2016 has the AIM-D Association in cooperation with the OPC Foundation a new communication standard for Auto ID devices. At the last SPS IPC Drives in Nuremberg it was shown that this standard is accepted by many device manufacturers and their users across the entire Auto ID spectrum. Harting was in the boat right from the start.
Motivated by Siemens and Harting, the AIM System Integration Workgroup decided in 2014 to define a new, future-proof, technology- and manufacturer-independent communication standard for the Auto ID (Automatic Identification and Data Acquisition) industry. Until now, many devices had communicated via proprietary interfaces. In addition, different communication standards often applied to different technologies. Say, whether barcode or UHF, RFID also had an influence on the programming of the communication interface of the software to be connected. These conditions had grown historically.
Auto ID as a base technology for 4.0 industry
Containers, circuit boards, automobile bodies, hospital beds and much more are now automatically identifiable thanks to Auto ID technology - usually completely passive without any maintenance on the object. With UHF RFID (also called RAIN RFID), the object itself still has a memory. Information such as the date of manufacture and the firmware version of a printed circuit board can be stored directly on the printed circuit board, in this example, without power, wirelessly retrievable or updateable.
Today, Auto ID technology is a natural tool to deliver a total solution, such as: As an automatically operating warehouse logistics center to realize. Communication barriers are undesirable. Which Auto ID technology is used for which purpose, should also decide the use case and not the communication interface of the Auto ID device. In addition, classical communication structures such as the automation pyramid are broken up. Today, an RFID reader communicates directly with an ERP system as well as with a PLC on the production line.
Motivated by these ideas and requirements, the AIM working group decided to define a communication interface based on OPC UA. OPC UA is one of the standards for the realization of modern communication architectures and is also listed in the RAMI specifications of the Federal Government on the subject of industry 4.0. In addition, OPC UA is already supported by many PLCs and software systems. Communication to the machine and to the database system in the cloud is so easy to realize. OPC UA is the communication standard of the automation industry. There is almost no supplier for this industry and almost no machine manufacturer who does not already offer an OPC UA interface today.
Thanks to its object-oriented structure, OPC UA is very well suited to developing a common communication standard for a wide variety of Auto ID technologies. Similarities such as a scan method for the simple recognition of an ID can be defined in parent classes. Specific characteristics can be implemented in derived classes for each Auto ID technology. With this mechanism, vendor-specific extensions based on the standard can be entered without questioning the common basic functionality.
Safety instaled right away
Communication security is also an important topic. Isolated communication systems are also becoming less and less common in production or logistics. As already mentioned, the vertical and horizontal integration of Auto ID systems is crucial today to create a total solution. OPC UA already offers several integrated security mechanisms. This was also tested by the Federal Office for Information Security (BSI). The BSI has confirmed that OPC UA already integrally offers mechanisms for implementing secure data communication. The BSI says: "OPC UA was developed under security aspects and contains no systematic security gaps". For Auto ID systems this aspect is not negligible. After all, based on the data communicated by the AutoID system, complete machines and processes work largely autonomously.
The topic of security, not only from the point of view of communication to PLC or computer system, the members of the AIM Association generally considered important. AIM Germany has therefore founded its own working group "Auto ID + Security" in the year 2018. This working group develops recommendations for action on how to safely use the Auto ID technology.
OPC UA has gained even more importance since 2016. The entry of the Volkswagen Group into the OPC Foundation in the year 2018 shows that one of the key sectors of Germany and Europe, the automotive industry, also considers OPC UA important. On the 21. May 2019, the German Automobile Manufacturers Automation Initiative (AIDA) in cooperation with the German Engineering Federation (VDMA) in cooperation with the OPC Foundation is organizing an OPC UA Information Day for automotive suppliers at Volkswagen in Wolfsburg. This also shows that users of Auto ID technology demand OPC UA.
Auto ID devices with OPC UA interface
The OPC Unified Architecture for Auto ID Companion Specification released in 2016 has now been integrated into the devices by many Auto ID manufacturers. As can be seen at the OPC Foundation booth at the SPS IPC Drives in November 2018, barcode, HF and UHF devices with OPC UA interface are now available. Currently we have different Auto ID technologies, but a common communication standard. Uniform, secure data communication with a wide variety of devices from different manufacturers is thus a reality based on OPC UA, the future-proof communication standard in the automation industry.
Of course, the Auto ID devices of each manufacturer continue to differ. Differentiation options have the devices on enough. Only the data exchange is standardized. This simplifies the integration of Auto ID technology. Thanks to "inbuild security" the security of the communication increases with correct application. This accelerates the expansion of automation towards Industrie 4.0.
Future work of the working group
But the workgroup system integration did not finish its work in the year 2016. The participants are constantly working to expand and improve the interface specification. The tasks are manifold. A key issue is the simplification of the interface for - from Auto ID view - simpler application scenarios. This should speed up implementation and interface integration and eliminate unnecessary hurdles. So in the future a simple scanning of a single object can be achieved purely by variables. Function calls are no longer required. The implementation effort is reduced to the minimum.
Another important topic is the integration of sensor data. In particular, the RAIN RFID technology is increasingly used for the transmission of sensor values. In this way, objects can be clearly identified, additional data read and the current object states queried. Information on whether the gearbox is too hot, the body moist or the container is securely locked can be queried directly. Often even batteryless - passive and without additional maintenance.
The individual technologies merge more and more. Classic sensors and Auto ID grow together.
AIM Germany also took up this aspect in an additional working group "RFID + Sensor Technology" in the year 2018. Of course, the results and recommendations of this working group will also be taken into account when expanding the OPC UA based interface. There is also an international exchange about the RAIN or AIM North America Association.
The latest release of the OPC Unified Architecture for Auto ID Companion Specification by AIM Germany in cooperation with the OPC Foundation has been presented at the Hannover Messe 2019. First results of the above-mentioned work packages are already included here.
The author (picture) is Olaf Wilmsmeier, RFID Business Development Manager, Harting IT Software Development and Board Member of AIM-D.
Picture above: from left: Stefan Hoppe, President and Executive Director OPC Foundation; Bernd Wieseler, Chairman of the AIM-D System Integration Working Group, Hans Turck GmbH & Co. KG; Olaf Wilmsmeier, Board Member of AIM-D, Harting IT Software Development GmbH + Co. KG; Matthias Damm, Member of OPC Foundation technical advisory council, ascolab GmbH