While rail freight transportation is gradually becoming a crucial asset in the context of decarbonization of the transport sector, new standards and requirements in this field aim at improving the safety and reliability of freight vehicles and the infrastructure. From this perspective, Condition Monitoring and Condition Based Maintenance are becoming essential tools to improve systems reliability through the use of in-service instrumented vehicles. On the contrary of high-speed applications, freight trains are actually not provided with any monitoring systems able to carry out this kind of analyses. In this context, an innovative hybrid monitoring system composed by wireless sensor nodes and a gateway was developed to be suitably mounted on a freight wagon. Sensor nodes, power supplied by solar energy, are able to carry out synthetic indices from vibration measurements, while the gateway acquires correlated GPS and odometry information. In order to take advantage of the acquired data, a software based on a geo-localization algorithm created for high-speed applications was developed in order to correlate vibration data to the railway line mileage. A field campaign allowed to test the system on a real freight wagon and to acquire many experimental data. Using the collected experimental data, in the paper is shown how the developed software can be used to perform diagnostic activities of the infrastructure. Moreover, it is demonstrated that relying on the only GPS information is sufficient to get enough accurate georeferenced data for freight trains applications. This paves the way to the future development of a completely wireless system able to perform condition monitoring of both the vehicle and the infrastructure minimizing the impact on the vehicle.

中文翻译：

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基于地理定位振动测量的货运列车状态监测无线传感器节点

虽然铁路货运逐渐成为运输部门脱碳背景下的重要资产，但该领域的新标准和要求旨在提高货运车辆和基础设施的安全性和可靠性。从这个角度来看，状态监测和基于状态的维护正在成为通过使用在役仪表车辆来提高系统可靠性的重要工具。与高速应用相反，货运列车实际上没有配备任何能够进行此类分析的监控系统。在此背景下，开发了一种由无线传感器节点和网关组成的创新混合监控系统，以适合安装在货车上。传感器节点，太阳能供电，能够从振动测量中执行​​综合指数，而网关获取相关的 GPS 和里程计信息。为了利用获取的数据，开发了一种基于地理定位算法的软件，用于高速应用，以便将振动数据与铁路线里程相关联。实地活动允许在真正的货车上测试系统并获得许多实验数据。使用收集的实验数据，本文展示了如何使用开发的软件来执行基础设施的诊断活动。此外，证明依靠唯一的 GPS 信息足以为货运列车应用获得足够准确的地理参考数据。