The emergence of industrial control networks for manufacturing control, diagnostics, and safety data : There is wide use of ethernet for system diagnostics and control, and inclusion of safety features on the same network is being debated; the trend is towards wireless communications
James R. Moyne, Dawn M. Tilbury · Proceedings of the IEEE · 2007
The most notable trend in manufacturing over the past five years is probably the move towards networks at all levels. At lower levels in the factory infrastructure, networks provide higher reliability, visibility, and diagnosability, and enable capabilities such as distributed control, diagnostics, safety, and device interoperability. At higher levels, networks can leverage internet services to enable factory-wide automat- ed scheduling, control, and diagnostics; improve data storage and visibility; and open the door to e-manufacturing. This paper explores current trends in the use of networks for distributed, multilevel control, diagnostics, and safety. Network performance characteristics such as delay, delay variability, and determinism are evaluated in the context of networked control applications. This paper also discusses future network- ing trends in each of these categories and describes the actual application of all three categories of networks on a reconfigur- able factory testbed (RFT) at the University of Michigan. Control, diagnostics, and safety systems are all enabled in the RFT utilizing multitier networked technology including Device- Net, PROFIBUS, OPC, wired and wireless Ethernet, and Safe- tyBUS p. This paper concludes with a discussion of trends in industrial networking, including the move to wireless for all categories, and the issues that must be addressed to realize these trends.