A Remote Monitoring System For Industrial Gas Concentration Based On Android And LoRa

With the rapid development of network communication technology and intelligent mobile terminal technology,the real-time and convenience of remote monitoring system has been greatly improved.At present,the scale of industrial production is expanding,and the flammable and harmful gas is constantly derived,so it is more and more important to build a remote monitoring system for monitoring the concentration of industrial gas.The design of remote monitoring system for industrial gas concentration includes two aspects:gas detection terminal and remote monitoring technology.At present,the gas detection terminal on the market has many problems,such as single gas detection,poor stability and low accuracy,and most of them are portable,which need to be collected in the field,so the efficiency is not high and the real-time monitoring is not enough.In the application of wireless communication monitoring system,ZigBee,WIFI,3G/4G and other technologies are mostly used to communicate,and these technologies are not suitable for long distance communication,weak anti-interference ability,high cost and other shortcomings,and are not suitable for monitoring industrial site.Therefore,how to expand the communication distance,enhance the ability to resist interference,make the networking more convenient,improve the stability and real-time performance of the terminal detection instrument,has become an urgent problem to be studied in the industrial remote monitoring system.In this paper,the Long Range(LoRa)wireless transmission technology based on spread spectrum is applied to the industrial remote monitoring system.In the practical application,the diversity of industrial flammable and harmful gases and the particularity of the environment will cause certain interference to the acquisition signal.A remote monitoring system for industrial gas concentration based on Android and LoRa is designed.The whole structure of the system is divided into four parts:monitoring terminal,sink node,acquisition node and terminal multi gas detector.Among them,the monitoring terminal is divided into PC terminal monitoring and mobile phone terminal monitoring.The PC terminal is set up in the supervision control center,which is convenient for supervisors to take turns on duty monitoring.The mobile phone terminal is more convenient for users to monitor the concentration of industrial gas anytime and anywhere.The sink node not only receives the uploading data of the acquisition node through the LoRa wireless,it also uploads data to the monitoring terminal through GPRS public network or serial port,the monitoring side can also send commands through the aggregation node.The acquisition node is connected to the terminal multi gas detector through the RS484 bus and communicates with the sink node by LoRa's ultra long distance communication power.For the terminal equipment of this system,a multi gas detector based on STM32 is designed in this paper,in which the main control chip is STM32F103C8T6 microprocessor,and the temperature and humidity value and the concentration of flammable harmful gas can be detected in the industrial workshop with the corresponding sensor.In order to further improve the reliability of the system,In this paper,a suitable digital filtering algorithm is designed to reduce the interference signals in the industrial environment,thus making the data more accurate.The system has been completed and has achieved the expected requirements.The real-time detection and monitoring of combustible harmful gas can be realized well.