RECOVERING DATA TRANSFER CONSISTENCY OF ETHERNET-BASED COMMUNICATION IN AN INDUSTRIAL ROBOTIC APPLICATION
Abstract
The actual trend in automation control systems is to distribute control logic to modular and easy to connect production cells. As part of this trend is the increase of Ethernet technology for machine-machine data communication inside this modular based architecture. The paper presents a robotic handling application of moving parts located on a transport conveyor. Data representing a set of parameters of the parts to be handle form the conveyor is provided by a Routing Control System (RCS). The Control Management System (CMS), which controls a number of robotic cells is receiving this data from RCS and merge it with the information provided by an Artificial Vision System. The communication between these two Control Systems (RCS and CMS) is Ethernet-based. Ethernet technology is good, reliable and fast for large amount of data, but because of its non-deterministic character, it has a lack of tools for data synchronization. The paper includes an analysis of the experimental results of the measurements of the non-deterministic factor of the existing network. The "worst case scenario" of the maximum communication delay caused by Ethernet traffic and the minimum time between two consecutive data commands, shows that without recovering data transfer time-consistency, the application requirements can not be achieved. The paper is presenting a mechanism developed at protocol level, in order to guarantee the consistency in time, at CMS level, of the data provided from RCS with the data provided by Vision System.
Origin : Files produced by the author(s)
Loading...