An enhanced positioning technique for underground pipeline robot based on inertial Sensor/Wheel odometer

Abstract

For traditional underground pipeline robot based on the inertial sensor/wheel odometer, the outliers of the data collected by the positioning system, the attitude error of the inertial sensor and the velocity measurement error of the wheel odometer are crucial factors affecting positioning accuracy of the pipeline robot, and have a significant influence on underground pipeline maintenance and pipeline mapping. To solve the above three error factors, an enhanced positioning method for the underground pipeline robot based on the inertial sensor / wheel odometer is proposed in this paper. Firstly, basic principles including robot attitude calculation based on inertial sensors, robot velocity calculation based on wheel odometer, position calculation of pipeline robot and outliers elimination based on extrapolation fitting method are introduced; secondly, the velocity information and attitude angle of the pipeline robot is corrected by prior-backtracking method; thirdly, the round-trip positioning data optimization method based on adaptive weight is designed to improve the accuracy of the whole pipeline robot positioning system; finally, three pipelines with different lengths are introduced to verify the effectiveness and reliability of the proposed method. The experimental results show that the error of position information is no more than 0.18%, 0.07% and 0.11% of survey length, respectively.