Analysis of signals generated by a magnetic sensor for detecting an approaching train in a warning system operating on railway tracks

The article discusses the issues of improving safety when performing production work near railway tracks, which are associated with a high level of risk for personnel. The purpose of this work is to develop and substantiate a promising system for notifying work crews about the approach of rolling stock, which can increase the effectiveness of safety measures at railway infrastructure facilities. The methodological basis of the study was the analysis of the causes of accidents related to the shortcomings of existing warning systems, as well as modeling the signal generated by an electromagnetic sensor when the wheel crest passes over it. To implement the system, it is proposed to use the LoRaWAN network and LoRa radio modules combined with Arduino microcontrollers. As part of the research, a structural diagram of the system and a working layout have been developed, including transmitting devices with a composition detection sensor and receiving devices integrated into workers' signal vests. As a result, a mathematical model of the signal generated by a change in the magnetic flux caused by the wheel approaching the sensor has been obtained. The dependence of the magnitude of the electromotive force on the position of the wheel relative to the coil is proved. Graphs of the dependence of the magnetic flux and the induced signal on the transit coordinate are constructed. The proposed system can be used as the main or auxiliary means of notification during repair and other work near the tracks. The conclusion is made about the prospects of the development for implementation in the industrial safety system of Russian Railways. The proposed system has high potential efficiency, can function independently and independently of weather conditions, and also serve as a reliable complement to the work of alarm systems. The introduction of this technology can significantly reduce occupational injuries at railway infrastructure facilities.