Research On Rfid Method For Coal-rock Interface Facing Fully Mechanized Mining Face

The unmanned and intelligent development of underground fully mechanized mining face is the only way to improve coal production efficiency and ensure the safety of operators.To achieve this goal,we must first solve the problem of intelligent identification of coal-rock interface,so that the shearer cuts the coal seam along the interface between the coal wall and the rock wall as much as possible,and adjusts the shearer drum in time when cutting to the rock wall.Cutting depth.However,the existing coal-rock interface identification technology generally determines the rock formation based on the change of the contact medium,and it is difficult to obtain the coal-rock interface information in advance,so that the cutting strategy can only be adjusted when the pick cuts to the rock wall,which is easy to cause pick damage;emerging Noncontact identification technologies such as terahertz and hyperspectral have the problems of high cost and low environmental adaptability.In view of the above problems,this thesis conducts basic research on the application of the coal-rock interface identification method based on RFID(Radio Frequency Identification)technology for the actual working conditions of the fully mechanized mining face,and focuses on exploring the ability of RFID technology to identify the coal-rock interface.And the adaptability to the environment of the fully mechanized mining face lays the foundation for the future application of RFID technology in the fully mechanized mining face of coal mines.The main research work is as follows.1)The three-dimensional electromagnetic simulation software HFSS is used to simulate the electromagnetic characteristics of various common coals and rocks,and the differences between the radio frequency signals of bituminous coal and sandstone are analyzed.Key parameters of interface RFID(phase and received signal strength).2)A coal-rock interface identification system based on RFID is designed.Firstly,based on the RFID backscattering mechanism,the basic structure of the coal-rock interface RFID system is designed.The influence of obstacle environment and passive tag status on the RFID system is analyzed respectively.Finally,according to the analysis results,the RFID system is optimized.The research results show that the obstacle environment will make the RFID eigenvalue fluctuate,but in general,with the increase of the frequency,it still shows a decreasing trend;the tag displacement,rotation angle,bending degree,quantity,etc.Certain influence;the optimized system has higher stability and accuracy.3)The static performance of the RFID system for coal-rock interface is studied.The identification performance of radio frequency signal on coal and rock types is studied through experiments.Combined with the differences of coal and rock itself,the radio frequency signal of coal rock with different water content and different mineral content is experimentally analyzed.Based on the experimental results that the radio frequency identification system can identify coal and rock materials,the influence of coal rock samples with different coal wall thicknesses and different interface depths on the radio frequency signal is further studied.The results show that the radio frequency identification system can distinguish the existence of rocks in the coal seam within the identifiable distance.4)The dynamic performance of the coal-rock interface identification system is studied.Firstly,the identification performance of the RFID system on the graded coal wall is studied;then the coal-rock interface RFID system is installed on the vibration exciter and the synchronous belt,and the three typical dynamic factors under the fully mechanized mining face: rotation angle,vibration The frequency and operating speed are respectively studied,and the results show that the characteristic trend of the radio frequency signal for identifying the gradual coal wall in the dynamic environment is consistent with that in the static environment,which verifies that the radio frequency identification system is stable and can adapt to the mechanical vibration and coal vibration in the fully mechanized mining face.Rock shock and other conditions.The paper has 65 figures,19 tables,and 91 references...