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Ultra-wide band (UWB) radar can penetrate non-magnetic media such as coal and rock to detect life information of personnel after collapse. Due to the complex mining environment, UWB radar loaded with vital sign signals is prone to interference from environmental noise and clutter signals. It is difficult to recognize human subject information. This paper introduces the principle of UWB radar life detection system and its application in mine rescue. This paper summarizes the current research status of UWB radar life information recognition from three aspects: UWB radar life information extraction, dynamic and static human object recognition, and life quantification. This paper points out the current issues with the application of UWB radar life detection technology in the field of mine rescue. ① There is limited research on filtering methods for non-stationary signals and environmental noise in underground collapse environments. ② The extraction and representation methods for posture, behavior, life status, and other information of moving (or micro moving) objects need to be improved. The human life information recognition model is not yet perfect and the feature correlation between models is low. ③ There is a lack of solutions to the 'overlapping' problem caused by multiple objects. This paper proposes the prospects for the research direction of UWB radar life information recognition for mine rescue. ① It is suggested to continuously optimize noise and clutter adaptive filtering methods for multiple types of mine disaster environments. ② It is suggested to construct a human life information recognition model suitable for the field of mine rescue. ③ It is suggested to further improve the quantification capability of multi-object after mine shelter. ④ It is suggested to conduct depth exploration of the method for determining the optimal detection frequency band for UWB radar.

Deep well rescue technology refers to the key technologies involved in various aspects of rescuing trapped personnel during the process of deep well accident rescue. It mainly includes environmental detection technology, life detection technology, deep well rapid demolition technology, emergency communication network construction technology, and other auxiliary technologies to ensure the smooth progress of deep well accident rescue. Deep well rescue equipment refers to necessary hardware equipment and software platforms during the implementation of deep well rescue technology. Studying deep well rescue technology and equipment is crucial for ensuring the safety of trapped personnel and reducing accident losses. The current research status of deep well rescue equipment and key technologies is analyzed. It is pointed out that existing rescue technologies and equipment cannot fully meet the complex and changing environmental requirements. There are problems such as insufficient research on the universality and specificity of rescue equipment, the need to improve the intelligence level of rescue equipment, difficulty in meeting the needs of complex rescue environments with network collaboration capabilities, and insufficient innovation research on rescue equipment. In order to solve the above issues, the development trend of deep well rescue equipment and technology is discussed. ① Deep well rescue equipment should be divided into specialized and universal categories based on different rescue scenarios. A single equipment should develop towards multifunctionality, high reliability, and high mobility. ② Rescue equipment is intelligent, precise, and self decision-making, achieving a rescue mode of intelligent equipment as the main focus and personnel as the auxiliary. ③ It is suggested to build a rapid networking, multi-mode networking, and integrated rescue network platform. ④ Although TDLAS integration does not currently meet rescue standards, its high resolution, high sensitivity, and integrability will play an important role in the future, achieving high integration, lightweight, and efficiency of environmental monitoring equipment.

As a device for timely rescue after disasters, life detectors play an irreplaceable role in locating, exploring, and searching for living organisms. This paper analyzes the working principles, technical features, usage scenarios, advantages and disadvantages of the currently used life detectors. The detectors include radar life detectors, audio life detectors, infrared life detectors, and other types of life detectors. Combined with practical applications, this paper points out the problems of the above life detectors. ① The detection technology is single and the comprehensive integration is low. ② The detection methods are traditional and equipment intelligence is insufficient. ③ The parts of the detector are not standardized, making equipment maintenance difficult. ④ Some life detectors have a relatively large structure and are inconvenient to carry, which affects rescue efficiency. In response to the existing shortcomings and problems, the development trends of life detectors are proposed. ① It is suggested to improve the integration level of life detectors. It is suggested to design life detection devices that use multi-source fusion to collect information, and use multiple information sources to obtain and detect life information. ② It is suggested to improve the intelligence level of life detectors, give them partial autonomy in decision-making, and reduce errors in life detection caused by improper operation by operators. ③ It is suggested to design modular life detectors and develop relevant standard procedures to standardize the components of the same type of life detector. It will reduce the difficulty of repair and maintenance of life detectors. ④ It is suggested to improve the circuit board design precision of the life detector, fully utilize spatial structure, reduce volume and improve portability without reducing the functionality of the life detector.

