超宽带矢量测距与惯性传感组合的精准步长计算算法

Accurate step length calculation algorithm combining ultra-wide bandvector ranging and inertial sensing

为适应复杂环境下变步长精准测量要求,提出一种基于超宽带(ultra wide band,UWB)矢量测距和惯性传感组合的精准步长计算算法;针对基于惯性传感组合的步长测算精度受佩戴方式和系统运行时间影响以致无法实现行人步长精准测量和长航时精度保持的问题,提出一种结合足间模型与零速检测联合步长算法。根据行人行走时足部轨迹模型构造足间步长模型,得到准确的步长计算公式;根据足部惯性传感器运动特征进行零速检测并触发UWB测距,结合陀螺解算角度和足间模型公式计算得到步长。实验表明,提出的步长估计算法精度可达98.20%,与传统步长算法相比,误差显著降低。

An accurate step length calculation algorithm based on the combination of ultra-wide band(UWB)vector ranging and inertial sensing is proposed to meet the requirements of variable step length accurate measurement in complex environments.Aiming at the problem that the step length measurement accuracy based on the combination of inertial sensing is affected by the wearing method and the running time of the system,and the accuracy of pedestrian step length measurement and long endurance accuracy cannot be achieved,a step length algorithm combined with foot model and zero-speed detection is proposed.An inter-foot step length model is constructed based on the foot trajectory model when pedestrians are walking,and an accurate step length calculation formula is obtained.Zero-speed detection is performed according to the motion characteristics of the foot inertial sensor and UWB ranging is triggered at this moment.The angle calculated by the gyroscope is combined with the foot model formula to calculate the step length.Experimental results show that the accuracy of the step size estimation algorithm can reach 98.20%,whose algorithm error is about 5.8 times lower than the traditional step size estimation.