Mine Rescue Research Articles

Identification of mine rescue equipment reduction gears technical condition

The article presents the reasons for adopting intelligent service of mine belt conveyer drives concerning evaluation of their technical condition based on the diagnostic techniques instead of regular preventative maintenance. The article reveals the diagnostic results of belt conveyer drive reduction gears condition taking into account the parameters of lubricating oil, vibration and temperature. Usage of a complex approach to evaluate technical conditions allows reliability of the forecast to be improved, which makes it possible not only to prevent accidental breakdowns and eliminate unscheduled downtime, but also to bring sufficient economic benefits through reduction of the term and scope of work during overhauls.

Design of a new type of mine rescue relay cabin

This paper presents the design of an innovative mine emergency rescue relay cabin, and investigates a detailed comparison of existing shelter facilities, their function, service object, structures, size, and system components with the newly designed mine emergency rescue relay cabin. Air-tightness test indicated a test chamber relief rate of 26Pa/min, which meets the design requirements. Furthermore, respirator replacement test showed an average time of 73.7s to replace a respirator. The air cover air supply test indicated an air supply rate of 220L/min, which is sufficient for the staff replacing the respirator in the emergency rescue relay cabin. The total air supply volume is 9680L, which can be supplied via two compressed air cylinders of 40L, pressurized to15MPa.

Numerical simulation on structural safety and dynamic response of coal mine rescue ball with gas explosion load using Arbitrary Lagrangian-Eulerian (ALE) algorithm

Coal mine rescue devices, which can supply miners underground with fundamental shelters after gas explosion, are essential for safety production of coal mines. In this paper, a novel and composite structure-rescue antiknock ball for coal mine rescue is designed. Further, the structural safety and dynamic response under gas explosion of the antiknock ball is investigated by ALE algorithm. To achieve this goal, the ALE finite element method is described in dynamic form, and governing equations and the finite element expressions of the ALE algorithm are derived. 3 balls with different structures are designed and dynamic response analysis has been conducted in a semi-closed tunnel with explosive load of pre-mixed gas/air mixture by using ALE algorithm based on explicit nonlinear dynamic program LS-DYNA. Displacement field, stress field and energy transmission laws are analyzed and compared via theoretical calculations. Results show that the cabin door, emergency door and spherical shell are important components of the rescue ball. The 3# composite ball is the optimization structure that can delay the shock effect of the gas explosion load on a coal mine rescue system; the simulation results can provide reference data for coal mine rescue system design.

A Novel Design of Rescue Capsule considering the Pressure Characteristics and Thermal Dynamic Response with Thermomechanical Coupling Action Subjected to Gas Explosion Load

To ensure the structural safety and reliability of coal mine rescue capsule in disastrous surroundings after gas explosion, in this paper, the thermomechanical coupling effect on a certain structure subjected to gas explosion was analyzed, and then a novel rescue capsule with a combination of radius and square features was designed according to the underground surroundings and relevant regulations on mine rescue devices. Foremost, the coupling mechanism of thermal-fluid-solid interaction between gas explosion shock wave and rescue capsule and the thermal dynamic response of the capsule subjected to explosion load of gas/air mixture was investigated and revealed by employing LS-DYNA. The variation laws and characteristics of stress field, displacement field, and temperature field of the capsule were analyzed based on the simulation results. Results show that the structural safety, tightness, and reliability of the capsule meet the requirements of the national safety regulations. The design method presented in this work provides a new thought for design of coal mine rescue capsule.

