The Design Of Magnetic Navigation System For Substation Inspection Robot

This topic comes from substation inspection robot project of the company Chengdu Huituo.The robot is completed and has been put into practical operation in Mengdu substation. In order to ensure the inspection robot can work for a long time in the substation, this paper designs a magnetic navigation system which suitable for substation environment.Magnetic navigation system is an important part of substation inspection robot which can realize its navigation and positioning function. The system detects magnetic field by 3D MagIC and uses mileage encoder calculate robot mileage and eliminates the accumulated error by using RFID. In the process of navigating, in order to save power and improve the efficiency of robot, the magnetic navigation system is required to have the function of selecting shortest path. Magnetic stripe path laid within substation as the navigation map. The system uses STM32 as hardware development platform and choises FreeRTOS as software development platform.The modular design makes modules of the system independent from each others.The main research works are as follows:1. Build substation’s digital map. The digital map is built based on database MySQL Workbench. According to the substation map drawings given, we can select key nodes and define each section of the map, and then write the map datas into database with section as the unit.2. Shortest path planning. The system uses Dijkstra algorithm for the shortest path planning of robot. Based on the map data of substation, Dijkstra algorithm can search out the shortest path between two nodes which the current location of robot for the start node and the destination location for the end node.3. Design of magnetic navigation module. Magnetic navigation use STM32 as the main controller and detects magnetic field by 3D MagIC; CAN bus is selected to transfer information between magnetic navigation and central processing unit (CPU) of robot based on iCAN protocol.4. Design of positioning module. The system uses mileage encoder calculate robot mileage and eliminates the accumulated error by using RFID.The system is tested after all the design is completed.The test includes each module’s test and the whole test of system in substation.Finally, the test results are given through the analysisand the magnetic navigation system designed in this paper meets the design requirements.