Wireless technology in industry has been around for a long time, WLAN and Bluetooth are used as standard for applications such as handheld scanners or automated guided vehicles (AGVs). Radio is also occasionally used for real-time-critical applications for transmitting fieldbuses and control data via wireless connections. The goals that users want to achieve by using wireless systems are diverse: for example, in moving applications within machines, where cables wear out due to constant movement, wear can be reduced by means of wireless data transmission. Wireless technology is also a problem solver in mobile applications where cables restrict mobility.

In other applications in the production environment, however, wireless systems have so far only been able to establish themselves to a limited extent. Industrial production processes require control data in real time. With existing wireless technologies, however, the transmission of real-time data for PLC control signals was only reliably feasible for relatively slow-running processes.
5G now comes with mechanisms that are designed to increase connection reliability, raising hopes that 5G can penetrate further industrial applications as a wireless technology. The 5G function MMIMO (Massive Multiple In Multiple Out), for example, promises this. MMIMO means that significantly more antennas are used than before (UMTS/LTE). This technology also enables beamforming, which allows subscribers to select the strongest of several signals. This enables better coverage and therefore greater connection stability. At the same time, more subscribers are possible with less energy consumption and - if necessary - higher bandwidth. With 5G, TSN (Time Sensitive Network) is being introduced as a real-time protocol. TSN, which has been under discussion for some time for industrial networks, is also intended to make 5G real-time capable. This means that communication cycles of <1 ms will be possible in the final expansion of 5G. Compared to today's wireless technologies, much more dynamic processes could therefore be controlled wirelessly.

Other important arguments for the use of 5G in production are simplicity and ease of maintenance. Most automation engineers are not IT specialists, and the secure operation of a WLAN network already poses enormous challenges for many today. As a general rule, machine communication errors should be able to be rectified by maintenance staff without in-depth IT knowledge and without long production downtimes, for example during the night shift. Here, wireless technology must be able to compete with the simplicity of cable networks: After all, a defective cable or switch can be replaced quickly and easily with standard electrician knowledge.

The VDMA's 5G guidelines

The VDMA's latest 5G guide aims to provide machine and plant manufacturers with a practical overview of possible applications and challenges when introducing 5G in production. One of the contributors was connection technology provider Lapp.

© Lapp

Lapp, a provider of integrated solutions in the field of cable and connection technology, has been working intensively on the topic of 5G for some time and is convinced: no wireless without cables. The company sees 5G as a supplement to its solutions and not as a threat and has therefore gladly supported the VDMA in the creation of a practical guide.

In the current publication of the guide '5G in mechanical and plant engineering - Guidelines for the integration of 5G in products and production'(download guide), the effective benefits of wireless technology were assessed with the eyes of mechanical and plant engineers using various use cases. Lapp sat at the table together with users and manufacturers. The partners were supported by Fraunhofer IIS, which provided neutral technology knowledge and methodology, collected use cases in plenary sessions and used them to reflect the capabilities of 5G. Lapp helped design two use cases and sat down with market players to openly discuss the opportunities of 5G. The result: many applications can be realized with 5G, but do not have to be, as shown by existing solutions from Lapp and other manufacturers for predictive maintenance, for example. For other possible applications, the upcoming 5G releases 16 and 17 must first show whether the real-time capability of 5G is really sufficient.

Driverless transport systems use case

A total of ten different use cases from the industrial environment are described in the VDMA's 5G guidelines. The 'automated guided vehicle systems' (AGVs) use case is of particular interest for the use of 5G:
AGVs are one of the applications well suited to 5G, the guide concludes. On the one hand, the latency times required for AGVs are within the range possible with 5G. Secondly, 5G will probably allow a shorter roaming duration than today's WLAN. The roaming duration is the time it takes to transfer a subscriber from one access point to the next. If it is too long, the AGV stops. With WLAN routes, this handover can take 30 to 50 ms. With 5G, these times are reduced as there is no need to log on and off. In addition, 5G enables significantly lower latency times - i.e. the delay time when transporting a data packet - than with WLAN. This also ensures the trouble-free operation of an AGV.

Another interesting feature of 5G is the localization function, which still has a range of 20 m with Release 15 and 3 m with Release 16. The subsequent releases are expected to further improve accuracy, which will make its use for AGVs increasingly interesting.
Another possible 5G use case is the transmission of an Ethernet-based fieldbus such as Profinet via 5G. In such a scenario, the radio technology could be integrated directly into a decentralized I/O system (remote IO). This in turn would allow the connection and transmission of multiple sensors or actuators. In moving applications, where fieldbus cables wear out in drag chains or on robots, the signals could be transmitted wirelessly without wear. The possible latency time of 5 ms would already be sufficient for this with Release 15, but not for the fast control of servo drives.

The infrastructure needs cables

The 'IoTKey' system from Lapp can transmit sensor data wirelessly to the cloud and make it available over long distances through the use of LoRa.

© Lapp

The next few decades will show whether the wireless factory is a utopia or not. Lapp is aware of the impact of 5G on the networking and data communication of the future and is preparing for it. What is exciting for the company is not only the change in data communication in the automation environment, i.e. directly in the machine and system, but also the necessary expansion of the infrastructure in the individual countries and in the factories, the so-called backbones. Specifically, this means more fiber optics, more copper cables and new antenna masts and access points. This is because the infrastructure for 5G in cities and municipalities must also be wired in the future. Only cables will enable the desired freedom of movement in factories through wireless solutions, as the access points in the halls will continue to be attached to cables. Lapp is therefore convinced that 5G and all other existing wireless technologies are an ideal complement to wired communication solutions, each with their own specific advantages and disadvantages. 5G will change many things, but not everything. However, the mobility of communication participants in industrial applications will definitely be driven forward.