STUDY ON THE BEHAVIOUR OF MINE RESCUE BRIGADESMEN EXPOSED TO HIGH TEMPERATURE AND HUMIDITY IN THE TRAINING FACILITY

Intervention and rescue activity in special conditions may be conducted only by trained and authorized personnel using individual protective breathing equipment. While working with the insulating respiratory device, there are a number of factors that make work stressful. As a rule, those working under protection of the insulating respiratory devices, besides carrying on their back a device weighing 14-18 kg, are also subject to great difficulty, in terms of securing their own safety, saving lives, quick-acting under heavy microclimate conditions (high heat and humidity). For interventions demanding predominantly physical effort, in high temperature and humidity environments, where work processes involve large muscle groups, changes in physiological indicators, during or immediately after effort, have been observed, especially in the cardiovascular system and respiratory system. In this respect, the paper presents a research on changes in physiological parameters (pulse and blood oxygen saturation) of intervention and rescue personnel in situations where they have to intervene in high temperature and humidity environments. To that effect, several teams of mine rescue brigadesmen were monitored throughout their training within the National Institute for Research and Development in Mine Safety and Protection to Explosion INSEMEX Petrosani training facility, which may generate the most unfavourable conditions that can be encountered in various emergency situations.

Explosion risk assessment model for underground mine atmosphere

In the coal mining industry, explosions or mine fires present the most hazardous safety threats for coal miners or mine rescue members. Hence, the determination of the mine atmosphere explosibility and its evolution are critical for the success of mine rescues or controlling the severity of a mine accident. However, although there are numbers of methods which can be used to identify the explosibility, none of them could well indicate the change to the explosion risk time evolution. The reason is that the underground sealed atmospheric compositions are so complicated and their dynamical changes are also affected by various influence factors. There is no one method that could well handle all such considerations. Therefore, accurately knowing the mine atmospheric status is still a complicated problem for mining engineers. Method of analyzing the explosion safety margin for an underground sealed atmosphere is urgently desired. This article is going to propose a series of theoretical explosion risk assessment models to fully analyze the evolution of explosion risk in an underground mine atmosphere. Models are based on characteristics of the Coward explosibility diagram with combining mathematical analyzing approaches to address following problems: (1) for an “not-explosive” atmosphere, judging the evolution of explosion risk and estimating the change-of-state time span from “not-explosive” to “explosive” and (2) for an “explosive” atmosphere, estimating the “critical” time span of moving out of explosive zone and stating the best risk mitigation strategy. Such research efforts could not only help mine operators understand the explosibility risk of a sealed mine atmosphere but also provide a useful tool to wisely control explosive atmosphere away from any dangers. In order to demonstrate research findings, case studies for derived models are shown and are also used to instruct readers how to apply them. The results provide useful information for effectively controlling an explosive underground sealed atmosphere.

Transient electromagnetic fields of a buried horizontal magnetic dipole

Electromagnetic surveys using a vertical transmitter loop are common in land, marine, and airborne geophysical exploration. Most of these horizontal magnetic dipole (HMD) systems operate in the frequency domain, measuring the time derivative of the induced magnetic fields, and therefore a majority of studies have focused on this subset of field measurements. We examine the time-domain electromagnetic response of a HMD including the electric fields and corresponding smoke rings produced in a conductive half-space. Cases of a dipole at the surface and buried within the earth are considered. Results indicate that when the current in the transmitter is rapidly switched off, a single smoke ring is produced within the plane of the vertical transmitter loop, which is then distorted by the air-earth interface. In this situation, the circular smoke ring, which would normally diffuse symmetrically away from the source in a whole space, is approximately transformed into an ellipse, with a vertical major axis at an early time and a horizontal major axis at a late time. As measured from the location of the transmitter, the depth of investigation and lateral footprint of such a system increases with burial depth. It is also observed that the electric field measured in the direction of the magnetic dipole only contains a secondary response related to the charge accumulation on any horizontal conductivity boundaries because the primary field is always absent. This field component can be expressed analytically in terms of a static and time-varying field, the latter term adding spatial complexity to the total horizontal electric field at the earth surface at early times. Applications of this theoretical study include the design of time-domain induction-logging tools, crossborehole electromagnetic surveys, underground mine expansion work, mine rescue procedures, and novel marine electromagnetic experiments.

