A Novel Method Improving the Accuracy of Attitude Estimation of All-position Welding Robot

In recent years there have been excellent results in attitude estimation techniques, which aim to offer precise posture information for various industrial robots. Various tasks especially the inspections and welding on the eroded surface of large-scale hydraulic turbine blade are performed by mobile robots. In those case, the robot moves on curved surfaces along the predetermined route and it is necessary to know its real-time attitude angle for the welding task. In this paper, we propose a novel approach for improving the accuracy of attitude estimation of all-position welding robot using low-cost MEMS inertial sensors. The gyro drift error caused by temperature or bias instability is estimated when the welding robot is at zero velocity in the whole course of navigation. The performance of the proposed approach will be analyzed through a series of experiments by the all-position welding robot developed in our laboratory. To show the performance of the presented method, the experimental results obtained by a low-cost Inertial measurement unit (IMU) and a high-accuracy IMU were compared.