Transmitting measured data by wireless in real time

In manufacturing plants everywhere, sensors continuously record measurements in plant and machinery to check that everything is running according to plan and to enable any errors in the industrial production environment to be recognised at an early stage. However, as a rule, evaluation of the data is decentralised and takes place after a time lag. In contrast to this, the 5G wireless standard permits direct, wireless measurement in real time. Fraunhofer in Aachen has teamed up with Ericsson to offer a unique test environment for 5G applications in industry.

A good example to test with is the production of aircraft engine components.

The production of aircraft engines is a complex and expensive business. The whole manufacturing chain of a compressor component known as a blisk (blade-integrated disk) can cost up to €200,000. The highest levels of safety and quality must be observed and computer-controlled machine tools have to be programmed to ensure that the components are produced exactly as stipulated in the design plans. Sensors mounted on plant and machinery monitor the production process continuously.

“There is always a certain element of residual risk because the quality analysis is decentralised with a considerable time lag,” said Dr Sascha Gierlings, head of Prototype Manufacturing at the Fraunhofer-Institute for Production Technology IPT. “The natural frequencies of the thin-walled blades present a particular problem in production as any uncontrolled vibration has adverse effects on the quality, which have to be corrected via time-consuming manual operations afterwards.”

A combination of the latest sensor technology and rapid data transfer rates such as those provided by the future mobile communication standard 5G seems to be a promising solution to this problem. In the specific case of blisk production, the Fraunhofer IPT has attached a specially developed sensor directly to the component. This transfers the vibration spectrum of the blisk via 5G with submillisecond latency to software that recognises immediately whether the vibrations exceed the permitted maximum or have reached critical frequencies — and adapts the production process accordingly without delay. An additional advantage of the rapid data transfer is that it allows a digital twin, the virtual reflection of a component, to be generated. This twin helps to answer important questions relating to the production process at the computer, before the process begins.

The live transfer of component data was developed by the Research Institute in Aachen in collaboration with Ericsson, the Swedish technology provider in the High Performance Center Networked, Adaptive Production. The partners unveiled their solution to the public for the first time in a live demo at the Hanover Fair at the end of April: the researchers from the Fraunhofer Institute transferred the vibration spectrum of a milled blisk via 5G technology in real time directly from the sensor to a display unit.

“We hope that we can encourage all interested companies to visit us in Aachen so that they can profit from the unique test environment we have here for 5G applications in industry,” added Niels König, manager of the Production Metrology Department and coordinator of 5G activities at the Fraunhofer IPT. “Blisk production is only one of many conceivable fields of application. Its complexity, however, makes it particularly suitable for use as a demonstrator.”

“Examples of applications such as blisk production highlight the fact that there is no way round 5G for those striving to futureproof their production,” explained Stefan Koetz, CEO of Ericsson. “Of course, when you are creating solutions to connectivity as part of Industry 4.0 it is essential to work side by side with a solid partner with a track record of integrity as well as with unsurpassed standards in quality and reliability.”

Plans are already well underway to introduce 5G as the new mobile communication standard by 2020. In addition to low latency times, it promises high data transfer rates of up to 10,000 Mbps and allows for numerous devices to be operated simultaneously in closely linked small radio cells. For the first time ever, 5G technology will accommodate the use of wireless sensor connections for real-time data analysis and adaptive control of production processes with short reaction times. “The greatest challenge facing mobile communications providers from now until 2020 will be to continue to reduce the size of transmission units,” said König. “From laptop to smartphone or chip size, if possible.”

Image: A sensor transfers the vibration spectrum of the blisk via 5G with submillisecond latency. © Fraunhofer IPT.