Study on real-time industrial control networks

• Main Author: Wu, Xuepei
• Other Authors: Xie Lihua
• Format: Theses and Dissertations
• Language: English
• Published: 2019
• Subjects: DRNTU::Engineering::Electrical and electronic engineering::Computer hardware, software and systems; DRNTU::Engineering::Electrical and electronic engineering::Industrial electronics
• Online Access: https://hdl.handle.net/10356/90139; http://hdl.handle.net/10220/48429
• Institution: Nanyang Technological University

Boosted by business trends such as Industry 4.0, Industrial Internet of Things (IIoT) solutions such as real-time Ethernet and wireless technologies have been increasingly deployed in the industrial automation sector. Higher fluctuation and less predictability in terms of customer demand promoted by Industry 4.0 can be overcome by improving the flexibility of the system via network-based control. However, closing control loops over a shared communication network means that the system performance can be highly dependent on the quality of the communication services which transfer control variables (e.g., set-point and measurement) between controllers, sensors and actuators. It is of great importance to design a common networking solution to meet real-time (and wireless) requirements in networked control systems, and maintain the backward compatibility to distributed control systems where soft real-time communication is sufficient. This thesis firstly reviews existing Ethernet-like IIoT technologies and suggests a generic communication model with multiple data channels. The scheduling of data transmissions in different channels is presented, and wireless extension scheme is suggested to integrate wireless segments into the network. The communication model is defined so that a communication backbone can be established for all types of network-based control applications, such as motion control and path tracking of automated guided vehicles (AGVs). Next, the quality of service (QoS) of the hybrid network, including cycle time, end-to-end delay and communication reliability is analyzed. Finally, a typical industrial automation system with motion control and remote AGV tracking applications is presented and discussed to demonstrate the performance of the networking scheme proposed in the thesis where a hybrid network possessing various real-time characteristics is able to satisfy multiple types of control applications described in the case study. The benefits of the solution, i.e., flexibility and scalability, can be significant to fulfil dynamic market demands in the next generation automation systems powered by Industry 4.0.