Research And Design Of Logistics Vehicles Positioning And Monitoring System Based On GPS/CDMA/Google Maps

When society is in progress,and science and technology are developing,following the pace of the Internet some new industries begin to rise rapidly.Especially in recent years,the speed of development of e-commerce industry is very surprising but reasonable,such as Taobao and Jingdong.In short,the development of e-commerce is bound to bring a second industrial revolution.However,with the gradual maturity and application of online shopping,the resulting traffic pressure is no doubt a further impact on the existing urban traffic problem.Such as in the Single's Day,the warehouses of major express delivery business are filled with goods,which exerts an impact on traffic pressure.And the monitoring and management of existing logistics vehicles is not perfect.There are many problems,such as low efficiency of transportation,high transportation cost,poor real-time scheduling,difficulty in collecting traffic information,unable to grasp the exact position of the vehicles at any time,speeding,running car for private purpose and disorderly parking.Therefore,how to effectively monitor and manage the vehicles in the process of distribution is an important problem that logistics enterprises and the society need to urgently solve.In this paper based on the technology of GPS,CDMA,and Google Maps,integrated by using the technology of computer network,MFC multithreading,Kalman filter,WEB front-end and database storage,etc.,and combining with the characteristics and actual demands of logistics enterprises,a set of logistics vehicles positioning and monitor system is researched and designed.The system consists of four sub-systems: positioning processing subsystem,communication transmission subsystem,Kalman filter subsystem and geographic information subsystem.For positioning processing subsystem,firstly it makes full use of MFC multi-threading technology to extract GPS navigation messages from controlled vehicles;Secondly it uses the function of string manipulation to obtain longitude,latitude,speed and time of the vehicles;Thirdly in the onboard computer database it utilizes the ODBC interface to store the datum that can be used for the follow-up system.For communication transmission subsystem,it mainly uses the AT command to set up a communication bridge to support TCP/IP between the mobile terminal and the monitoring center of the vehicle,which can rely on the communication bridge to transfer information.For Kalman filter subsystem,first it aims at the running characteristics of the vehicle to establish GPS system model;Then it adds road information constraints into the system model,which can be deduced adaptive filter equations of exponentially-weighted fading memory with road information constraints;Finally,the GPS dynamic positioning datum of the vehicles go through the filter to improve the system of positioning accuracy and tracking performance.For geographic information subsystem,it takes advantage of Google Maps API to load Google Maps,and then by using the technology of WEB front-end and My SQL data storage realizes the function of vehicle positioning,real-time monitoring and historical trajectory playback.Through the online debugging,the logistics vehicles positioning and monitoring system designed by this paper can meet the needs of logistics enterprises.And due to the Google Maps is free to use,which can save the map development cost of logistics enterprises.In conclusion,the system can improve the operation efficiency and safety rate of logistics enterprises vehicles.What's more,it can effectively eliminate the phenomena of vehicles speeding,running car for private purpose and disorderly parking.And it has a good economic benefit.