Research Of Underground Mine Personnel Positioning Technology Based On Fingerprint And Dead Reckoning

Safety is the most important task during the process of coal mine production.However,due to the complex environment of coal mine underground,the mining accidents cannot be avoided completely.After the disaster,the accurate positioning of miners is the key to the rescue operation.Therefore,it is very important to realize the personnel positioning in coal mine underground.This thesis focuses on the research of positioning technology in Wireless Sensor Networks(WSN)and inertial navigation which have already got obviously progress recent years,mainly learning the realization of fingerprinting positioning technology based on Levenshtein Distance,dead reckoning positioning technology,and the fusion of the above two technologies.The main contents are as follows:In the Off-line phase,on the basis of the original fingerprint database,the RSSI value is sorted to obtain a stable AP sequence according to the correlation between each AP.Then,a new fingerprint database is established,and clustering based on the strongest AP.In the On-line phase,the matrix dis is used to calculate the Levenshtein distance between the measured AP sequence and the vectors in the fingerprint database.The nearest neighbor matching point based on the minimum Levenshtein distance is proposed,which is used to location estimation.There are three steps in dead reckoning positioning technology: gait detection,step length estimation and heading estimation.In this thesis,the calculation method of gait and step length is introduced in detail,and the peak detection and nonlinear step size model are used to calculate the gait and step length.According to the characteristics of long and narrow in coal mine roadway,a simple method of combining the accelerometer and magnetometer is used to estimate the course roughly.In order to overcome the instability of fingerprinting and the error accumulation in dead reckoning technology,an error estimation based weighting fusion algorithm of the two positioning results is proposed,which use the Euclidean distance and the localization time of matching point to define the weights.Then,the position correction and weights update are carried out by using APs.Finally,this thesis introduces the hardware platform of the positioning technology.According to the experimental results,the positioning algorithm can improve the accuracy and stability of personnel positioning in coal mine underground.