A novel explosion-proof walking system: Twin dual-motor drive tracked units for coal mine rescue robots

A new explosion-proof walking system was designed for the coal mine rescue robot (CMRR) by optimizing the mechanical structure and control algorithm. The mechanical structure innovation lies mainly in the dual-motor drive tracked unit used, which showed high dynamic performance compared with the conventional tracked unit. The control algorithm, developed based on decision trees and neural networking, facilitates autonomous switching between “Velocity-driven Mode” and “Torquedriven Mode”. To verify the feasibility and effectiveness of the control strategy, we built a self-designed test platform and used it to debug the control program; we then made a robot prototype and conducted further experiments on single-step, ramp, and rubble terrains. The results show that the proposed walking system has excellent dynamic performance and the control strategy is very efficient, suggesting that a robot with this type of explosion-proof walking system can be successfully applied in Chinese coal mines.

The Research and Development on CTJ10/96-6, the Strong Exhaust Driven by Air Pressure Sanitary Device of the Mine Rescue System

<p class="p1"><span class="s1">According to the technical specification requirements of the mine rescue system, CTJ10/96-6, we design a strong exhaust sanitary device driven by air pressure based on pneumatic control, which adopts a key control by mechanical button. It implements many functions, such as flushing and sealing the smell, measuring and strong exhaust by using mechanical and pneumatic transmission. It also meets the demand of design requirements for the safety and explosion-proof of the mine rescue system. </span></p>

The Research and Development on CTJ10/96-6, the Strong Exhaust Driven by Air Pressure Sanitary Device of the Mine Rescue System

<p class="p1"><span class="s1">According to the technical specification requirements of the mine rescue system, CTJ10/96-6, we design a strong exhaust sanitary device driven by air pressure based on pneumatic control, which adopts a key control by mechanical button. It implements many functions, such as flushing and sealing the smell, measuring and strong exhaust by using mechanical and pneumatic transmission. It also meets the demand of design requirements for the safety and explosion-proof of the mine rescue system. </span></p>

Exploring virtual mental practice in maintenance task training.

- This paper aims to contribute to a general understanding of mental practice by investigating the utility of and participant reaction to a virtual reality maintenance training among underground coal mine first responders. - Researchers at the National Institute for Occupational Safety and Health's Office of Mine Safety and Health Research (OMSHR) developed software to provide opportunities for mine rescue team members to learn to inspect, assemble and test their closed-circuit breathing apparatus and to practice those skills. In total, 31 mine rescue team members utilized OMSHR's BG 4 Benching Trainer software and provided feedback to the development team. After training, participants completed a brief post-training questionnaire, which included demographics, perceived training climate and general training evaluation items. - The results overall indicate a generally positive reaction to and high perceived utility of the BG 4 benching software. In addition, the perceived training climate appears to have an effect on the perceived utility of the mental practice virtual reality game, with benchmen from mines with more positive training climates reporting greater perceived efficacy in the training's ability to prepare trainees for real emergencies. - This paper helps to broaden current applications of mental practice and is one of the few empirical investigations into a non-rehabilitation virtual reality extension of mental practice. This paper also contributes to the growing literature advocating for greater usage of accurate and well-informed mental practice techniques, tools and methodologies, especially for occupational populations with limitations on exposure to hands-on training.

ANALYSIS OF THE EMERCOM STAFF’S PSYCHOLOGICAL STABILITY WITH STANDARDIZED MULTIFACTOR METHOD OF PERSONALITY RESEARCH (SMPR)

The paper demonstrates some results of researching the psychological stability of EMERCOM staff under stress. It features statistics on how different factors in emergency conditions influence EMERCOM staff of different age categories. It is noted that emotional lability depends on the experience and knowledge in a particular field and may decrease at the age of 40 – 50. Experimental data and multifaceted analysis have shown that mine rescue brigade 50-plusers can suffer serious psychological changes that have to be taken into consideration at job assignment.

