The machine operates before set up
Virtual commissioning is an instrument for modelling digital twins of complex systems and testing and optimizing functions virtually. Even before the first machine part is installed, the digital simulation provides a precise picture of the real processes of a planned system. At PIA Automation, our specialists, including Markus Krempl, Coordinator Virtual Commissioning, and Sven Suklitsch, Lead Simulation, have implemented this concept. The two experts provide insights into their first customer projects with virtual commissioning.
When did PIA Automation use virtual commissioning for the first time?
Suklitsch: We have been working on this topic since 2016 and have carried out fundamental preliminary work in the form of dissertations and test projects during this time. Based on these results, we implemented our first customer project in September 2023.
Krempl: This first application was the pilot project, and since then we have been offering our customers virtual commissioning in new projects.
What was the first project about?
Krempl: The objective was to convert an existing system. We had built the system and the customer had done the programming himself. However, the system did not achieve the desired output due to changes in the peripheral operations.
Suklitsch: That's why the customer approached us and was looking for a solution. Because we had the detailed engineering data for the system, we analyzed the problems and suggested reprogramming it.
Krempl: Given the conditions, we were able to offer the customer the option of modeling the modified system as a digital twin first. This meant that we were able to test the new programming virtually before proceeding with the physical conversion. Without prior modeling, the conversion of such a system would have caused around nine weeks of downtime. Thanks to virtual commissioning, we reduced the downtime to four weeks, saving our customer more than 50 percent of the time.
How do you create a digital twin?
Suklitsch: We actually start as we do with every design. Often with a hand-drawn sketch, which is transferred to a 3D model and the milestones for building the machine are run through. The modeling of the digital twin begins after the design freeze, i.e. the time after which major changes are only possible in compelling cases. Once the design has been defined, we create a kinematic model of the machine, an intelligent 3D model, so to speak. It contains all moving parts and their axes, the sensors and the material flow in production. The second part of the modeling is to program a behavioral model for the individual field devices.
Krempl: That's my part. Sven Suklitsch and I work hand in hand on a digital twin. Once his team has programmed the kinematic model, we start working on the behavioral model. It describes what the machine actually does. This is defined by the control system. So, we program behavioral models that behave exactly like the real machine or like components that are manufactured in the machine. All of this is also done in 3D modeling.
How abstract or concrete are the visualizations of these models?
Krempl: Basically, our visualization options go into considerable detail. For example, the models depict every sensor and every actuator. Where this level of detail is not required, such as for transfer routes, the models can be kept more abstract in order to save data capacities. A 2D representation is then also sufficient.
At what point in the system development phase do you start preparing for virtual commissioning?
Suklitsch: The engineering, i.e. the planning of the mechanical and electrical parts of a system, is still identical to classic mechanical engineering. We then start modeling at the same time as the procurement phase. Procurement takes an average of eight weeks in our industry but can take up to 30 weeks for long-running systems. We use this time to model the system, develop the software on the digital twin and emulate processes - until we finally reach virtual commissioning. We already achieve a very high level of software quality in the period from the start of procurement to the first installation at our premises. We have already tested the system virtually down to the last detail before we install it at our customer's premises. During ramp-up and acceptance at the customer's premises, we can then focus entirely on process-related issues together with the customer.
When we talk about digitalization, the focus is on objectives such as increased efficiency and higher quality, but also on the potential to reduce costs. Can you quantify the cost benefits for your customers?
Suklitsch: This is the question we are often asked. However, there is no one-size-fits-all answer - but there are many examples where costs can be avoided. The faster project throughput not only saves time, but also costs. The high software quality at an early stage of development and the highly detailed modeling avoid errors that are much more expensive to correct at a later stage. Ideally, we can make necessary changes during the procurement phase and avoid bad investments.
Krempl: From my experience of installing and supporting customer systems on site, I would like to add one important point: Virtual commissioning offers our customers the opportunity to get to know their assembly line much earlier. We talk to maintenance staff and plant operators about operating or batch concepts even before the physical plant exists. Without the digital model, such questions often only arise during actual commissioning. If our teams only develop solutions on site, it is much more expensive for our customers because, for example, hotel costs and other expenses are incurred. And not to forget: By testing our systems virtually, customers save on many prototype components that would otherwise have to be produced during tests in the real machine.
What attracts customers to develop a system with virtual commissioning together with PIA Automation?
Krempl: We offer a very high level of detail. Our simulations can be transferred 1:1 to the real system. We put the material flow and all connected systems into operation in the virtual model and can also integrate our customers' existing control systems into our program.
Suklitsch: For example, our emulations of the PLC and the robot controller correspond to the real programs down to the last detail and can be used directly for the system. Furthermore, we are not restricted to specific tools. We can integrate practically any of our customers' existing software into the modeling. Finally, we provide customers with everything from a single source: system design, programming and virtual commissioning.
Do you want to define virtual commissioning as standard for new customer projects?
Krempl: We will offer this tool to our customers across the board in future. It is advantageous for everyone involved: we can increase our quality with virtualization, our customers benefit from time and cost advantages. Problems in the system concept can be identified and rectified at an early stage, long before bad investments are made in the actual implementation or expensive corrections become necessary.
Suklitsch: I would like to add two more aspects, rather softer factors: by testing systems and the components they produce in the virtual world, virtual commissioning also contributes to sustainability. Fewer real prototype parts mean a smaller CO2 footprint for our customers and for us. The fact that our teams spend less time on site commissioning a customer system at the end of a project is not just a cost factor. Being on the road less means that our employees can spend more time with their families. Ultimately, this also enhances the attractiveness of PIA Automation as an employer.