| Scraper conveyor,as one of the three equipment of underground working face,is widely used in the underground.One of its functions is to transport coal flow,but also restricts the overall shape of the three-machine face,and is the core equipment to realize the "three straight and two leveling" of the working face.The automatic straightening of the scraper conveyor is one of the key problems affecting the smooth development of intelligent mining,and straightness monitoring is the basis for solving this problem.At present,the straightness monitoring of the scraper conveyor in my country mainly relies on the indirect acquisition of the shearer's motion trajectory.It cannot directly monitor the straightness of the scraper conveyor in real time,and it cannot meet the technological requirements of "three straight and two leveling" in an intelligent working face.In addition,the working environment of underground coal face is very unfriendly to mining equipment has led to many problems in monitoring the condition of mining equipment at the working face.This thesis takes the intelligent working surface scraper conveyor as the research object,introduces advanced optical fiber sensing technology,the purpose is to realize the actual-time and precise detection of the straightness of scraper conveyor,and develops the optical fiber intelligent monitoring technology for the straightness of the scraper conveyor under complex conditions.The main contents of the research are as follows:(1)This paper analyzes the components of scraper conveyor and the movement under different working conditions,and establishes the bending model of scraper conveyor based on three machine constraints,and deduced the pose solution equation based on the relative angle of the central groove.On this basis,the paper puts forward a way to check whether the scraper conveyor is direct or not which based on the deflection displacement of middle trough;(2)The principle and features of fiber Bragg grating(FBG)transmission sensing are studied,and the transfer pattern of surface attached FBG strain sensing element is established.Comparison of FBG and resistance strain gauges placed in the same position,and the error correction relevance between the measured strain of FBG and the measured surface strain is obtained.The feasibility and check relationship of the pattern are justified by contrast experiment.the test compares and analyzes the FBG sensing transfer effect of variable paste parameters with anchor rod and nylon rod as the carrier,optimizes the sensing performance of surface-attached FBG,and improves the FBG strain sensing rate;(3)A surface-mounted FBG sensor based on a cantilever beam with uniform surface stress and strain and an elastic member was devised,and the equation between FBG characteristic parameters and sensor sensing parameters is deduced,and the stress-strain relationship of the cantilever beam under different loads are simulated and analyzed.The performance of FBG sensing element is gauged by interior calibration,and the test results indicate the FBG sensing element possess fine linearity and response rate in the devise operating range;(4)The angle measuring modle of the middle groove was set up,and the experimental method of straightness monitoring was designed independently.The linearity between the FBG wavelength and the angle of the middle groove,creep performance and error of FBG wavelength variation in the bending process of the middle groove were tested.The experimental data indicate that the linearity of FBG wavelength and angle is up to 0.999,and the long-term wavelength fluctuation is less than 3pm,and the error of the wavelength change is within 3%.The accuracy and real-time performance of the straightness perception are greatly improved,and this provides the research basis and technical reference for the overall shape control and intelligent cooperative operation of the three machines in the working face.This thesis has 61 figures,12 tables and 90 references. |
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