| As one of the most important transport equipment in underground mining, the research of autonomous control technology for LHD (load-haul-dump) is very popular. Autonomous control of underground LHD is mainly reflected to unmanned and automatic working. In this thesis, LHD is taken as object of the study, and the corresponding research on autonomous control of driving and dumping is conducted.After summing the advantages and disadvantages of articulated steering vehicles, the steering radius and turning curve which focus on the curve segment and the line segment are studied. The resistance moment and steering time are derived from the sight of autonomous control. The dynamics system is analyzed and the constraint relations between the steering cylinder and the steering angle are discussed. All of these are designed to provide a theoretical basis for autonomous driving algorithm.The location method for LHD which combined with the relative location of path prediction and the absolute location of "pseudo GPS" is introduced in the field of autonomous control firstly. The navigation strategy of main target path planning and local obstacle avoidance goal path planning under unified navigation coordinate is put forward. The trajectories parameters and curves of the LHD are defined during its driving in the tunnel. The trajectory mode is derived and the relationships of various parameters are drawn up, which provided a theoretical basis for designing trajectories tracking control algorithms. The deviation of the lateral position, the heading angle deviation and the deviation of the heading angle are taken as the feedback corrections. The control algorithm model is established based on the multi-information fusion and threshold control. The autonomous navigation experiments are realized by controlling the velocity and the steering angle.Based on MATLAB/Simulink, the autonomous control model is set up with the steering dynamics of the LHD. With the main target path and the local obstacle avoidance path planning, the autonomous control algorithm of autonomous driving is simulated under linear, circular and the sine curve. The result shows it could avoid the obstacles in the path effectively, which can quickly, accurately and stably realize the control of autonomous driving.How to acquire and update the pitching angle, roll angle and yaw angle of LHD by the inertial measurement unit using quaternion method is introduced. The lifting hydraulic system is simulated and the lifting pressure is computed conbined with the inherent characteristics of hydraulic valves. The weight of ore in the bucket is calculated which can use to judge whether or not dumping. The process of control for autonomous dumping is also explained.For the autonomous control, sensor system with odometer, angle sensor and IMU is set up. The communication system based on CAN bus and Ethernet is also established. The data form the laser scanning sensor while scanning tunnel are pre processed in order to overcome the filtering and eliminate the influence of large measurement errors, which is called virtual scanning measurement pre-processing technology. Besides, an embedded intelligent control platform with Linux operating system is adopted. The process of software design and programming platform are introduced, which combines the characteristics of the lowest level executive controller. The basic autonomous control platform is formed with above.At last, the paper introduces the autonomous control platform KCY-2 LHD. The Electronic injection diesel engine based on J1939 bus control and automatic gearbox based on APC120 are choosen.The test of autonomous control is carried out under the condition of simulated underground tunnel, which verifies the feasibility of the algorithm. The data are analyzed and summarized, and the algorithm is applied to the underground tunnel environment. Finally, the experiment of autonomous control of dumping is carried out and the aim has been achieved. |
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