Design Of Mine Safety Wireless Monitoring System Based On STM32

Coal mining belongs to underground operation,abnormal physiological state may directly affect the working state of miners,once the operation error may lead to coal mine accident.Moreover,after the accident,if the trapped personnel cannot be found in time,their life safety will be seriously threatened.In addition,during the COVID-19 pandemic,poorly ventilated mine conditions made it easier for the virus to spread quickly.Therefore,the life safety of miners needs to be paid more attention to.In view of the above problems,the traditional mine safety monitoring equipment has shortcomings of single function,big error and not enough portability.Therefore,this paper designs a wireless monitoring system for mine safety based on STM32,which integrates the monitoring of collective temperature,heart rate and position.In daily work,the system can alert people when their body temperature and heart rate are abnormal or people enter dangerous areas,and provide convenience for personnel scheduling at work.After an accident,the system can provide an effective reference for finding trapped people and selective rescue.The research content of this paper generally includes two parts: upper computer and lower computer.(1)In the lower part,with the core controller of STM32 single chip microcomputer,the system collects the information of temperature,heart rate,position and acceleration of personnel respectively through LMT70 temperature sensor,ADS1292 heart rate sensor,DW1000 radio frequency transceiver and MPU6050 motion sensor.The system uses mean filtering technology and data fitting method to calculate the body temperature of personnel,and uses FIR(Finite Impulse Response)filtering technology and FFT(Fast Fourier Transform)algorithm to calculate the heart rate of personnel.Kalman filter technology,DS-TWR(Double Side-two Way Ranging)Ranging algorithm and three-side centroid positioning technology are used to calculate the position of personnel,and auxiliary positioning is performed through the judgment of motion state.In the lower part of the system,the system display the temperature,heart rate and position of the personnel by the OLED screen,and the alarm will be issued when the data is abnormal by judging the threshold value.The system adopts ZigBee protocol-based Mesh network to build a large-range,multi-node wireless network.Through the network,the temperature,heart rate and position of each terminal node are sent remotely to the coordinator,that then sends the personnel data to the upper computer through the serial port.(2)In the upper part,the system uses Qt as a graphical interface development tool,the design of the upper computer data monitoring software,which can realize the digital display of temperature,heart rate and position as well as the graphical coordinate display of the position of the personnel,and the upper computer in the abnormal data when the alarm.In addition,the upper computer can also mark the underground dangerous area by setting up an electronic fence,and mark the personnel entering the area,so that the supervisors can timely find the personnel entering the dangerous area.After many experimental tests,the average error of body temperature is 0.1?,the average error of heart rate is 3%,and the comprehensive average error of personnel position is 9 cm.Part of the data from the lower computer can be transmitted normally to the upper computer and displayed digitally and graphically.The experimental results indicate that the system can accurately detect the human body temperature,heart rate and position,and can be monitored in real time through the upper computer,to achieve the desired effect,has a certain practical value and practical significance.