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Facing the demand of autonomous path correction of the road-header working underground, a control law was designed and simplified based on the position and orientation deviation model of the road-header against its aimed walking trajectory.Reasonable Lyapunov function is constructed to prove the convergence of the position and orientation deviation that resulted from the designed control law.Based on a certain real time position and orientation detection strategy for the road-header, the possible errors exist during posture adjustments are summarized and classified into two parts: one is the main execution error of the road-header and it is presented by the slip rate of tracks; the other is the main observation error and it is identified as the position and orientation measurement errors.This paper proposed to take advantages of the statistical characteristics of these errors, which is obtained by a certain number of experiments or deductions instead of rigorous theoretical analysis.The SVD-unscented Kalman Filtering is used to modify the commands that are given originally by the controller so as to deduce and reduce the influence of process error and observation error in the process of position and orientation adjusting.The simulation results show that the proposed path tracking control strategy can effectively realize the transition of the road-header to the target roadway in limited adjustment period, and the corresponding recommended speeds of the driving wheels vary continuously and stably in the whole process.The negative influence of process error and observation error is effectively weakened by commands modification based on SVD-unscented Kalman Filtering.The obtained moving trajectory of the road-header coincides with the planned path very well during the adjustment, which is of great repeatability.This proves that the proposed strategy is of great potential to be applied experimentally in underground real road heading scenario.

The working condition of fully mechanized roadway is complex and also has the particularity of limited boundary. Aiming at the problem of heading angle correction of crawler support vehicle affected by the slip rate of coal roadway floor, an autonomous navigation method of crawler support vehicle is proposed in the grid scene of confined roadway space. The grid theory is used to divide the operational environment of fully mechanized roadway, and the heading reference influence degree is proposed as the simplified index of roadway model. Based on the motion characteristics of the crawler support vehicle, whose autonomous navigation motion model is established in the grid scene, the construction of mathematical model and the stability analysis of its hydraulic driving system are carried out. Adaptive control of the track speed on both sides of crawler support vehicle is realized to meet the accuracy requirements of the heading angle with the combination of fuzzy control and PID algorithm, which helps to complete the course correction of crawler support vehicle under the influence of different slip rates. The AMESim and MATLAB/Simulink semi-solid physical simulation model is built to simulate and verify the hydraulic walking system of crawler support vehicle. The simulation results show that the accuracy of the navigation algorithm is higher than that of the traditional PID control algorithm, and the track speed regulation process is more stable and less vibrational, which verifies the reliability and advancement of the autonomous navigation method based on the regional grid scene.

At present, detection error of pitch angle of roadheader is mainly compensated by manually controlling front blade and rear support of roadheader, the compensation range is very limited, and the efficiency, control precision and automation degree are low. In view of the above problem, mathematical model of pitch angle and actuator of boom roadheader were established, and the method was determined that adjusting position and posture of boom roadheader by using PID controller to control displacement of front shovel and rear support of the roadheader. AMESim was used to establish complete hydraulic model of actuator of the roadheader. The AMESim simulation shows that response time of the system is less than 3 s and the control error of hydraulic cylinder displacement is less than 2 mm, so the basic performance of the pitch angle control system is verified. The Simulink simulation results verify that the pitch angle control system has short response time, small tracking error, and good dynamic tracking performance.

In order to obtain influence regularity of cutting head load to deviation angle of boom-type roadheader during cutting process, a dynamical model of roadheader's deviation angle was established. According to input problem solved by the model, a calculation method of the cutting head load was proposed, and relationship between the cutting head load and pressure of driving cylinders and cutting position of cutting arm was obtained by simulating calculation. The variation of roadheader's deviation angle during cutting process was simulated and analyzed, and influence regularity of the cutting head load to the deviation angle in different cutting conditions and different cutting positions of the cutting arm were obtained: In horizontal cutting condition, the deviation angle increases with increasing of the cutting head load , and it reaches to the maximum when the horizontal angle of the cutting arm is 14°; in vertical cutting condition, the deviation angle decreases with increasing of the cutting head load, and the larger vertical angle of the cutting arm is, the smaller the deviation angle is.

In order to realize unmanned and high accurate detection of position and attitude of boom-type roadheader on fully mechanized excavation face, a position and attitude detection system of roadheader based on ultra wide band ranging technology was proposed, calculation methods of positioning coordinate and attitude angle of roadheader were deduced based on the system, and affection of distance and angle between base stations on positioning accuracy and affection of distance between positioning points of roadheader on attitude angle detection accuracy were analyzed by Matlab simulation. The simulation results show that positioning accuracy of the system decreases with increase of distance between base station and positioning point of roadheader; positioning accuracy of the system increases with increase of distance between base stations; under the case of angle between base stations in yoz plane is 60°, positioning accuracy of the system is higher than the one when the angle is 0° or 90° respectively; distance between base station and positioning point of roadheader has no significant affection on attitude angle detection accuracy; and attitude angle detection accuracy increases with decrease of distance between positioning points of roadheader.