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In order to reduce the number of operators in the working face of coal mines, an unmanned 5G ground remote control method for working face is proposed. The industrial cameras and sensors are set up in the working face, which transmit video, audio and sensor signals to the ground through the 5G network. The ground operator operates the equipment remotely, which transmits control commands to the working face through the 5G network, and controls the actions of the mine equipment. The wireless transmission distance and transmission bandwidth calculation method are proposed for unmanned ground remote control of the fully mechanized working face. The wireless transmission distance between the base stations at the two ends of the fully mechanized working face should not be less than 1/2 of the length of the fully mechanized working face. The total uplink transmission bandwidth required for unmanned ground remote control of the fully mechanized working face is proportional to the length of the fully mechanized working face, inversely proportional to the center distance of the hydraulic support, inversely proportional to the number of supports and cameras, and proportional to the transmission bandwidth required for the compressed video of a single camera. In order to reduce the demand for uplink transmission bandwidth for unmanned ground remote control of fully mechanized working face, it is possible to only transmit the camera videos of the adjacent shearers. The minimum bandwidth of uplink transmission required for unmanned ground remote control the fully mechanized working face is proportional to the number of cameras of the adjacent shearers, and proportional to the required transmission bandwidth of a single camera after video compression. The wireless transmission distance test method for the unmanned ground remote control system of the fully mechanized working face is proposed. The method is applied for the wireless transmission system such as 5G for the unmanned ground remote control system of the fully mechanized working face. Under the premise of ensuring transmission bandwidth, time delay and reliability, the wireless transmission distance is tested. The test shows that the uplink wireless transmission bandwidth of the base station shall not be less than 20 Mbit/s, and the wireless transmission distance shall not be less than 150 m. This study proposes the all-mine integrated information transmission network based on network hard slicing. Through network hard slicing, different channels are allocated for coal mine safety monitoring, mine monitoring, personnel and vehicle and equipment positioning, video monitoring, voice communication, 5G communication, etc. This method guarantees the high reliability and low time delay requirements of coal mine safety monitoring and mine monitoring, and unifies the underground information transmission network of coal mines. Moreover, it integrates multiple networks such as coal mine safety monitoring network, mine industrial Ethernet and mine 5G communication network.

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Mine unmanned vehicles are needed to reduce the number of coal mine underground operating personnel and to build safe, efficient, green and intelligent mines. The characteristics of mine unmanned vehicles are summarized as following points. The positions of underground operating personnel in coal mine are comprehensively identified. All mine vehicles are controlled. Mine track transportation equipment only needs one-dimensional positioning. The lighting condition is poor. The wireless transmission attenuation is large. There is no satellite signal. The electromagnetic environment is complex. The characteristics also include electrical explosion-proof, humid environment and water spray and dust. This paper analyzes the technical characteristics of mine vehicle positioning, such as ultrasonic positioning, laser position, radio positioning(including RFID, ZigBee, UWB, WiFi6, 5G), inertial navigation, simultaneous localization and mapping(SLAM), odometer and so on. This study puts forward a joint positioning method of mine vehicle, which is based on UWB and supplemented by inertial navigation, odometer and SLAM. This paper analyzes the technical characteristics of obstacle identification and distance measurement of mine unmanned vehicle, such as laser radar, millimeter wave radar, infrared camera, visible light camera, visible light binocular vision camera and so on. This study puts forward a multi-information fusion method of obstacle identification and distance measurement of mine unmanned vehicle. The method is mainly based on laser radar, supplemented by millimeter wave radar, infrared camera, visible light camera, visible light binocular vision camera and ultrasonic radar. When the road condition is complex and the automatic driving can not make decisions, the mine unmanned vehicle needs to automatically switch to the ground remote control mode. In view of the above situation, it is pointed out that the mine unmanned vehicle ground remote control technology based on 5G is the preferred scheme. However, the mine 5G wireless communication system has the problems of small wireless coverage radius and high cost. Therefore, it is suggested to study the application of WiFi7 in the mine vehicle ground remote control.

Copyright of Journal of Mine Automation is the property of Industry & Mine Automation Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

At present, the information carrier network used in coal mine is mainly 100 Megabit, Gigabit and 10 Gigabit mining Ethernet ring network. The time delay and reliability of the network are uncontrollable. Therefore, it is difficult to meet the needs of few people or unmanned operation in underground coal mine and remote control on the ground. Quality of service (QoS) can guarantee the real-time performance and reliability of the highest priority application. However, the real-time performance and reliability of the highest priority application can not be guaranteed when multiple interface signals are imported at the same time and the data volume is large, or when the previous data packet is being sent. In order to solve the above problems, the technical requirements of coal mine intelligent information comprehensive carrier network are proposed. The requirements include wide transmission bandwidth, short transmission delay, high reliability, long transmission distance, strong anti-interference capability, intrinsically safe explosion-proof, strong adaptability to grid voltage fluctuation, strong anti-fault capability, good protection performance, multi-service comprehensive carrying, etc. Based on the above requirements, a coal mine intelligent information comprehensive bearing network based on flexible Ethernet (FlexE) is proposed. This network allocates different channels according to the requirements of different services on bandwidth, time delay and reliability. The businesses include time sensitive and time insensitive video, time sensitive and time insensitive audio, personnel positioning, vehicle positioning, equipment positioning, safety monitoring, power supply monitoring, transportation monitoring, drainage monitoring, coal working face monitoring and heading face monitoring. The network integrates coal mine monitoring, positioning, video and audio into one network. The coal mine intelligent information comprehensive carrier network based on FlexE not only meets the requirements of different services such as ground remote control, personnel positioning and safety monitoring for bandwidth, delay and reliability, but also realizes the coal mine intelligent information comprehensive carrier network, reducing the maintenance difficulty and workload.

Copyright of Journal of Mine Automation is the property of Industry & Mine Automation Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)