Experimental investigation on Influencing Factors of air curtain systems barrier efficiency for mine refuge chamber

Air curtain systems for mine refuge chambers prevent harmful gases in the tunnel from entering the chambers, but their barrier efficiency is affected by their structural parameters, installation location and air flow angle as well as the size of the chamber door. Previous studies focused on air curtain systems installed on the top of the door frames of the mine rescue capsule, but no studies have investigated air curtain systems installed on two or three sides of the door frames. To improve the barrier efficiency of air curtain systems for refuge chambers, this study conducted an experimental investigation of the effects of the structural parameters, installation location, and air flow angle on the barrier efficiency for a constant size of the door frame. The results demonstrate that air curtain systems with air curtains installed on two sides of the door frame behind the door wall that ejected air parallel to the door frame provided a relatively good barrier effect; an air curtain system that used pipeline air curtains with a nozzle diameter of 1mm and a nozzle distance of 15mm exhibited a relatively good barrier effect and a barrier efficiency of 55–60%. In air curtain systems that use air knives, the air knife gap should be 0.1–0.2mm wide. Under reasonable parameters and installation conditions, there was no significant difference between the barrier effects against CO2 of air curtain systems that use pipeline air curtains and those that use air knives.

Factors influencing mine rescue team behaviors.

A focus group study of the first moments in an underground mine emergency response was conducted by the National Institute for Occupational Safety and Health (NIOSH), Office for Mine Safety and Health Research. Participants in the study included mine rescue team members, team trainers, mine officials, state mining personnel, and individual mine managers. A subset of the data consists of responses from participants with mine rescue backgrounds. These responses were noticeably different from those given by on-site emergency personnel who were at the mine and involved with decisions made during the first moments of an event. As a result, mine rescue team behavior data were separated in the analysis and are reported in this article. By considering the responses from mine rescue team members and trainers, it was possible to sort the data and identify seven key areas of importance to them. On the basis of the responses from the focus group participants with a mine rescue background, the authors concluded that accurate and complete information and a unity of purpose among all command center personnel are two of the key conditions needed for an effective mine rescue operation.

Advanced approach to assess and improve underground mine evacuation using discrete-event simulation and animation

An advanced approach is presented to use discrete-event system simulation for a better evaluation of various configurations for emergency evacuation operations in underground mines. The mine system evacuation simulation (MSES) models are introduced and demonstrated as a powerful and cost-effective tool for improving emergency response protocols/procedures and planning rescue equipment in underground mine operations. These simulation and animation models can assist mining personnel, rescue teams, and engineers in designing, training, and investigating a wide range of 'what if?' questions in both rescue and evacuation attempts in case of disasters or mine emergencies. A simulation model of an underground metal mine with an animation interface was developed using GPSS/H® and Proof Professional®, discrete-event system simulation and animation programs, to analyse the mine's emergency evacuation plans. The simulation results provided realistic estimates of mine evacuation times for different scenarios under certain circumstances.

Gas Concentration Prediction Based on the Measured Data of a Coal Mine Rescue Robot

The coal mine environment is complex and dangerous after gas accident; then a timely and effective rescue and relief work is necessary. Hence prediction of gas concentration in front of coal mine rescue robot is an important significance to ensure that the coal mine rescue robot carries out the exploration and search and rescue mission. In this paper, a gray neural network is proposed to predict the gas concentration 10 meters in front of the coal mine rescue robot based on the gas concentration, temperature, and wind speed of the current position and 1 meter in front. Subsequently the quantum genetic algorithm optimization gray neural network parameters of the gas concentration prediction method are proposed to get more accurate prediction of the gas concentration in the roadway. Experimental results show that a gray neural network optimized by the quantum genetic algorithm is more accurate for predicting the gas concentration. The overall prediction error is 9.12%, and the largest forecasting error is 11.36%; compared with gray neural network, the gas concentration prediction error increases by 55.23%. This means that the proposed method can better allow the coal mine rescue robot to accurately predict the gas concentration in the coal mine roadway.

