Wireless Sensor Network based Alert System for Cold Chain Management

A cold chain is a temperature controlled supply chain. The chain that brings the temperature-sensitive products from the factory to the consumer through an uninterrupted series of steps under a controlled temperature is usually called the “cold chain.” The goods follow complex logistic paths along this chain, and the final distribution often requires the use of refrigerated vehicles. While the temperature is easily controlled and monitored in the factory plants, the refrigerated vehicles can be a crucial point in the whole chain, since the products may undergo transient conditions during the loading operations or even during the whole transport process with great risk to the integrity of the goods. The refrigerated vehicles have to satisfy some thermal requirements, which are mainly related to the insulation and refrigeration capabilities, but this does not assure product integrity because of the unpredictable condition that may occur during the transportation and that could cause a significant change in the product temperature. The only reliable way of verifying the real integrity of the cold chain consists of monitoring the temperature of the products during their distribution. Application proposed in this paper deals with a wireless sensor network that has been specifically designed to monitor temperature-sensitive products during their distribution, with the aim of conforming to the cold-chain. Here sensors are placed along the cold boxes, such as product nodes communicate through a wireless channel with a base station which collects and processes the data sent by all nodes. This will continuously monitor temperature and multiple level of alert is provided in case of any undesirable condition in the product. The alert messages are forwarded to the vehicle driver and to the producer of the product.