Informatics, TU Vienna

A High-Performance Arbitration Scheme for EtherCAT

EtherCAT is a popular Ethernet-based solution conceived for connecting devices at the shop-floor in automated factory environments. At present, it is probably the industrial Ethernet solution featuring the highest degree of communication efficiency.

The Automation Systems Group of the Institute of Computer-Aided Automation invites to the following talk:

Abstract

EtherCAT is a popular Ethernet-based solution conceived for connecting devices at the shop-floor in automated factory environments. At present, it is probably the industrial Ethernet solution featuring the highest degree of communication efficiency. Its access protocol is based on a master/slave approach, where a single master inquires and sends commands to a (potentially very large) number of slave devices. Despite permitting thousands of I/O points to be periodically exchanged between the PLC and decentralized peripherals with cycle times well below 1ms, EtherCAT is not able to cope in a proper way with event-driven systems. In these cases, in fact, a number of intelligent devices have to be interconnected that interact asynchronously by producing real-time process data on a sporadic – and mostly unpredictable – basis. Many distributed control systems are currently based on such an approach. In order to resolve possible contentions when accessing the shared communication support, the related communication solutions usually rely on suitable arbitration schemes carried out on message priorities.

Ethernet Networked Embedded Control Systems Technology (EtherNEXT) is a proposal for enhancing basic EtherCAT so as to make it suitable for this kind of systems as well. The behavior of the resulting network resembles somehow Controller Area Network (CAN), but is able to run at the Ethernet speed (i.e., 100Mb/s). As this solution has been conceived as a proper extension of EtherCAT, conventional and “enhanced” devices are enabled to coexist in the same network.

Biography

Gianluca Cena (Senior Member, IEEE) is Director of Research with the Istituto di Elettronica e di Ingegneria dell'Informazione e delle Telecomunicazioni of the Italian National Research Council (IEIIT-CNR). He received the Laurea degree in Electronic Engineering and the Ph.D. degree in Information and System Engineering from the Politecnico di Torino, Italy, in 1991 and 1996, respectively. His current research interests include industrial communication systems, wired and wireless networks and, in particular, real-time protocols. Present teaching activities include industrial and automotive networks, as well as industrial informatics and field networks. Dr. Cena is an Associate Editor of the IEEE Transactions on Industrial Informatics.