Research On VR Simulation System And Key Technology Of Fully Mechanized Coal-mining Face Under Complex Coal Seam Conditions

Coal mine intellectualization is the premise and foundation of building intelligent mine.It is an important link in coal mine intellectualization to realize the accurate monitoring of the fully mechanized coal-mining face "three machines" equipment(shearer,hydraulic support and scraper conveyor),and the construction of a fully mechanized coal-mining face VR(Virtual Reality)monitoring system is one of the core technologies.Most of the existing monitoring systems are based on the ideal level,and the research methods are out of reality.It is difficult to build a fully mechanized coal-mining face with complex coal seam conditions,and it is also difficult to realize the accurate coupling of equipment and coal seam.In addition,the coal seam can’t be automatically updated,resulting in the continuous mining of the whole virtual fully mechanized coal-mining face can’t be realized.Therefore,this paper studies the fully mechanized coal-mining face VR simulation system and key technologies of under complex coal seam conditions,aiming to establish a more real virtual simulation system,and then analyze the equipment and coal seam,so as to realize the purpose of guiding the mining process.The main research contents and conclusions are as follows:(1)In the stage of building a fully mechanized coal-mining face VR simulation system,the modeling method of coal seam is studied,and the comprehensive modeling method of coal seam is determined.The physical engine is used to make the equipment have the gravity attribute,the collision body is used to increase the contact effect between the equipment and coal seam.According to the coordination method between the equipment,the model is constrained and coordinated.Based on the virtual engine Unity 3D,the fully mechanized coalmining face VR simulation system under complex coal seam conditions is established.The simulation system enables the equipment and coal seam have real gravity and contact properties,and enables the equipment have real motion elements and characteristics of movement under complex conditions.(2)The construction method of the fully mechanized coal-mining face "three machine" equipment working space is studied.The key information points are marked on the fully mechanized coal-mining face "three machines" equipment.In the process of system simulation,the key information points are recorded in real time,and the working spaces of hydraulic support,scraper conveyor and shearer are established respectively.This method can realize the extraction and characterization of the working attitude of the "three machine" equipment,and it can be expressed in three-dimensional space.(3)The target cutting trajectory of shearer is predicted.The historical cutting data of shearer generated in the process of simulation system operation is composed of training data set.The cutting trajectory of the shearer is predicted by two machine learning methods of BP neural network and extreme learning machine,and the accuracy of the two methods is analyzed and evaluated.The results show that the prediction effect of extreme learning machine is better than that of BP neural network,and it is a better prediction model.(4)The simulation experiment is carried out for the simulation system.The prototype system is established,and the simulation experiments are carried out on three schemes: shearer memory cutting,manual intervention shearer memory cutting and shearer autonomous cutting.The initial coal seam model and dynamic coal seam model are established by using the method of reverse reconstruction.The remaining coal quantity and cutting rock quantity are obtained,and the cutting scheme is evaluated by calculating its volume.The results show that: shearer autonomous cutting scheme is the optimal scheme,which can achieve the maximum coal cutting and minimum rock cutting.The simulation system established in this paper solves the problem that it is difficult to couple the equipment and coal seam accurately.It can simulate the "three machines" equipment under complex coal seam conditions,and can test and evaluate the cutting schemes of various shearers.