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Nowadays, the using of real-time Ethernet (RTE) in CNC system becomes a main trend because of its low cost and high performance. In order to guarantee the performance of CNC systems which use RTE, the characteristics of RTEs must be tested according to the description in IEC61784-2 standard. In this paper, the performance indicators (PIs) described in IEC61784-2 are analyzed and the testing approaches for some selected PIs which are closely related to CNC system performance are researched. According to these PIs, the hardware and software of RTE performance testing system are implemented. With this system, the evaluation of RTEs which are going to be used in CNC system can be more general purpose to fit to different RTE communication profiles (CPs) and the accuracy of sampling can be less than 10 ns. Also, with the designed flexible software structure, analysis software can adapt to different kinds of RTE CP testing. Testing scenario and a case study for the test of EtherCAT are also given to show the feasibility of the designed testing system. With the testing system designed in this paper, the evaluation for RTEs which will be used in CNC system can be done in a simple way to guarantee the CNC system performance. [ABSTRACT FROM AUTHOR]

Nowadays, Ethernet networks have been extended down into the field of automation control from the upper planning and scheduling level, which caused the generation of a new form of communication using real-time industrial Ethernet fieldbus. This paper presents a feasible Ethernet-based real-time feildbus scenario for industrial automation control systems. It endeavours to gain high performance in general synchronisation real-time control systems with common hardware and software resources. For this purpose, a master-slave pattern is adopted in constructing the communication protocol. The slave nodes are developed based on universal FPGA and ARM chips, and the first slave node is in charge of precise cyclic timing and synchronisation among all slave nodes with time resolution of 20 nanoseconds. The master protocol stack is developed under Linux using Real Time Application Interface (RTAI), which not only provides application interface for user programs but also is responsible for exchanging process data with slave nodes in real time. A case study of merging this fieldbus into EMC2 to control a three-axis milling machine is also discussed and implemented. The experiment results show that this industrial Ethernet fieldbus platform completely meets the demand of open industrial automation control application. [ABSTRACT FROM AUTHOR]