Position and attitude calculation method of anti-impact drilling robot based on spatial array inertial units

Anti impact drilling robot is a key equipment for underground rock burst relief in coal mine and its accurate position and attitude determination is the basis and premise for realizing unmanned pressure relief operation. By analyzing the characteristics of mobile robots and coal mine equipment positioning technologies, a position and attitude calculation method for anti-impact drilling robot based on spatial array inertial units is proposed. Based on the analysis of the types and sources of positioning errors of conventional inertial sensing units, the data fusion model of spatial array inertial units is established to derive the fusion equations of angular velocity and proportional acceleration, and the position and attitude calculation process of spatial array inertial units is designed. By analyzing the actual operating conditions of the anti-impact drilling robot, the curve motion trajectory of the drilling robot is simulated, and the position and attitude calculation method is simulated and analyzed. The simulation results show that the proposed method is better than the original method and the differential method in terms of displacement cumulative error and attitude angle average absolute error. In order to verify the feasibility of the proposed method, a motion simulation test bench of mobile carrier is built according to the actual situation of the site, and the trajectory tracking and monitoring experiments are carried out. The results show that the position and attitude calculation results of the spatial array inertial units are better than those of other two methods. The cumulative displacement errors in the x,y and z axes are 5.83,8.76 and 0.84 cm respectively, and the average absolute errors of yaw angle, pitch angle and roll angle are 0.15°, 0.07° and 0.06° respectively. In order to further verify the practicability of the proposed method, the position and attitude determination experimental platform of the anti-impact drilling robot is built, and the straight-line operation experiment of the anti-impact drilling robot is carried out. The experimental results show that the average absolute errors of yaw angle, pitch angle and roll angle of the drilling robot based on the proposed method are all less than 0.5°. The average errors of displacement in the x, y and z axes are less than 2.00 cm. The position and attitude calculation errors meet the actual requirements, and the feasibility and effectiveness of the proposed position and attitude calculation method for the anti-impact drilling robot are well verified.