In 2014, the AIM System Integration Working Group decided to define a new, future-oriented, technology- and manufacturer-independent communication standard for the AutoID industry. Until now, many devices communicated via proprietary interfaces. In addition, different communication standards often applied to different technologies. Whether barcode or UHF RFID also had an influence on the programming of the communication interface of the software to be connected. These circumstances had grown historically.

Basic technology for 4.0
Containers, circuit boards, car bodies, hospital beds and much more can now be identified automatically using AutoID technology. With UHF RFID (also known as RAIN RFID), the object itself is given a memory. Information such as the production date and the firmware version of a circuit board can be stored directly on the circuit board in this example. Without power supply, wirelessly retrievable or updatable.

Today, AutoID technology is the tool for implementing a complete solution, such as an automatically operating logistics center. Communication barriers are undesirable. Which AutoID technology is used for which purpose should also be decided by the application and not by the communication interface of the AutoID device. In addition, classic communication structures - keyword automation pyramid - are being broken up. Today, an RFID reader communicates directly with an ERP system as well as with a PLC on the production line.

Various manufacturers offer OPC UA for different Auto-ID technologies. © Harting

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 German government on the topic of Industry 4.0. In addition, OPC UA is already supported by many PLCs and software systems. Communication with the machine, as well as with the database system in the cloud, is therefore easy to implement. OPC UA is the communication standard of the automation industry. Almost every provider for this industry and almost no machine manufacturer does not already offer an OPC UA interface.

Thanks to its object-oriented structure, OPC UA is very well suited to developing a common communication standard for the various AutoID technologies. Common features, such as a scan method for the simple recognition of an ID, can thus be defined in higher-level classes. Specific characteristics can be implemented in classes derived from this for the individual AutoID technologies. Using this mechanism, manufacturer-specific extensions can also be incorporated based on the standard without jeopardizing the common basic functionality.

Security built right in
Communication security is also an important issue. Isolated communication systems are also becoming increasingly rare in manufacturing and logistics. As already mentioned, the vertical and horizontal integration of AutoID systems is also crucial today in order to create a complete solution. OPC UA already offers various integrated security mechanisms. This has also been tested by the German Federal Office for Information Security (BSI). The BSI has confirmed that OPC UA already offers integral mechanisms for implementing secure data communication. This aspect should not be neglected for AutoID systems. After all, entire machines and processes work largely autonomously on the basis of the data communicated by the AutoID system.

In 2018, AIM Germany founded its own "AutoID & Security" working group on the topic of security. This working group develops recommendations on how to use AutoID technology securely. In 2016, AIM Germany presented the new OPC Unified Architecture for AutoID Companion Specification at the Hannover Messe trade fair. The first RAIN RFID devices from Siemens and Harting available on the market were presented in a demo application at the OPC Foundation's trade fair stand. OPC UA has become even more important since 2016. The Volkswagen Group joining the OPC Foundation in 2018 shows that one of the key industries in Germany and Europe, the automotive industry, also considers OPC UA to be important.

One for all
The OPC Unified Architecture for AutoID Companion Specification has now been integrated into the devices by many AutoID manufacturers. Barcode, HF and UHF devices with an OPC UA interface are now available. Different AutoID technologies but a common communication standard. Of course, the AutoID devices from the individual manufacturers continue to differ. The devices offer sufficient differentiation options. Only the data exchange is standardized. This simplifies the integration of AutoID technology. Thanks to "inbuild security", the security of communication is increased. This accelerates the expansion of automation towards Industry 4.0.

However, the system integration working group is continuing to work on expanding and improving the interface specification. One core topic is the simplification of the interface for - from an AutoID perspective - simpler application scenarios in order to speed up implementation and interface integration and remove unnecessary hurdles. Another important topic is the integration of sensor data. RAIN RFID technology in particular is used to transmit sensor values. This allows an object to be uniquely identified, additional data to be read and written and the current status of the object to be queried. Information on whether the gearbox is too hot, the body is damp or the container is securely locked can be queried directly. as