基于永磁定位技术的三维腿部运动检测系统设计  

Design of a Three-Dimensional Leg Motion Detection System Based on Permanent Magnet Positioning Technology

作　　者：张可[1] 汤福南[1] 李修寒 吴小玲[1] 

机构地区：[1]南京医科大学生物医学工程系,江苏南京210029

出　　处：《中国医疗设备》2017年第9期33-39,共7页China Medical Devices

基　　金：江苏省2015年度普通高校研究生科研创新计划项目(KYLX15_0938)

摘　　要：目的设计一种基于永磁定位技术的三维腿部运动检测系统,实现对腿部运动的实时显示。方法首先,在腿部关节点佩戴3轴磁传感器,小磁体佩戴在与其连杆的肢体上,两者距离约6 cm。磁传感器检测该小磁体的磁感应强度,并对采集到的信息进行多级放大、滤波处理,通过串口发送至上位机。其次,编写上位机程序。利用Labview软件处理接收到的电压信号,还原为磁感应强度信号,并通过PSO与LM算法结合进行磁源定位。最后,加载三维腿部骨骼模型,实现直观的三维实时显示。结果磁传感器检测范围实验显示,小磁体与磁传感器之间距离设置为6 cm时,既可满足磁偶极子模型,又对临近组传感器无影响。小磁体3轴定位平均误差在1 cm之内,整个系统完成一次完整的数据采集约耗时17.5 ms,基本满足实时性的要求。三维腿部运动检测实验显示,实验结果与被测者腿部姿态基本一致。结论基于永磁定位技术的三维腿部运动检测系统能够实现三维腿部运动检测功能,为步态检测及腿部康复训练提供了一种新方法。Objective To design a kind of three-dimensional leg motion detection system based on permanent magnet positioning technology to achieve real-time display of leg motion. Methods Firstly, the three-axis magnet sensors were placed on the leg joints, and the small magnets were placed on the limbs which were connected to the leg joints, while the distance between the sensor and magnet was about 6 cm. The sensors were used to detect the magnetic induction intensity. The signal was gradually exaggerated and fltering processed, and was sent via the serial port to PC. Secondly, the magnetic induction intensity of the signal was converted into a voltage signal by LabVIEW software, and the voltage signal was combined with LM algorithm and PSO algorithm and was used for magnet source localization. Results The experiment for detection range of Magnetic sensor showed that when the distance between the sensor and magnet was about 6 cm, it could be considered as a magnetic dipole model and had no effect on the near magnet group. When the magnets were positioned within the average error of 1 cm, the entire system spent about 17.5 ms on fnishing a complete data collection, which could basically meet the real requirements. The experiment for three-dimensional leg motion showed that the result was consistent with the examinee leg stance. Conclusion The three-dimensional leg motion detection system based on permanent magnet leg positioning technology can achieve three-dimensional leg motion detection function, which provides a new method for detecting gait and leg rehabilitation training.

关 键 词：运动检测 永磁定位 三轴磁传感器 定位算法 

分 类 号：TH789[机械工程—仪器科学与技术]