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The automatic perception and alarm method for coal mine rock burst and coal and gas outburst is an effective measure to timely detect accidents and emergency rescue, reduce casualties, avoid or reduce secondary accidents such as gas and coal dust explosions, and curb delayed, missed, and concealed reporting of accidents. It is difficult to perceive coal mine rock burst accidents, and there is currently no automatic detection and alarm method for coal mine rock burst accidents. Coal mine rock burst accidents are mainly discovered manually. At present, there are only automatic alarm methods for coal and gas outbursts based on methane, wind speed, and direction sensors. There are problems such as slow response speed and inability to detect significant increases in methane concentration before methane sensor damage. A method for image perception and alarm of coal mine rock burst and coal and gas outburst has been proposed. Based on the image features of coal mine rock burst and coal and gas outburst temperature, color, depth, burial, etc., the method recognizes coal mine rock burst and coal and gas outburst. Based on the changes in gas concentration in the roadway space and mining face, the method distinguishes between rock burst and coal and gas outburst. If the gas concentration rapidly increases over a large area, it is judged as coal and gas outburst, otherwise it is judged as rock burst. This method has the advantages of intuitiveness, fast response speed, non-contact, wide monitoring range, simplicity and reliability, and can intuitively record the real situation of coal mine rock burst and coal and gas outburst. When the coal mine rock burst and coal and gas outburst accidents are alarmed, the personnel on duty in the control room can immediately confirm the accident through video recording and carry out emergency rescue in a timely manner. A method has been proposed to reduce the impact of coal mine rock burst and coal and gas outbursts on image perception, including multi point arrangement of cameras, setting of cameras at higher positions, timely transmission of video data, and multi-point arrangement of methane sensors.

The paper analyzes the image characteristics of the thrown coal and rock when rock burst and coal and gas outburst occur. ① The coal and rock thrown out during rock burst and coal and gas outburst are mainly black, but the underground equipment of the coal mine is generally not black. Therefore, nonblack mining equipment can be used as the background and color cameras can be used to identify coal and rock. ② The normal coal falling speed, the moving speed of shearer, roadheader, and the moving speed of underground personnel and vehicles are far less than the speed of coal and rock thrown out in the event of rock burst and coal and gas outburst. Therefore, according to the speed characteristics, the interference from normal coal falling, movement of equipment such as shearer and roadheader, and movement of underground personnel and vehicles can be eliminated. ③ The explosion of gas and coal dust will also cause the objects in the roadway to have a high speed in a short time, accompanied by high brightness. But the rock burst and coal and gas outburst will not produce high brightness. Therefore, according to the average image brightness, the interference of gas and coal dust explosion can be eliminated. The paper proposes a color camera set method. The camera of the heading face should be set at the roof of the heading roadway or near the roof on both sides of the heading roadway. The camera of the working face should be set on the top of the hydraulic support. The paper puts forward a coal mine rock burst and coal and gas outburst perception alarm method based on color image. ① The color camera with fill light shall be set at the roof of the heading roadway or near the roof on both sides of the heading roadway, and at the top of the hydraulic support of the working face. The nonblack mining equipment is used as the background. ② The method monitors and identifies whether the color of the color image has changed greatly. ③ If the image color changes significantly, the average brightness of the image is identified, otherwise the monitoring of the identified image color change continues. ④ If the average brightness of the image is less than the set brightness threshold, the movement speed of the object causing a large change in the image color is identified, otherwise the monitoring of the identified image color change continues. ⑤ If the movement speed of the object is greater than the set speed threshold value, the methane concentration in the monitoring area is identified, otherwise the monitoring of the identified image color change continues. ⑥ If the methane concentration rises rapidly or reaches the alarm value, the coal and gas outburst alarm will be given. Otherwise, the rock burst alarm will be given. The method has the advantages of non-contact, wide monitoring range, low cost, convenient use and maintenance.

