Research On Wireless Sensor Networks Node For Mechanical Vibration Monitoring

For the mechanical equipments, especially the critical and large ones, thereliability, availability, safety and maintainability relate to the productivity ofenterprises and the safety of workers’ lives. To construct the mechanical vibrationmonitoring system with the Wireless Sensor Networks (WSN) could overcome the lackof the traditional wired monitoring systems. To apply the WSN technology inmechanical vibration monitoring systems, many problems, such as high frequencyvibration signal effectively picking up, high-speed synchronous data acquisition,real-time data storage, reliable data transmission, etc, need to be resolved. Thehardware performance and computing or processing ability of most existing genericWSN node is poor, these nodes are difficult to meet the needs for mechanical vibrationmonitoring. In this paper, a mechanical vibration monitoring WSN node have beenresearched and developed, the main work are as follows.Low power consumption and high-performance synergistic dual-processorhardware architecture have been adopted. This architecture not only enhanced theoverall performance of the node, but also reduced the coupling between hardware andsoftware modules, but also facilitated the exchange and upgrade of hardware modules;High-speed SDIO interface has been used to extend high-capacity SD memory card forthe node, therefore, a high-speed large-capacity data storage system was available.Consequently, the node has obtained the ability of continuous high-speed dataacquisition and real-time storage. Instead of the traditional piezoelectric accelerationsensor and the corresponding amplifier, a high-performance high-bandwidth MEMSacceleration sensor and low power consumption programmable amplifier were adopted,which avoided the disadvantage of large power consumption and circuit complexitycaused by the traditional method of signal picking up. An independent analog to digitalconverter (ADC) have been adopted, so the node has gained a higher accuracy of dataacquisition.The software development based on embedded real-time operating systems and alayered software design style has been adopted, which reduced the coupling betweendifferent software modules and improved the transferability and readability of theprogram. In order to manage the large-capacity storage space, file system has beenintroduced into the node, which greatly facilitated the management, sharing and further processing of the acquired data.In this paper, the high frequency vibration signal picking up, continuoushigh-speed high-precision data acquisition, real-time data storage were studied.Combined with the research achievements on special wireless communication protocoland high-precision synchronous acquisition method from other members of our group,a mechanical vibration monitoring WSN node has been designed. Based on this nodeplatform, related software development and system testing has been performed.At the end of this paper, the summary and outlook of the research has been given.Further studies are expected to achieve mature industrial applications.