Reconfigurable Locomotion System Of Coal Mine Detection And Rescue Robots

Nowadays, the quantity of coal production and consumption is huge in our county. But there are many high gas coal mines in our country and the coal mine production conditions are also poor, hence, coal mine disasters occur frequently, resulting in massive casualties and property losses. After the coal mine explosion disasters of gas and coal dusts, the terrain situation of the underground tunnels is complex and gases which are toxic and hazardous gather, what’s more, it is likely to take place a secondary disaster; therefore, it is not suitable for the rescue workers to enter. However, the experts and policy makers on ground urgently need to learn about the underground situation for making a timely decision. Let the coal mine detection and rescue robots enter into the underground first to detect the damage situation of the underground tunnels and to measure the concentration of the hazardous gases, feeding back the acquired information to the control center in the form of images and data to provide decision basis for the experts on ground, in this way, a high efficient rescue could be implemented to minimize the casualties and property losses in the maximum under the premise of ensuring the safety of the rescue workers. So it is an urgent task to develop a new kind of robot locomotion equipment that could adapt the special environment underground in order to guarantee the coal mine production safety.Through the analysis and integration of the typical robotic locomotion mechanisms both at home and abroad and also taking into account of the particularities of coal mine disasters areas, a wheel and track alternative coal mine detection and rescue robot is put forward. The greatest innovation of the robot lies in:the wheel linkages mechanisms are added to both sides of the tracked robot, thus the robot could control the fall and rise of the wheel mechanisms through the motion of the linkages mechanisms; and in this way the robot realizes the switchover of the two locomotion modes. While traveling in underground, the robot could choose to use wheel or track to drive flexibly according to the different road conditions.Firstly, the building and assembly work of the robot’s digital model is completed in CATIA, secondly, kinematics analysis of the newly built robot model is performed with mathematical methods, and then the robot model is imported into ADAMS with SimDesigner which is used as the interface software between CATIA and ADAMS to perform the motion simulation, finally, the failure reasons of the simulation are analyzed. All this work has laid a foundation for the proceeding of the following study.To confirm the mechanism feasibility of the designed robot and to visually present the motion principle of the robot, a simplified robot model is established in ADAMS and then the motion simulation of wheel and track switchover operation is performed. Finally, through the analysis of the curves derived from the simulation, the established kinematics model of the robot is proved to be correct.Through the analysis and summary of the design experiences on existing PID controllers and fuzzy controllers, a new Fuzzy-PID controller is then put forward to control the motor’s rotational speed of the coal mine detection robot TUT-CMDR. The Fuzzy-PID controller is designed in MATLAB/SIMULINK environment and parameterized quantization and scaling factors are proposed to solve the problem of different fuzzy linguistic basic universe for different final value of the step signal; finally, some improvement is made on the existing fuzzy control rules. The new Fuzzy-PID controller is proved to show a better control performance on motors through the simulation.