The burial image features of a large amount of black coal rock thrown out during rock burst and coal and gas outburst are analyzed. The features include changes in the area of the monitoring area's color and corresponding graphics, changes in the number of colors and corresponding graphics, changes in the shape of colors and corresponding graphics, and anomalies in burial positions. When a disaster occurs, it will result in a reduction in the area of non-black areas within the monitoring area, with a significant reduction in speed and acceleration. Based on the above feature, a perception alarm method for rock burst and coal and gas outburst is proposed based on the features of color and its corresponding graphic area changes. When a disaster occurs, it will result in a reduction in the number of non-black areas within the monitoring area, with a significant reduction in speed and acceleration. Based on the above feature, a perception alarm method for rock burst and coal and gas outburst is proposed based on the features of colour and its correspoding graphic number changes. When a disaster occurs, it will cause a decrease in the circularity, rectangularity, and area-to-perimeter ratio of non-black graphics within the monitoring area, with a significant reduction in speed and acceleration. Based on the above feature, a perception alarm method for rock burst and coal and gas outburst is proposed based on the features of color and its corresponding graphic shape changes. When a disaster occurs, it can lead to underground coal mine personnel, hydraulic support at the top and near the top being buried by coal and rock. Based on the above feature, a perception alarm method for rock burst and coal and gas outburst is proposed based on the features of abnormal burial position. The above perception alarm method for rock burst and coal and gas outburst based on burial image features has the advantages of fast response speed, non-contact, wide monitoring range, low cost, and convenient use and maintenance.

The paper puts forward a perception and alarm method of rock burst and coal and gas outburst based on temperature. The infrared thermal imager is used to monitor the temperature of objects, and the methane sensor is used to monitor the concentration of ambient methane. When the temperature of the objects is higher than the ambient temperature of the coal mine and the temperature of the exposed coal rock, and the number, volume and area of objects that are higher than the ambient temperature and the temperature of the exposed coal rock are large, it is determined that rock burst, coal and gas outburst, mine fire or gas and coal dust explosion accidents have occurred. The temperature of the high temperature object is further determine. If it is greater than the set threshold, it is determined that a mine fire or a gas and coal dust explosion accident has occurred. Otherwise, it is determined that a rock burst or a coal and gas outburst accident has occurred. The change of methane concentration is further analyzed. If the methane concentration rises rapidly, it is determined that a coal and gas outburst accident has occurred. Otherwise, it is determined that a rock burst accident has occurred. The paper puts forward a perception and alarm method of rock burst and coal and gas outburst based on velocity. The lidar, millimeter-wave radar, ultrasonic radar, binocular vision camera are used to monitor the moving speed of objects. The methane sensors are applied to monitor the concentration of ambient methane. When the moving speed of the object is not less than the set threshold, it is determined that rock burst, coal and gas outburst or gas and coal dust explosion accident have occurred. The number, volume and area of objects with abnormal velocity is further determined. If the number of objects with abnormal velocity is small, the volume and area are small, it is determined that a gas and coal dust explosion accident has occurred. If the number of objects with abnormal velocity is large, the volume and area are large, it is determined that a rock burst or a coal and gas outburst accident has occurred. The changes of methane concentration are further analyzed. If the methane concentration increases rapidly, it is determined that a coal and gas outburst accident has occurred. Otherwise, it is determined that a rock burst accident has occurred. A multi-information fusion method for perception, alarming and judging disaster source of rock burst and coal and gas outburst is proposed. The method monitors and integrates various information such as temperature, speed, acceleration, burial depth, sound, air pressure, wind speed, wind direction, dust, methane concentration, equipment status, micro-seismic, geosound, stress, infrared radiation, electromagnetic radiation and images so as to monitor the pressure and coal and gas outbursts. The source of the disaster is determined through the magnitude of parameter changes at different locations, the sequence relationship and sensor damage.

Coal mine gas and coal dust explosion will produce explosive sound. Coal and gas outburst will produce the sound of coal cannon and the supports will produce squeaking and cracking sound. Rock burst will produce huge rock breaking sound and vibrations. Coal mine water inrush will produce 'hissing' water sound, and a large amount of water inrush will produce water flow sound. Coal mine roof fall will produce roof cracking sound, coal rock hitting the ground sound and support damage sound. According to the characteristics of the sound of extraordinary accidents in coal mines, the alarm methods of accidents of mine gas and coal dust explosion, coal and gas outburst, rock burst, water inrush and roof fall are proposed. The characteristics of the time domain and frequency domain of each accident sound are different from the characteristics of other sounds, and the sound can be monitored in real time by mine explosion-proof sound pickup equipment and system. Therefore, accidents can be sensed and alarmed through the intelligent analysis of the sound and the analysis of the characteristic parameters of the sound frequency, amplitude and short-term energy. By monitoring and analyzing the sound intensity and other characteristics of different monitoring locations, the sequence of occurrence and the damage sequence of explosion-proof sound pickup equipment, the accident location is able to be determined. Based on the characteristics of each accident, the accident identification method of multi-information fusion analysis is proposed to reduce the sound interference of coal fall from the working face, blasting operations, coal mining equipment, excavation equipment, transportation and lifting equipment, power supply equipment, emulsion pumps, water pumps and local ventilators. The paper discusses the advantages and disadvantages of different sound pickup equipment and proposes that the microphone arrays should be used for mine sound pickup equipment. Furthermore, the paper proposes a sound recognition classifier applicable to coal mine extraordinary accidents.

