An Internet of Things Approach for Intelligent Monitoring of Conveyor Belt Rollers

This article presents an Internet of Things (IoT) architecture suitable for large scale sensor networks for condition monitoring. The developed technology has been applied and demonstrated for rotating conveyor belt rolls. Wireless sensor networks is a relatively new and emerging technology, not only capable of addressing a large number of applications in industry but is also applicable for home automation, medical monitoring, sports monitoring, etc. The presented architecture consists of a sensor platform running the Contiki operating system capable of simultaneous monitoring of several important parameters such as RPM, ball bearing temperatures, total operating hours, total laps, vibrations, and others. Electric energy is continuously scavenged from the roller’s rotation and the platform is hence operating perpetually without the need of any additional power source. All necessary components are embedded in the roller making its appearance and functionality no different from traditional rollers. This approach enables simple, automatic, and straightforward condition monitoring of conveyor belt rollers throughout their entire operating life span without any major investments in monitoring equipment and maintenance systems. The contribution of the paper is twofold: Firstly, the advantages and possibilities of using a low-power Internet-enabled sensor network for condition monitoring, with seamless integration with upper layers such as SCADA, MES and ERP are presented. Second, the use of highly-efficient EXI for CoAP is presented together with a comparison with traditional text-based XML. Comparatively, EXI show several advantages for large-scale operation of wireless sensor networks with potentially hundreds or thousands of nodes due to its bandwidth efficiency.