To solve the problem of the severe decrease in positioning accuracy caused by the accu-mulation of errors in the pedestrian inertial navigation system over time,a three-dimensional(3D)pedestrian inertial positioning algorithm based on the auxiliary information of inter-foot distance is proposed.Based on zero velocity update(ZUPT),the algorithm utilizes an ultrasonic ranging module installed on the feet to measure the relative distance between the pedestrian's feet in real-time,constructing a constraint model based on ultrasonic ranging for inter-foot distance.In addi-tion,the random forest algorithm is used to recognize pedestrian motion patterns.For stairway scenarios,the height is calculated based on the step height and inter-foot distance,ultimately a-chieving 3D pedestrian inertial positioning.The 3D positioning experiment is carried out on the ac-tual route.The data show that the plane closed-loop error of the proposed algorithm is 0.64％of the total distance,which is decreased by 55.56％compared with the ZUPT algorithm,and the height error is 0.06 m,which is decreased by 64.70％compared with the ZUPT combined with barometer algorithm.In general,the 3D positioning with navigation error within 0.50％of the to-tal distance can be achieved.These results demonstrate the practical engineering value of the pro-posed algorithm.
维普
万方数据