Kinect-Based Vision System of Mine Rescue Robot for Low Illuminous Environment

This paper presents Kinect-based vision system of mine rescue robot working in illuminous underground environment. The somatosensory system of Kinect is used to realize the hand gesture recognition involving static hand gesture and action. AK-curvature based convex detection method is proposed to fit the hand contour with polygon. In addition, the hand action is completed by using the NiTE library with the framework of hand gesture recognition. In addition, the proposed method is compared with BP neural network and template matching. Furthermore, taking advantage of the information of the depth map, the interface of hand gesture recognition is established for human machine interaction of rescue robot. Experimental results verify the effectiveness of Kinect-based vision system as a feasible and alternative technology for HMI of mine rescue robot.

Application of the Motion Control System for Mine Rescue Robots

The solution of motion control system is proposed, researched and developed according to six-pedrail mine rescue robot. According to different motion types, motion analysis of main drive module and armdrive module is analyzed individually. The method of modular design is used by hardware part and soft part of motion control system of mine res- cue robot. Hardware part includes host computer module, main drive module and arm drive module. The Hall sensors are used by position control or velocity control of main drive module and arm drive module. The soft part includes host com- puter module program, main drive module program and arm drive module program.A series of experiments of motion control system of mine rescue robot is done, and data of experiments is analyzed in the end. The research shows that mo- tion control system developed meets the requirements of mine rescue robot because of good precision and real-time.

Physical Training Methods For Mine Rescuers In 2015

Abstract We have studied physical mine rescue training programs and health-related and rescue-related fitness tasks during a mine rescue competition, made in China and Australia and on these basis we have design our own pre physical training method. We have stored the heart rate measured in bites per minute (bpm) during the 2012 year periodical training for 21 mine rescuers. We have designed a physical training procedure based on six training models: Body Building, Method of isometric efforts, Method of Interval Training, Volume variation method, Structured method for basic grip and release and Specific work method. Then we measured again during the 2014 year periodical training, the heart rate for the same mine rescuer having the physical training procedure performed before. We have notice that the trained person have now lower bpm, during the tests that could represent better performances during the rescue actions. Our research were made in the Laboratory for Risk-Rescue Operations of the INCD INSEMEX Petroşani, Romania.

Health status and physical fitness of mines rescue brigadesmen.

The aim of the study was to assess health status of regular and part-time mines rescue brigadesmen. A group of 685 mines rescue brigadesmen was examined within the preventive testing - a basic internal, biochemistry and anthropometric examination, physical fitness testing. The average age of the subjects was 41.96±7.18 years, the average exposure in mining was 20±8.1 years, out of that 11.95±7.85 years as mines rescue brigadesmen. Elevated levels of total serum cholesterol (T-CH) and low-density lipoprotein cholesterol (LDL-CH) were found in over 1/2 of the subjects. Systolic hypertension (systolic blood pressure (SBP) ≥ 140 mm Hg) was confirmed in 34%, overweight (body mass index (BMI) ≥ 25) in 62.3% and obesity (BMI ≥ 30) in 20.4% of the examined mines rescue brigadesmen. The metabolic syndrome was found in 15.2% of persons. The highest physical fitness was found in mines rescue brigadesmen and the lowest in mine officers. Limit values of maximum oxygen uptake (VO2 max/kg) determined by the management of the mine rescue station were not reached by every 3rd of all mines rescue brigadesmen. Compared with the control group of the Czech and Slovak population, the rescuers are taller, have greater BMI, higher percentage of body fat in all age categories and proportionally to that they achieve a higher maximum minute oxygen uptake; however, in relative values per kg of body weight their physical fitness is practically the same as that of the controls. The prevalence of risk factors of cardiovascular diseases and VO2 max/kg in the group of the mines rescue brigadesmen is comparable with that in the general untrained Czech population.