Automated Railway Crossing System Using ZigBee/IEEE 802.15.4 Standard
This paper presents a development of an automatic railway crossing system using a wireless sensor network based on ZigBee/IEEE802.15.4 standard. The existing works on automatic railway crossing system apply some technologies such as Fiber Optic, Coaxial Cable, and General Packet Radio Services (GPRS). However, they require high cost in their operation and complex installation. ZigBee allows us to develop a system with low power, low price that is suitable for automatic railway crossing system. We develop a new system that consists of four main parts, i.e. railway detector, ZigBee Wireless Communication Device, railway crossing gate, and monitor system. We propose an optimal recovery path routing algorithm based on ZigBee protocol in API (Application Programming Interface) mode to ensure the reliable data transmission from the source node to the destination node. Each node has two paths connecting to the neighboring nodes, where the transmission probability to the closer neighboring nodes is higher than that to farther nodes. The data are sent by the sensor node to monitor system and are displayed as the status of network link, status of the train detection, status of the railway crossing gate, and status of the sensors node in real time. From the data displayed in the monitor, we can also detect if there are any malfunctions on the sensor nodes. So we can fix the problem immediately. Moreover, the hardware system consists of solar cell panel, charger control unit, and battery storage designed for self- energy management and low power consumption. These features are suitable for installation in real environment. As a prototype of an automatic railway crossing system, the developed system in this project is very useful for further development and application in railway crossing system management in Thailand.