The ultra wideband (UWB) radar detection technology can achieve mine human target detection for drilling rescue. However, UWB electromagnetic waves are susceptible to the complex environment of catastrophic mines. The UWB radar echo signals are susceptible to the background clutter and environmental noise of catastrophic mines. It is difficult to achieve precise detection of human targets in catastrophic mines. In order to solve the above problems, the underground target detection scenarios and human target detection principles based on UWB radar are introduced. The research status of UWB electromagnetic wave characteristics and UWB echo noise filtering methods are analyzed. The existing problems are summarized as following points. ① The propagation characteristics of UWB electromagnetic waves in the complex environment of catastrophic mines require in-depth research. ② The reason for the generation of background clutter is not yet clear. There is limited research on the filtering technology of background clutter and environmental noise in catastrophic mines. ③ The UWB radar human target detection technology for drilling rescue still needs to be improved. In response to the shortcomings of existing technologies, the development trend of UWB radar underground human target detection technology for drilling rescue is prospected. ① It is suggested to do in-depth research on the sensitivity of key characterization parameters of UWB electromagnetic wave penetration transmission to complex underground environmental characteristics. ② It is suggested to construct methods for filtering background clutter and environmental noise suitable for catastrophic mines. ③ It is suggested to deeply optimize UWB radar human target detection technology for drilling rescue.

Obtaining the position of underground trapped personnel quickly and precisely is a key issue for life information detection in the early stage of borehole rescue. In the process of vertical drilling and rescue, due to the collapse of the roadway in the detection area or the displacement of the final hole position, it is impossible to obtain the position of the trapped personnel quickly and accurately. It delays the golden time of rescue and affects the safety of personnel. Through conducting a UWB radar wave transmission attenuation study, a rescue plan can be quickly formulated for on-site rescue commanders. This paper analyzes the current situation and demand of UWB radar wave application in mine borehold rescue. Combined with the background of mine borehold rescue, it is pointed out the attenuation law of UWB radar wave transmission. The study analyzes the influence of the characteristic parameters of the medium on the attenuation of radar wave transmission from the perspective of anisotropy of the medium. The influence of dielectric parameters on radar wave transmission attenuation is analyzed from four aspects: dielectric constant, conductivity, magnetic permeability and spatiotemporal variation. The influence of radar characteristic parameters on radar wave transmission attenuation is analyzed from two aspects: radar frequency and polarization. Based on the above analysis, it is pointed out that there are few studies on the simultaneous penetration of UWB radar waves through anisotropic media such as coal and rock masses and the mechanism of media propagation and attenuation. There are few theories and experiments on UWB radar wave transmission attenuation in complex and changeable underground or simulating disaster environments. And there are few summaries of relevant laws. The mapping relationship database between key parameters and influencing factors of UWB radar waves is not yet complete. The key technologies to be studied in the future are given as follows. It is suggested to conduct research on anisotropic media such as coal and rock masses at both macro and micro levels. It is suggested to establish an experimental simulation system for radar wave transmission attenuation under catastrophic environmental conditions. It is suggested to add research on UWB radar signal propagation characteristics and channel modeling numerical simulation in unstructured environments after disasters.

