【作者】 张辉；

【导师】 张宗华；

【作者基本信息】 河北工业大学 ， 仪器科学与技术， 2020， 硕士

【摘要】 准确实时的室内定位技术具有广泛的应用需求,并随着相关技术的进步成为一个研究热点。目前,可穿戴室内定位在儿童与老人护理、人体运动形态分析、康复医学、机器人导航等方面得到了广泛关注。在众多可穿戴室内定位技术中,超宽带(UltraWide Band,UWB)定位技术与惯性测量单元(Inertial Measurement Unit,IMU)定位技术是目前广泛应用的主要方法。然而,UWB定位易受信号稳定性及节点基站间遮挡影响,惯性测量由于无法避免误差累积而造成信号漂移,限制了二者定位精度的进一步提高。论文对将超宽带技术与惯性测量技术的集成方法进行深入研究,探索通过两种测量结果的迭代补偿,充分发挥了超宽带系统的定位结果长期稳定性和较高精度与惯性测量系统单步精度高并可计算速度方向等关键参数的优势。设计了一个轻量级、可穿戴、电池供电的低成本室内定位系统解决方案,并提出了相应的测量数据融合方法。在提高定位精度的同时可以获得传感器安装人体部位的姿态数据以便满足物联网应用中进一步数据分析的需求。论文的主要研究内容包括:(1)设计了利用低成本元器件构建的低功耗、小型化的可穿戴无线传感器硬件系统,以STM32单片机为主控模块,并分别集成了超宽带模块DWM1000,惯性测量单元MPU9250和蓝牙模块JDY-32。(2)针对超宽带系统中基站与标签之间由于时钟偏差导致测距误差增大的问题,应用双边双向测距方法来降低时钟偏差影响,提高测距精度。并将质心定位思想引入到三边定位中,弥补单一三边定位方法精度不高的缺陷。(3)在惯性测量系统中使用互补滤波器计算传感器的旋转姿态,并通过四元数实现载体坐标系到导航坐标系的转换,利用积分的方法获得连续的位置估计。针对超宽带系统与惯性测量系统定位结果的互补特性,应用改进的卡尔曼滤波算法实现定位数据的融合。对所设计传感器系统和采用计算方法进行了实验验证。实验结果表明,基于UWB/IMU的组合定位系统,通过运动姿态估计减小了UWB单步误差,通过UWB所测量长时间稳定性补偿了惯性测量误差的累积。所设计方法相比于单一定位技术在定位精度与稳定性方面有显著提高。更多还原

【Abstract】 Accurate and real-time indoor positioning technology has a wide range of application requirements,and with the progress of related technology has become a research hotspot.At present,wearable indoor positioning has received wide attention in the areas of child and elderly care,human movement morphology analysis,rehabilitation medicine,robot navigation,and so on.Among many wearable indoor positioning technologies,Ultra-Wide Band(UWB)positioning technology and Inertial Measurement Unit(IMU)positioning technology are the main methods widely used at present.However,UWB positioning is vulnerable to signal stability and occlusion between nodes and base stations.IMU positioning cannot avoid signal drift caused by error accumulation,which limits the further improvement of positioning accuracy of both.In this dissertation,the integration method of UWB technology and IMU technology is studied in depth,and the iteration compensation of the two measurement results is explored to make full use of the long-term stability of UWB positioning results and the advantages of high accuracy and single-step accuracy of the IMU System,as well as the calculation of speed direction and other key parameters.A lightweight,wearable,battery-powered,low-cost indoor positioning system solution was designed,and the corresponding measurement data fusion method was proposed.At the same time,the positioning accuracy can be improved,and the posture data of the human body part installed by the sensor can be obtained to meet the requirements of further data analysis in the application of the Internet of Things.The main research contents of this dissertation include:(1)Design a wearable wireless sensor hardware system with low power consumption and small size,which is constructed by low cost components,taking STM32 single-chip computer as the main control module,and integrates the ultra-wideband module DWM1000,the inertial measurement unit MPU9250 and the Bluetooth module JDY-32,respectively.(2)In order to reduce the influence of clock bias and improve the ranging accuracy,a two-sided bidirectional ranging method is applied to reduce the error caused by clock bias between base station and label in UWB system.The idea of centroid positioning is introduced into the three-sided positioning,which makes up for the defect of low accuracy of single three-sided positioning method.(3)In the inertial measurement system,the complementary filter is used to calculate the rotation attitude of the sensor,and the quaternion is used to convert the carrier coordinate system to the navigation coordinate system,and the continuous position estimation is obtained by the integral method.For the complementary characteristics of positioning results between UWB and IMU,an improved Kalman filter algorithm is applied to achieve the fusion of positioning data.The designed sensor system and the calculation method are verified experimentally.The experimental results show that the integrated positioning system based on UWB/IMU reduces the UWB single-step error by motion posture estimation and compensates the accumulation of inertial measurement error by the long-time stability measured by UWB.Compared with single positioning technology,the design method improves positioning accuracy and stability significantly.更多还原