SPS IPC Drives Italia
Parma, Italy Hall 5, Booth H041
Sercos presents Industry 4.0-capable demo, Sercos over TSN, Sercos SoftMaster and further demos at SPS IPC Drives Italia
Information and communication technologies play a key role in implementing Industry 4.0 concepts. Our modern data bus systems must not only guarantee that machines and facilities can carry out production with safety and precision. They also have to enable consistent access to data relevant to production from any company departments and locations on devices at field level. An Industry 4.0 demonstrator from Sercos International highlights how process and device data are made available not just locally via the real-time bus, but also via OPC UA for a whole range of different application scenarios in a uniform and cross-manufacturer manner.
This makes data exchange between machine peripheries and superior IT systems easier and also supports the requirements of Industry 4.0 regarding semantic interoperability.
The multi-protocol capability from Sercos® makes various implementation options possible at the same time. One option is that the OPC UA server functionality can be integrated into a machine control. In this case, the control acts as a gateway in which the mapping onto Sercos services and data is implemented. With Sercos III it is also possible to integrate an OPC UA server directly into a Sercos field device (drive, I/O station or sensor). In this case, the OPC protocol is routed directly to the relevant Sercos slave device. The gateway functionality of the control is thus reduced to the function of an Ethernet switch. Due to the Sercos transmission process (no tunneling!), the ability of an OPC client and an OPC UA server to communicate with each other is preserved even without continuous Sercos communication.
If the control wants to pass on the data of the connected field devices filtered or aggregated to the superimposed OPC UA clients, an OPC client can also be integrated into the control. This makes the data collected via Sercos available to other OPC UA clients in edited form via an OPC UA server.
The user organization will also present the Sercos TSN demonstrator for the first time SPS Italia.
The demonstrator, which attracted a lot of interest at SPS IPC Drives 2016 in Germany, shows the transmission of the Sercos III real-time protocol via Ethernet standard IEEE 802.1 TSN (Time-Sensitive Networks).
The Sercos TSN Demonstrator was created by the Institute for Control Engineering of Machine Tools and Manufacturing Units (ISW, University of Stuttgart) with support of several industry partners. It shows a real-time and multiprotocol-capable network infrastructure based on TSN for automation technology.
The demonstrator involves a TSN-based Sercos III SoftMaster with a Soft CNC from Industrielle Steuerungstechnik GmbH (ISG), which communicates with Sercos III servo drives from Bosch Rexroth via Hirschmann Automation TSN switches. Through this TSN network infrastructure, video streams of a webcam are transmitted to a remote display in parallel with the servo communication, without impairing the characteristics and functionality of the Sercos real-time communication.
The demonstrator constitutes a proof of concept,with which the native real-time capability of Sercos within a TSN network is presented on an exemplary basis.
Ethernet standard IEEE 802.1 brings with it mechanisms that ensure open, real-time-capable communication and also support high, future data rates. A key aspect here is the IEEE 802.1Q standard, which specifies the division of physical networks into several logically separated, prioritized virtual networks (VLANs). In turn, the VLAN priorities enable optimized scheduling of the packages from all virtual networks, with transmission safety and a deterministic latency. To create a uniform time base in the entire network and to transfer the traffic classes within synchronous time slots, mechanisms from IEEE 802.1-AS / IEEE 1588 (distributed clock synchronization) and IEEE 802.1Qbv (time-multiplex procedure) are used.
The aim in designing the demonstrator was to expand a typical setup consisting of a numerical control and drives by adding an interposed, real-time-capable network. A key element here was the integration of the Precision Time Protocol (PTP) according to IEEE 1588 into the control, so that all network participants use a uniform time base. In the analysis of the real-time behavior, it was shown that the errors in the time synchronization were restricted to a two-digit nanosecond range. With this analysis, it could be proven that the synchronization,which is also contained in the TSN standard as IEEE 802.1-AS, achieves accuracy that is sufficient for demanding motion applications. Additional analyses on the demonstration system will establish the limits of real-time communication of Sercos via TSN by varying the cycle time and the number of participants.
Sercos International will also show the Sercos SoftMaster Demo. This demo is based on a Sercos III SoftMaster core, which was developed in cooperation with Bosch Rexroth and is being made available as open source software.
A Sercos III FPGA or ASIC master component is not required because a standard Ethernet controller is used instead, with the Sercos III hardware functions emulated in host-based driver software. With this implementation approach, adequate real-time behavior is ensured for a large number of applications. If an Ethernet controller with several queues and telegram scheduling (such as the Intel I210™) is used, even the synchronicity and the highest availabilities of a hardware-based master can be achieved.
Unlike the previous solution with a hardware-based Sercos master, with the Sercos SoftMaster machine, engineers and control manufacturers can now use an industrial PC without special fieldbus hardware and without PCI slots to control the machine. Due to the use of the Sercos SoftMaster in combination with the powerful Intel I210, the CPU load is reduced significantly, while costs and space are also saved.
The Sercos SoftMaster is available as an open source software license for general use in the software pool of Sercos International e.V.
With the provision of a Sercos III SoftMaster implementation as an open source, it becomes much easier for manufacturers to develop a Sercos III master and at the same time to participate in future improvements and expansions of the software. Control systems can be designed more affordably and will be simpler and more compact in the future.
In addition to the Sercos SoftMaster demo, additional demos as well as a large number of exhibits forming a cross section of the approximately 250 Sercos-capable products will be displayed in the Sercos stand.« Back to overview