This paper proposes an idea of pouring gasification ash into the underground goaf as a grouting fire prevention and extinguishing material. In order to effectively solve the problem that the gasification ash slurry of coal-based oil tends to block the pipeline in the process of grouting, the influence of three suspension agents such as xanthan gum, carboxymethyl cellulose(CMC) and sodium soil on the suspension rate and fluidity of gasification ash slurry was studied through a series of experiments. The results showed that with the increase of the amount of suspension agent, the suspension rate of slurry increased gradually, and its fluidity decreased gradually. More specifically, when the addition amount of xanthan gum, CMC and sodium-soil was 0.25%, 1.5%and 3%, respectively, the suspension rate reached the maximum with 81.82%, 72.73% and 53.24%, respectively. Among the three suspending agents, xanthan gum has the best suspending effect on gasification ash, followed by CMC and sodium-soil. The fluidity experiment showed that the fluidity of the slurry was the worst with adding xanthan gum to the slurry, which is not beneficial for the pipeline transportation of the slurry. While sodium-clay is added to slurry, the fluidity of the slurry is the best. But it is prone to water-cement separation and blockage of the pipe. Hence, considering suspension rate and flow, CMC was selected as suspension agent.

The existing mine moving target positioning system has the problems of serious attenuation of underground wireless signal transmission, large non-line-of-sight error, complex underground electromagnetic environment, wide sensing range of dynamic and static targets, strong linkage of multi-system information fusion, etc. At present, the research on mine moving target precise positioning technology and optimization method does not comprehensively analyze the characteristics and technical requirements of the moving target accurate positioning service. It lacks a comprehensive comparison between the mainstream and emerging positioning technologies. In order to solve the above problems, the advantages and disadvantages of the common signal transmission technology and the positioning and ranging method applied in the mine moving target precise positioning system are analyzed. The radio positioning technology is pointed out to be a more suitable and feasible mine moving target precise positioning technology. This paper analyzes the research status and existing problems of the optimization method of the mine moving target precise positioning in China from four aspects: signal anti-collision technology, error elimination method, positioning result optimization method and fusion positioning technology. ① The comprehensiveness of the signal anti-collision algorithm still needs to be improved. ② The efficiency of ranging error control means needs to be improved. ③ The application of the fusion positioning method in the production site is not yet mature. ④ The auxiliary role of the system in emergency rescue is not fully played. In view of the shortcomings of the existing technology, the development trend of the mine moving target precise positioning technology is proposed: ① It is suggested to study the signal collision mechanism and post-conflict recovery mechanism in dynamic environment, and design a comprehensive signal anti-collision scheme. ② It is suggested to research precise, efficient and economical ranging error control scheme to save communication costs. ③ It is suggested to study dynamic positioning scheme design with deep integration of multiple positioning methods to improve the reliability, flexibility and applicability of the system. ④ It is suggested to study the multi-system linkage scheme and the emergency communication and positioning recovery mechanism in extreme cases, and give full play to the role of the system in emergency rescue.

Aiming at the problems and technical difficulties in the vertical rescue process of mines, such as single information collection and low degree of visualization, a set of technology methods such as multi-media collection, fusion of multiple information, wired and wireless transmission, and intrinsically safe control of communication circuits have been developed. The life information detection system of the long distance borehole has been successfully applied in the collapse accident of Wanzhuang gypsum mine in Pingyi County, Linyi City, Shandong Province and the explosion accident of Hushan gold mine in Qixia City, Shandong Province. Field rescue application results show that: the life information detector has strong reliability, stable information transmission, with video/audio and underground environmental parameters collection and synchronous transmission functions, real-time feedback of detected multimedia information to the ground rescue command, and the information is automatically saved to the terminal equipment to provide reference materials for formulating scientific rescue plans and subsequent accident summary.

In view of the high cost of the gel fire-fighting technology in the field and the difficulty of large-scale use, the relatively cheap coal chemical solid waste gasification ash is used as the base material and hydroxypropyl methylcellulose gelling agent (HPMC) is added. Later, a new type of gasification ash gel material was prepared. Meanwhile, taking lignite as the research object, the coal spontaneous combustion retardant properties of CaCl2 inhibitor and gasification ash gel were compared and analyzed by temperature-programmed gas chromatography combined experiment and FTIR Fourier transform spectrometer. The results show that with the increase of coal temperature, the release concentrations of CO and C2H4 in the coal samples with the addition of CaCl2 inhibitor and gasification ash gel are significantly lower than those in the raw coal, and the CO inhibition rates reach 46% and 67.5% at 110 ℃, respectively; gasification ash gel can increase the oxygen activation energy of coal by 25.2% in the temperature range of 30 ℃ to 200 ℃; the gasification ash gel can reduce the content of C-O, C=C functional group, effectively inhibit the free radical chain reaction, and its inhibition effect is better.

