Research On Tracking Assistance Method Of Guided Transportation Train Based On Autonomous Combined Positioning

In order to adapt to the new urbanization development of the country and realize the optimization of the urban transportation system,the Guide Transportation Train(GTT)came into being.As a new type of transportation,GTT fully combines the advantages of urban rail transportation and road transportation,and will play an extremely important role in the field of urban transportation in the future due to the advantages of short construction period,large passenger volume,energy saving,environmental protection,and intelligence.GTT relies on various on-board sensors to identify the dotted line on the road to achieve tracking,and there are two sets of equipment are used for positioning and tracking,which leads to higher costs.In addition,domestic and foreign research on the tracking of GTV pays less attention to lateral offset tracking at present,while there is no fixed track constraint during the operation of GTT,there are potential safety hazards when the lateral deviation is large.Aiming at the above two points,this thesis designed a low-cost high-precision tracking assistance method based on autonomous combined positioning,this method combined the characteristics of fixed transportation routes and low floors of GTT,a combined positioning system was built by using low-cost satellite receivers,inertial navigation equipment and electronic tags to obtain high-precision train position information,the map matching technology was used to correlate the position information to the actual road network,so as to realize the detection of the lateral offset distance of the train.The research work of this thesis is as follows.Firstly,this thesis introduced the current development status of the typical guided transportation system,summarized the vehicle relative position acquisition method,train positioning technology at home and abroad.Combined with the characteristics of GTT,the feasibility and functional requirements of high-precision tracking assistance method based on autonomous combined positioning were analyzed.Then,aiming at the problem of obtaining the position information of the train on the lane,the cubature Kalman filter(CKF)was used to filter and merge the positioning data to realize the preliminary positioning function of the train based on GPS / SINS;for the problem of error accumulation in the combined positioning system,the fixed-point correction of the position information was realized by using the RFID-based electronic tag.On this basis,the map matching algorithm based on Hidden Markov Model(HMM)was improved,it was used to match the high-precision electronic map to realize the detection of the train lateral offset distance.Finally,this thesis designed and built a real-vehicle experimental platform,and verified the effect of the algorithm proposed in this thesis through real car experiments.The experimental results showed that the tracking assistance method based on autonomous combined positioning designed in this thesis could achieve sub-meter-level positioning accuracy and provided the position information of the train that met the requirements for detecting the lateral offset distance of the train,and the accuracy of the GTT lateral offset distance detected within a certain deviation distance range was more than 95%,which provided theoretical support for the accurate tracking of GTT along the "virtual trajectory".59 charts,10 tables,50 references.