Design and Implementation of IoT Platform for Electrical Resistance Tomography System

Electrical resistance tomography (ERT) is an efficient tomographic technique for the online imaging of industrial processes, primarily due to its advantages of non-radiation, realtime visualization and specific capability in performing measurements on opaque fluids. In the case of industrial applications, it requires that both the ERT hardware and software should be as reliable and flexible as possible. However, most ERT systems still employ the integrated platform, i.e., the measurement system and image reconstruction computer being placed in a short-distance, usually via a serial communication. It is usually not a good choice to employ the integrated platform, wherever the intrinsic safety is required. Therefore, an ERT platform that can realize remote data perception, dynamic data transmission and real-time data analysis is presented, which features Internet of Things (IoT) capability. The combination of the ERT system and the IoT provides a convenient and standardized interface between the on-site ERT hardware and remote monitoring devices. The measurements are made by the dedicated ERT hardware, which can be sent via Ethernet to and further processed by a highperformance workstation/server. The server performs the image reconstruction algorithms and data post-processing tasks. The HTTP protocol is also deployed in the server, from which the tomographic images and numerical data can be synchronously queried and displayed on the remote clients. Experimental results showed that the average signal-to-noise ratio of the system can achieve 66.9 dB at the applied frequency of 128 kHz, and the acquisition rate can reach 60 frames per second. The Web can be updated in every 0.1 second from a smart device. In the long term test, the proposed platform has also demonstrated high reliability and performance.