In the mine rescue process, the current video and audio based borehole life information identification technology has the problems of video obstacle failure and fast speed of sound wave attenuation. In order to solve the above problems, the ultra-wide band (UWB) radar technology that can penetrate coal rock bodies, brick walls and other obstacles for non-contact measurement and realize life information identification is studied. The application status and existing problems of UWB radar technology in mine borehole rescue are analyzed from three aspects, including UWB electromagnetic wave transmission attenuation characteristics, clutter filtering and optimization, and the target life identification method. ① UWB electromagnetic waves can detect and locate the life information of people behind obstacles. Its attenuation is related to the electric field, magnetic field strength, frequency and medium. However, the current research on the attenuation characteristics of UWB electromagnetic wave transmission lacks the research on the law relationship between various coal and rock masses and UWB electromagnetic wave transmission attenuation at different temperatures, detection frequencies, and metamorphic degrees. There are few researches on the relationship between UWB electromagnetic wave frequency, incident angle, polarization form and other key parameters and change characteristics and UWB electromagnetic wave attenuation. ② The methods such as empirical mode decomposition method and MUSIC method can filter the clutter in UWB electromagnetic waves. But the methods lack accurate extraction and scientific representation of effective wave characteristics and information after clutter filtering, which makes it difficult to improve the speed and accuracy of life information characteristics extraction and identification. ③ UWB electromagnetic waves can capture the life signs of multiple target people behind obstacles, such as breathing or heartbeat. The use of multiple radar observation points can improve the accuracy of life information detection in a low signal-to-noise ratio environment. However, the current research lacks systematic identification and quantitative analysis of breathing, heartbeat, chest undulation, body temperature in multiple directions and from multiple angles. And the current research lacks an optimized method for life information identification models. In order to solve the existing problems, the research directions of UWB radar technology for borehole rescue application are pointed out as follows. ① It is proposed to study the influence of the properties of coal and rock masses and electromagnetic wave related parameters on the transmission attenuation of UWB electromagnetic wave in coal and rock masses under different conditions. The law of transmission attenuation is obtained. ② It is suggested to study on clutter filtering optimization and echo characteristic extraction algorithms suitable for mine environment, and use the effective characteristics in the echo to establish a learning sample database. ③ It is proposed to construct the personnel life information identification model applicable to the mine environment, and continuously optimize the model with the sample database to improve the accuracy and speed of life information identification.

Most of the existing research on the influencing factors of coal electrical parameters are carried out under fixed frequency or low frequency and high temperature conditions. There is a lack of research on the influencing factors of coal electrical parameters under ultra-wideband frequency and normal temperature conditions. Therefore, there are certain limitations in the research on the influencing factors of coal electrical parameters. To address this problem, in order to study the influence of coal electrical parameters on the selection of ultra-wideband radar wave mine detection frequency band under different conditions, the Concept-80 ultra-wideband dielectric spectrum test system is applied. The system is set to detect the relative permittivity, electrical conductivity and loss angle tangent values of coals with different metamorphic degrees (lignite, long-flame coal and lean coal) at 0-80 ℃ and 500-1 000 MHz detection frequency and analyze their variation laws. The analysis results show that the relative permittivity of coal increases with the increase of coal metamorphic degrees, and the electrical conductivity and loss angle tangent values of coals decrease with the increase of coal metamorphic degrees. The relative permittivity of coal samples with different metamorphic degrees decreases, then increases and decreases again with the increase of detection frequency, and the relative permittivity is positively correlated with temperature. The electrical conductivity is positively correlated with both detection frequency and temperature. The loss angle tangent value is positively correlated with temperature. However, the detection frequency does not reflect the variation of loss angle tangent value well. Based on the variation law of three electrical parameters at different temperatures and detection frequencies, and the comprehensive comparison of influence of three electrical parameters on the transmission of ultra-wideband radar waves in coal, it is pointed out that the frequency of 550-650 MHz performs best when using 500-1 000 MHz ultra-wideband radar waves to penetrate the coal body for detection at 0-80 ℃, and the detection frequency should decrease as the temperature increases. The conclusion of this study can provide a reference for the selection of ultra-wideband radar wave mine detection frequency band under different conditions.