The standard stipulates product classification, general requirements, environmental conditions, power supply, system design requirements, basic functions, software functions, main technical indexes, transmission performance, power fluctuation adaptability, working stability, anti-interference ability and explosion-proof performance of coal mine safety monitoring system. The standard is applicable to coal mine safety monitoring system used in coal mine.

In order to further play role of coal mine safety monitoring system in gas control, AQ 1029-2007 Use Management Specification of Coal Mine Safety Monitoring System and Testing Instrument should be amended. The main contents of proposed amendments include: adding wind direction sensor and dust sensor; mine directors in underground should carry wireless portable methane alarm detector or wireless digital methane detect and alarm head lamp with wireless transmission function; protection grade of sensor should be not less than IP65; coal and gas outburst mines should use full range or high and low concentration methane sensor; coal mine safety monitoring system should be networked, and upload real-time monitoring data to superior; the system can transmit information by cable or optical cable; backbone cable should be divided from different shaft or from different positions with some distance in a shaft into underground; safety monitoring system cannot share the same optical fiber with image monitoring system; safety monitoring equipment should be regularly adjusted and tested 1 time per month at least; adjustment period of carrier catalytic methane sensor, wireless portable methane alarm detector and wireless methane detect and alarm head lamp should be increased from 10 days to 15 days, and the sensor should be adjusted in setting location; methane electric blocking and wind power blocking function should be tested at least 1 time per 15 days, and equipment that may cause local ventilator power outage should be tested 1 time per 6 months; dual host computer hot-backup is needed, and switch time from the host to the backup host should be not more than 40 s; scheduling staff on duty should power off and order related personnel to evacuate after receiving alarm, power outage and abnormal feed information.

In order to further play role of coal mine safety monitoring system in gas control, AQ 6201-2006 General Technical Requirements of Coal Mine Safety Monitoring System should be amended. The main contents of proposed amendments include: increasing alarm and power-off locking function of coal and gas outburst, increasing wind direction sensor; allowing the use of optical fiber cable transmission in the system; enhancing sensor protection grade to IP65; dual host computer hot-backup and automatic switch are needed and lightning protection of underground power source is not needed; reducing transmission processing error; error rate of analog input, analog output and cumulative input transmission processing is not more than 0.5%; shortening the maximum inspection cycle of the system, which is not more than 10 s; prolonging record storage time and shortening information missing time; real-time monitoring value of methane and other important monitoring points should be kept for more than 3 months, analog value statistics and records should be kept for more than 2 years; when a system failure occurs, time length of losing above information should be not more than 40 s; shortening response time of extracting picture, response time of extracting 85% of the whole picture is less than 1 s, and response time of extracting the other pictures is less than 2 s; reducing bit error rate, which should not be greater than 10-9; increasing transmission distance from substation to sensor and power supply distance from intrinsically safe power source to substation, the transmission distance from substation to sensor and actuator and the power supply distance should be more than 2 km, or 3 km, or 6 km; shortening switch time of two computers, the time from the host fault to the backup host into normal working should be not more than 40 s; increasing working time of backup power source, when grid is blackout, the backup power source should be able to ensure that the system continuous monitoring time is not less than 3 h; reducing immunity test level, the immunity levels of electrostatic discharge, RF electromagnetic field radiation, electrical transient bursts and surge are the second level; canceling requirements of reliability; monitoring equipments used in underground coal mine must be explosion-proof.

Colliery gas accidents in recent 10 years were analyzed, and numbers of accidents and deaths accounted for 62.3% and 66.5% respectively. The placement methods of coal and gas outburst alarm sensors of methane, wind speed, wind direction were put forward. Coal and gas outburst alarm methods were proposed based on coal mine safety monitoring system, namely monitoring and analyzing methane, wind direction, wind speed and sensor fault, specifically, sending out sound and light alarm signal, cutting off all power supply for intrinsically safe electrical equipment in coal mine, and pulling out of coal mine workers in the following cases: wind speed is normal and methane concentration increases rapidly or exceeds alarm concentration; wind direction reverses in intake airway and methane concentration increases rapidly or exceeds alarm concentration; and methane concentrations in intake airway increases quickly or exceeds alarm concentration.