Real and virtual worlds in harmony? Production processes are coming up against their virtual limits

The vision of Industry 4.0 is taking on ever-more-tangible shape. But before it becomes reality, the task is to bring the real world of production equipment into harmony with its virtual representatives. For this purpose, virtual control of the machine tools and process simulation have to reflect everyday shopfloor reality. The obstacles still to be overcome are analysed by Dr.-Ing. Werner Herfs MBA from the Machine Tool Laboratory at RWTH University in Aachen.

Dr. Herfs, as an electrical engineer, what’s your assessment of the virtual situation?

Herfs: We are very far from utilising to the full the potentials involved. There are still a lot of questions remaining to be answered: how can cross-disciplinary information from the development process be utilised? How can we succeed in automating the formation of keywords in the CAM systems (Computer Aided Manufacturing) from real control data? How can machine variants be started up in virtual mode? What’s more, machinery manufacturers lack the tools to support them in securing the logic of their control systems (PLCs).

Where are we heading when it comes to virtual simulation of the subsequent process?

Herfs: More and more, metal-cutting production processes are coming up against their limitations, because metal-cutting tools are becoming more and more performatively capable, and the stability of the machines is no longer a given – keyword: “rattling”. The planning and simulation tools used, however, assume largely idealised physical conditions: they ignore the actual interrelationships between the process and the machine. This can be remedied by expanded models that predict non-stable machining areas during virtual running-in of NC programs between process and machine.

But won’t expanded computational models be too slow?

Herfs: In the BMBF’s (German Federal Ministry for Education and Research) project, we are researching new approaches designed to reduce the simulation times involved while retaining sufficient accuracy in the results.

How is Industry 4.0 affecting the virtual machine tool?

Herfs: More indirectly at present. The discussions themed around Industry 4.0 help everyone involved to think about new utilisation scenarios. In terms of simulation, the prudent course is not to network the behavioural or process models concerned before they have been systematically examined and comprehended – and not only so that they can be networked in the context of Industry 4.0. (Nikolaus Fecht for VDMA)