The research status of the key technologies of multi-rotor detection unmanned aerial vehicles(UAVs) in mine dangerous areas at home and abroad is reviewed from three aspects: autonomous positioning and navigation technology, autonomous obstacle avoidance technology and multi-sensor information fusion technology. Autonomous positioning and navigation technology enables robots to move autonomously in unknown environments without human intervention. Combined navigation technology, 3D environment map building technology, deeply optimized trajectory planning algorithms and simultaneous positioning and map building technology based on semantic and deep learning are suitable for mine conditions with complex and unstable mine environmental conditions where disaster information evolving over time.The obstacle avoidance method based on multi-sensor information fusion can ensure that the multi-rotor detection UAV can perceive obstacle information to the maximum extent under different environmental conditions. The sensor fusion architecture based on autonomous positioning and obstacle avoidance technology need to adopt a distributed structure to make the mine multi-rotor detection UAV system have high reliability and fault tolerance.The problems of multi-rotor detection UVAs are analyzed from both software and hardware aspects. The problems include that the universality of the fusion model and algorithm cannot be guaranteed,the fusion system's fault tolerance or robustness needs to be improved, the lack of processing hardware to adapt to a variety of complex fusion algorithms, and the low degree of integration, high power consumption and large size of multi-sensor.The development trend of key technologies of multi-rotor detection UAVs in mine dangerous areas is prospected. ① Fusion algorithm optimization: it is crucial to maximize the optimization of fusion algorithm, improve system reliability and stability and ensure stable and efficient data processing. ② Application of artificial intelligence technology: improving the deep learning ability of multi-rotor detection UAVs and expanding the detection range of mine dangerous areas by applying intelligent technologies such as machine learning and adaptive technology. ③ Development of processing hardware that can adapt to multiple complex fusion algorithms: the conditions of mine dangerous area are extremely complex, and it is difficult to achieve simultaneous collection and processing of underground multi-source information without the processing hardware that can adapt to the deep fusion of multiple algorithms. Therefore, the information processing ability of multi-rotor detection UAVs can be improved by developing processing hardware with strong adaptability. ④ Development of convenient hardware fusion system: developing a fusion system based on the deep integration of multiple sensors could further enhance the detection capabilities of multi-rotor detection UAVs.

As one of the five major disasters in coal mine production, coal spontaneous combustion severely restricts the safety, efficiency and eco-friendliness in the mining process. Due to the diversified characteristics of theoretical methods for the prevention mechanism and prevention technology of coal spontaneous combustion fire disaster, this paper analyzes the difficulties for the prevention and control of coal fire disaster. The advantages and disadvantages of prediction methods and disaster prevention technology for the existing coal seam fire are discussed. The development prospects of coal spontaneous combustion fire prevention technology are prospected. On this basis, the key direction of research on coal seam fire prevention in China in future includes: the formation, evolution and inhibition mechanism of coal spontaneous combustion; fine division of coal spontaneous combustion stage; dynamic monitoring and intelligent early warning of coal spontaneous combustion; active, grading and coordinated prevention and control of coal spontaneous combustion.

