我国老龄化社会未富先老的特点,作为社会重要构成人群老年人的健康也将对国家产生巨大影响,而跌倒会严重威胁老年人的身体健康。老年人一旦发生跌倒,将直接危害到生命安全以及加重家庭和社会的负担。因此,研究开发人体跌倒预警及其防护设备对于减少由跌倒带来的损害具有重要意义。系统采用STM32F405RG为主控芯片,MPU9150九轴传感器为MEMS惯性传感器,SIM900A作为GSM/GPRS通讯模块,UM220作为GPS/BD定位模块,通过这几个模块的组合构成了一个跌倒检测下位机节点。我们通过MEMS惯性传感器来采集人体运动数据,结合由多次人体跌倒实验得出的跌倒时加速度、姿态角等特征,经过充分分析比对后得出合理的姿态角和合加速度的阈值。从而系统能够在跌倒发生后人体着地前发出跌倒预警,MCU把GPS模块采集到的跌倒时的地理位置信息提取后加入到短信格式中,在跌倒时通过GSM/GPRS模块发送出去,告知其监护人已经检测到跌倒的发生。此外,在PC端还有能够对下位机传感器传来的运动数据进行显示、分析、处理的上位机人体惯性数据采集监测系统,该监测系统能够实时显示9轴数据的波形曲线,同时具有运动数据的存储和回放功能。在完成了跌倒检测节点的设计后,把节点接上控制舵机部分驱动一个髋关节安全气囊,组成跌到检测及其防护系统。当系统的跌倒检测算法检测到跌倒即将发生时,MCU给舵机发送信号驱动舵机上的刺针刺破气瓶,使得系在人体腰间的气囊快速充气,在人体着地时保护人体髋关节,减少跌倒时地面对人体的冲击。跌倒检测装置的核心在于摔倒的检测算法,摔倒检测算法是需要以大量跌倒实验为基础,通过人体惯性传感器采集跌倒实验中的跌倒数据特征,再对加速度计、陀螺仪原始数据进行原始数据处理,然后使用数字滤波融合算法来举行人体姿态解算。最后,将姿态解算得出的人体合加速度、姿态角数据与分析得出跌倒的合加速度、姿态角的阈值进行对比,从而实现跌倒行为的检测。我们把系统佩戴在腰部进行模拟摔倒实验,在摔倒过程中系统正常工作,摔倒检测的准确度达到98%以上,并且气囊能够在跌倒前充分打开,在跌倒时能够保护人体。
[Abstract]:In view of the characteristics of aging society in our country, as an important social group, the health of the elderly will also have a great impact on the country, and falling down will seriously threaten the health of the elderly. Once the elderly fall down, it will directly endanger the safety of life and increase the burden on families and society. Therefore, the research and development of human fall warning and its protective equipment is of great significance to reduce the damage caused by fall. The system uses STM32F405RG as main control chip MPU9150 nine-axis sensor as MEMS inertial sensor and SIM900A as GSM/GPRS communication module and UM220 as GPS/BD positioning module. Through the combination of these modules, a fall detection node is constructed. The MEMS inertial sensor is used to collect human motion data. Combining with the characteristics of fall acceleration and attitude angle obtained from multiple human fall experiments, a reasonable threshold of attitude angle and acceleration is obtained after full analysis and comparison. Therefore, the system can send out the fall warning system before the human body lands on the ground after the fall, and add the geographic position information of the fall collected by the GPS module to the short message format, and send it out through the GSM/GPRS module when the fall occurs. Inform his guardian that a fall has been detected. In addition, there is an upper computer inertial data acquisition and monitoring system on PC, which can display, analyze and process the motion data from the sensor of the lower computer. The monitoring system can display the waveform curve of 9-axis data in real time. At the same time, it has the function of storage and playback of moving data. After the design of the tumble detection node is completed, the joint is connected to the control steering gear to drive a hip joint airbag to form a detection and protection system. When the fall detection algorithm of the system detects that the fall is about to happen, MCU sends a signal to the steering gear to drive the needle on the steering gear to puncture the cylinder, so that the air bag tied to the waist of the human body is inflated quickly, and the human hip joint is protected when the human body lands on the ground. Reduce the impact of a fall on the human body. The core of the fall detection device is the fall detection algorithm. The fall detection algorithm needs to be based on a large number of fall experiments, through the human body inertial sensor to collect the fall data characteristics in the fall experiment, and then to the accelerometer, The original data of gyroscope are processed and the human pose is solved by digital filtering fusion algorithm. Finally, the human body acceleration and attitude angle data obtained by attitude solution are compared with the fall acceleration and attitude angle threshold, so as to realize the fall behavior detection. We wear the system in the waist to simulate the fall experiment, the system works normally during the fall, the accuracy of the fall detection is over 98%, and the air bag can be fully opened before the fall, and can protect the human body during the fall.
【学位授予单位】：南昌航空大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：R318.6;TP212

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