Cyber-physical equivalence

Smart Production Control opens the way for flexible manufacturing processes capable of producing one-off products and limited series on an industrial scale.

Smart Production Control

In the vision of industry 4.0, tomorrow’s factories will operate on the basis of digital production processes. The ability to produce more diversified and personalized products cost-effectively is no longer an unreachable dream. Manufacturers need a means of responding rapidly to customer demands in order to outpace their international competitors. Fraunhofer IGD's new technology known as “cyber-physical equivalence” could play a key role in making this possible. In the first instance, it creates a digital model of each stage in the production process, and transfers this model to the real production environment. At the same time, everything that happens in the factory is recorded as digital data and fed back into the virtual world. This opens the way for flexible manufacturing processes capable of producing one-off products and limited series on an industrial scale.

Smart production – paving the way to industry 4.0

In the past, designers had to painstakingly model new products by hand, one part at a time, whereas nowadays they usually create a digital model before making the real one. Visualization technologies connect the real world with the digital world and provide support for smart production control. The data can be accessed from anywhere using mobile devices such as tablet PCs or smartphones and visualized in an easy-to-understand form, adapted to the needs of each company and its employees. In this way, people and machines become interconnected. The term “cyber-physical equivalence” was coined to express the interaction between the real and the virtual worlds in a production process. Visual computing makes it possible to plan complex work environments and processes before they are implemented. Any discrepancies observed in the real-world process are recreated in real time in the digital planning model, where they are analyzed and solved by means of suitable adjustments.

Visual computing technologies play a key role here. “We want to provide effective support to people who work in complex production environments,” says Professor Uwe Freiherr von Lukas of the Fraunhofer Institute for Computer Graphics Research IGD (Rostock branch). “To do so, we have to gather reliable workflow data, visualize this information, and make it accessible wherever needed – be it next to the milling machine or in a shipyard’s dry dock.”

Video: Miniature production line

The benefits of cyber-physical equivalence are illustrated using a miniature production line, in which a sorting robot moves containers from one place to another. Its work sequences are recorded by a special camera that shoots ten images per second. These images are transmitted in real time to the virtual model. In the real-world scenario, a forklift will work together with the robot. But before the vehicle is introduced onto the production line, an optimum route is worked out to avoid the risk of collision with the robot. This is done with the help of a simulation in which a virtual forklift is driven around the digital model of the factory. In a cyber-physical equivalence system, data are constantly exchanged between the real and digital environments. The virtual system detects the presence of a new obstacle in real time, and modifies the truck’s route accordingly.

 

Until now, production control was a one-way street, with workflows being planned and optimized on the computer and then transferred to the real environment. Feedback in the other direction was nonexistent or rare. New factors affecting production operations were incorporated in the virtual model only in exceptional cases. Cyber-physical equivalence is based on a constant dialog between the real and virtual worlds, in which the physical production line and its digital equivalent melt into one. It also has the advantage of allowing manufacturing processes to be documented end-to-end in digital form and in real time.

The underlying principle of cyber-physical equivalence is that it creates a live picture of the production system, capable of delivering up-to-date information on the status of products, manufacturing resources and customer orders at any time. It helps production planners to optimize processes and make on-the-spot decisions when urgent changes are necessary. This ad-hoc approach to production planning also enables processes to be modified at short notice in order to respond flexibly to specific customer demands or avoid delivery delays due to production bottlenecks.

Landmark in the Land of Ideas 2015

The Visual Computing Research and Innovation Center is a joint undertaking by the Fraunhofer Institute for Computer Graphics Research IGD and the University of Rostock. By combining their respective skills in fundamental and applied research, the two partners are able to develop innovative solutions in the field of smart production control. The ability to manufacture short-run and personalized products cost-effectively will prepare German industry for tomorrow’s manufacturing world. It was for this reason that the project “cyber-physical equivalence – smart production control” was awarded the title of Landmark in the Land of Ideas 2015, as part of this German innovation initiative. The prize-giving ceremony took place in Rostock on November 4, 2015.