By analyzing research status of power system, positioning system, environmental monitoring system and communication system of mine detection unmanned aerial vehicle (UAV) at home and abroad, the problems of mine detection UAV were pointed out, such as insufficient cruising power, poor positioning accuracy, weak information perception ability and poor information data transmission performance. For the above problems, the development trends of mine detection UAV were prospected: ① Application of new energy or new power supply technology, the whole power management system is optimized in a more efficient and reasonable way to detect power consumption of electric equipment in real time, improve power efficiency and enhance endurance time of detection UAV, and meet explosion-proof performance. ② Development of UAV cluster system based on collaborative navigation search, the hybrid UAV cluster control structure overcomes the shortcomings of poor communication reliability and low search efficiency in distributed structure and solves the problems of weak robustness and autonomy in centralized structure; the system can improve the positioning accuracy and shorten the rescue time through mathematical optimization algorithm for information derivation and multi-UAV collaborative information fusion. ③ Design of UAV monitoring platform based on multi-sensor fusion technology, the multi-sensor information coordination and mutual fusion based on BP neural network algorithm can improve the UAV's perception ability to underground environment. ④ Application of multi-UAV chain wireless Mesh networking mode, when multi-UAVs search in underground environment, the information collected by each UAV is local area information， all UAVs conduct information fusion and resource complementarity to update the environmental information status in real time through the chain wireless Mesh networking mode, so as to improve reliability of detection and rescue efficiency.

The research status of intelligent monitoring and early warning technology in coal mine in China was summarized from the aspects of Internet of things, big data, cloud computing and artificial intelligence.According to practical application of intelligent monitoring technology in coal mine, the problems of intelligent monitoring and early warning in coal mine was points out, including poor reliability of precursory information collection of underground coal mine monitoring equipment, insufficient depth of cloud platform integrated application and fusion, weak database security, and immature application of artificial intelligence technology in coal mine monitoring.The development trend of intelligent monitoring and early warning technology in coal mine was prospected: the application of graphene/graphene oxide optical fiber sensors in intelligent monitoring system of coal mine can realize multi-source information perception and improve the reliability of precursory information collection; studying multi-technology deep cross fusion to explore deep value of monitoring data; constructing coal mine monitoring database based on block chain technology, ensuring that the database cannot be tampered and has good read and write performance; developing intelligent safety monitoring and warning system with adaptive and deep learning, realizing mine automatic monitoring and intelligent early warning.

Based on analysis of principle and characteristics of traditional water inrush source, fire and gas concentration detection technologies of coal mine rescue robot, water inrush source detection method of coal mine rescue robot based on wireless ad-hoc network, fire detection method of coal mine rescue robot based on big data and gas concentration detection method of coal mine rescue robot based on multi-source information fusion were proposed, which could effectively improve accuracy of water inrush water, fire and gas concentration detection of coal mine rescue robot. It was pointed out that disaster environment detection technology of coal mine rescue robot would deeply integrate modern information technologies such as cloud computing, artificial intelligence and Internet of things, so as to comprehensively improve reliability of disaster environment detection results of coal mine rescue robot.

In view of problems of short endurance time, long period of data collection, low accuracy of infrared thermal image and slow data transmission and processing of existing technologies of unmanned aerial vehicle(UAV) monitoring of coalfield fire, UAV monitoring technologies based on single/cluster flight, infrared and visible light dual vision monitoring technology, data transmission and processing technology based on 4G network were studied. Multi-station multi-machine cluster flight mode of UAV is designed, and rapid monitoring of large-area coalfield area is realized through route planning and independent control. Data acquisition is carried out by infrared dual-view thermal imager, the UAV triggers infrared dual-view thermal imager to capture infrared thermal images and visible light images when hovering at an equally spaced waypoint.4G network is used as signal transmission channel, and data acquisition front end and data processing software are synergistically used to realize synchronization of data collection, transmission and processing. Field application results show that two UAVs collect 254 infrared thermal images and 254 visible light images, the data acquisition and image pre-processing takes 150 minutes, and the image synthesis takes 10 hours, monitoring time is greatly shortened compared with existing technology; Coincidence degree of temperature displayed by infrared thermal image and the field temperature test result is above 90%, indicating that using UAV for coalfield fire monitoring is effective and feasible.

