Abstract: The current vibration detection system has the problems of large delay, poor controllability of sensor network and low detection precision. In order to solve the problems, a new vibration detection system based on Process field bus (Profibus) technology was proposed. Firstly, the complex calculations such as Kalman filtering and Fast Fourier Transform (FFT) were implemented at each node of detection device. The network load was reduced by about 95% compared with the traditional scheme of transmitting large amount of original vibration data, the network transmission time and the computing time of workstation were shortened, the real-time performance and computing power of system were improved. Secondly, the Profibus protocol was used to realize the management and data transmission of the vibration detection device network, which ensured the stability and controllability of the sensor network. In addition, the high-precision vibration sensor was used on the vibration detection node device, and the vibration data was filtered on the detection node. The detection precision was up to 0.0039 mg. What's more, the function customization and secondary development of detection device were convenient by the independent design and development of the Profibus protocol slave station. The RT-Thread embedded system kernel was used to achieve resource allocation and task scheduling on the detection node device, and the real-time performance and reliability were improved. The experimental results show that, the proposed system can process the original vibration data of the vibration field quickly, and transmit the processed data to the workstation computer with high real-time performance. Meanwhile, the Profibus network composed of vibration detection devices can display the status information of node in real-time and remind users promptly when there is a network fault. The network has good controllability.

Key words: vibration detection, Profibus, data processing, embedded system, sensor network

摘要： 针对当前振动检测系统延迟大、传感网络可控性差、检测精度低等问题，提出了一种基于过程现场总线（Profibus）技术的振动检测系统。首先，在每个检测设备节点处实现卡尔曼滤波、快速傅里叶变换（FFT）等复杂计算，使网络负载与传输大量原始振动数据的传统方案相比降低了约95%，缩短了网络传输时间和工作站的计算时间，提高了系统的实时性和计算能力。然后，采用Profibus协议实现对振动检测设备网络的管理和数据传输，保证了传感网络的稳定性和可控性；并且，在振动检测节点设备上使用高精度振动传感器，在检测节点上对振动数据进行滤波等处理，检测精度高达0.0039 mg。此外，自主设计开发了Profibus协议从站，方便检测设备的功能定制与二次开发；在检测节点设备上采用RT-Thread嵌入式系统内核实现资源分配与任务调度，提高了实时性和可靠性。实验结果表明，所提系统可以快速地对振动现场的原始振动数据进行数据处理并把处理后的数据传输到工作站电脑，实时性高。同时，振动检测设备组成的Profibus网络可以实时显示节点的状态信息，若有网络故障能够及时提醒，网络的可控性好。

关键词: 振动检测, Profibus, 数据处理, 嵌入式系统, 传感网