Research On High-Precision Localization Technology In Underground Coal Mine Based On Utral Wideband

With the· development of industrial internet of things and artificial intelligence technology in the field of coal mines,the location information of underground miners and equipment has become a very important basic information.At present,WiFi,ZigBee,Bluetooth and other wireless technology are widely used to locate underground.however,due to the poor localization accuracy,it can not meet the increasing demand for high-precision localization in underground coal mines.The Ultra Wideband(UWB)technology has the advantages of high time resolution,high ranging accuracy,strong penetration and strong anti-multipath capability,which is the advanced technology to achieve high-precision localization in recent years.Therefore,the high-precision underground localization technology based on UWB was studied to meet the high-precision requirements.As localization technology on the basis of TOA range was adopted,the Asymmetric Double Sided Two-Way Range(ADS-TWR)algorithm was applied through the error analysis of each ranging algorithm.ADS-TWR can eliminate the effect of unsynchronized clocks between ranging nodes on the accuracy,and suppresses ranging errors caused by clock drift.Based on the realization of ADS-TWR in software and the application of UWB signal transceiver chip DW1000 in hardware,a set of underground anchor and tag node was designed and relized.On the application of anchor and tag,the research of the relationship between DW1000 chip parameters and ranging performance was implemented.Finally,the parameter values suitable for underground high-precision localization are selected to fulfill the ranging accuracy of 20cm and the communication distance of 300m.Aiming at the problem that a large number of invalid communication was generated by the tag broadcasting request frame when starting the localization in the underground multi-anchor layout,a tag region determination strategy based on ADS-TWR was proposed,which made the tag communicate with anchors in region only and avoided tag try to connect with anchors repeatedly,that are not participating in localization.Thus,it greatly reduced the communication overhead.At the same time,the tag region abnormal self-checking and region correction mechanism were introduced to ensure the accuracy of region determination.On the basis of high-precision ranging and region determination strategy,a UWB-based underground multi-anchor localization system is designed and tested in a simulated environment.Through experimental data analysis,it is shown that triangular centroid algorithm can effectively weaken the effect of ranging error on localization precision and achieve the localization precision of 15cm.Moreover,it makes the average of localization error reach 6.144cm,and reduce to approximately 45.4%relative to the total average ranging error 11.26cm.