The paper introduced general situation of explosion-proof technology of coal mine rescue robot, and summarized the research status and application of explosion-proof technology of coal mine rescue robot at home and abroad, and pointed out some progress of explosion-proof technology for coal mine rescue robot, especially in explosion-proof motor, explosion-proof shell and power supply. However, there are still problems in explosion-proof material application technology, energy power technology, intrinsic safety control technology, fault diagnosis and fault-tolerant control technology, it needs to be constantly improved in the aspects of processing materials lightweight, power supply efficiency, intrinsic safety of explosion protection technology, intelligent control system, so as to ensure the explosion-proof technology of each component of coal mine rescue robot is more mature.

In view of problems of poor adaptability, communication ability and maneuverability of current mine robots, a mine rescue robot group was designed. The robot group mainly includes a communication robot, a search and rescue robot, an auxiliary rescue robot, and a data processing center. The communication robot uses UWB radar for life detection to find out specific location of trapped person, and at the same time guarantees information transmission during rescue process through built-in relay device. The search and rescue robot walks according to the real-time path and feedback audio, video, and underground environment information, and acts as a communication device after finding the trapped person, thus constructs a communication channel between the rescuer and the trapped person. The auxiliary rescue robot includes a wrecking robot which is responsible for getting through the rescue route and a material transport robot which is responsible for delivering rescue items to the trapped people. The data processing center plans search and rescue route of rescue robot through GIS according to position information of the trapped person, and correct the path according to underground real-time information. All kinds of robots in the robot group cooperate with each other, complement each other's functions, and unify the information, which can effectively reduce secondary damage caused by unclear environment after the disaster and improve rescue efficiency.

The research status and application of power system, explosion-proof design, multi-parameter monitoring and communication system of coal mine rescue robots at home and abroad were introduced, and the existing problems of coal mine rescue robots, such as limited cruising ability, short walking control distance, heavy weight of explosion-proof materials, poor reliability of information processing and transmission were pointed out. The development trend of coal mine rescue robots was prospected, that is, research and development of new energy batteries suitable for coal mine is one of the development trends of power supply of coal mine rescue robot, research and development of intelligent robots with autonomous walking, positioning and path planning is the development trend of coal mine rescue robots in the future, lightweight explosion-proof materials, intelligent integration of multi-source information, wireless and wired communication mode will also be the direction of intelligent development of coal mine rescue robots.

Research status of coalfield fire monitoring technologies was reviewed including electromagnetic detection method, resistivity method, radio wave method, geological radar method, gas measurement method, isotope radon measurement method, temperature method, remote sensing method and so on. Advantages and disadvantages of each technology were compared. It was pointed out that there were some questions existed in coalfield fire monitoring technologies at current such as lots of environmental factor limits, high cost, large technical limits and so on. Prospect of coalfield fire monitoring technology was taken out. It was pointed out that low altitude remote sensing technology of unmanned aerial vehicle equipped with an infrared thermal imager was development direction of coalfield fire monitoring technology. Moreover, development ideas were proposed which took high efficiency, intelligence and integration as leading role.

The paper expounded principles of mine drilling rescue communication technology, emphatically introduced research progress at home and abroad of drilling rescue communication technology, including drilling rescue detection technology, mine rescue command system and visualization technology, high-speed transmission and exchange technology of drilling rescue, pointed out problems need to be solved of mine drilling rescue communication technology and its development tendency: each function and composition of drilling rescue communication system should be independent and organic unification, so as to guarantee normal use of other functions of the system in upgrade process;drilling rescue communication technology should have higher accuracy on links of sound and video image acquisition, environmental monitoring of disaster scene, communication and storage; the drilling rescue communication system should have functions of self-check and recovery through further improving of reliability of data communication system, so as to provide effective reference for establishment of mine rescue plan; application software matched with rescue communication equipments was perfected to ensure that rescue information is real-time interaction transmission with vivid presence to facilitate commanders to do subsequent decisions; error and error judgement and early warning technology of data acquisition system was researched to ensure accurate of rescue information and improve rescue efficiency and success.