The Location And Navigation System Of Substation Inspecting Robot Based On RTK GPS

This paper has studied the Substation Inspection Robot’s location and navigation system based on RTK(Real-time kinematic) GPS, the aim is to design an autonomous localization and navigation system for the State Grid Corporation of China, reduce the detection risk and enhance the patrolling quality.The emphasis of this paper lies on the robot’s autonomous localization, the realization of global electronic maps, the selection of path planning algorithms and navigation control algorithms’ design.According to the substation’s environment, we selected a robot platform and established the kinematic model. In view of the problem of autonomous localization,positioning principle, positioning accuracy and working condition of differential GPS were studied. To solve the intermittent disappearance of RTK GPS signal, adopts the differential GPS and odometer combined positioning mode, and form a data fusion method based on Kalman incremental model.The constriction of global digital maps was studied. Three sub-map fusion methods were proposed according to the GPS and total station, and the coordinate transform way based on differential GPS and total station proved feasible through testing. Establishing the regional sub-maps by total station, then complete the 2.5D global digital maps by that fusion method.Global path planning algorithm was researched. Rasterize and abstract the 2.5D global digital maps, then study the selecting form of various estimating function in A* algorithm. Based on the Simplified kinetic model, establish an Optimal Energy Consumption Model according to the robot’s actual working status, then choose an A* algorithm through practical simulation experiments.Design the navigation control algorithm. According to the positional deviation and course deviation between the robot’s current position and desired position, set up the relation between deviations and wheels’ speed increment. Then through simulation experiments and actual tests, the relationship proved right and optimal control parameters are gotten.At last, there are simulation experiments and actual tests, including the GPS position accuracy test, path planning experiments, data fusion experiments, navigation control algorithms test and global inspection test in the substation. Through global experiments in the substation, it proves that this inspestion robot is an autonomous localization and navigation system.