How to validate machines with virtual commissioning

Virtual commissioning begins with a vision of the desired machine behavior and sequence of operation

By Bill Davis September 3, 2020

Industrial machinery end users want customized products delivered quickly. Meeting this demand requires machine designs to be sophisticated. This need for high-level customization with greater machine complexity drives manufacturers to support a global machine design to implement manufacturing strategies. Manufacturers can enhance their machine validating process with virtual commissioning, thus meeting complex customer demands quickly, efficiently and cost-effectively. This process builds on innovative trends to create superior customer service and revenue streams with new business models.

Virtual commissioning definition

Virtual machine simulation and commissioning is the process of validating the software code for programmable logic controllers (PLCs), human-machine interfaces (HMI) and supervisory control and data acquisition (SCADA) equipment in the virtual world before deploying it on the factory floor.

As software is driving machines, its complexity is increasing significantly. It is essential to simulate the code running on a machine’s virtual twin to generate substantial dividends in time and resources. Virtual commissioning validates the PLC software in a managed environment, an integral part of the modular product development strategy. Machine builders can perform the simulation upfront and link the software to the modules, combining the final code seamlessly on an individual customer-specific machine.

Financially, virtual commissioning and visualization pay enormous dividends for companies. No one purchases a machine sight unseen. Also, they will not buy it merely because it has been virtually simulated by running software code. Therefore, users need to substantiate that a machine works before shipping it to their plant.

However, because many software integrations and safety factors are necessary to run a machine, it is critical to test it with users physically present. Hence, virtual commissioning is ideal for turning a machine on and performing real commissioning. There is less pressure for both the machine builder and its customers/users. It collaborates the engineering upfront in the design process to further reinforce the interdependency of all the disciplines involved in virtual commissioning.

Virtual commissioning essentials

Critical elements of the virtual commissioning process include:

Upfront automation linked to machine behavior: Virtual commissioning begins with a vision of the desired machine behavior and sequence of operation. Ideally, a systems model would define the machine behavior in electrical and fluids domains. A physics-based kinematic model is a good beginning by introducing forces on sliding or rotating components at different times, providing a good visualization tool to communicate between the mechanical, electrical and controls engineers. It’s also an excellent tool for demonstrating machine behavior to users.

The behavior model drives code generation: The machine behavior model (a physical demonstration of the machine operation sequence) identifies the logical devices in the design attributes critical to the PLC and HMI code development. Consider a motor with an integral encoder. The visual behavior model describes a process where the motor is energized for a certain number of rotations, stops and then reverses. The PLC code must know essential information about the motor/encoder and the expectations for use in the application. Possessing vital information in the mechatronic model provides for managing it more efficiently.

Closed-loop feedback visualization: The upfront simulation of the desired machine behavior is only valuable when validated after the finished code loads into a virtual PLC, showing machine operation in the digital twin when driven by the code, not the predictive machine behavior model.

User experience implementation: The user experience is vital to the virtual commissioning process. It shows how the digital twin demonstrates the machine’s response to user-initiated commands — for example, indicating that the operating parameters display appropriately on the HMI and whether the touchscreen and other interface devices operate correctly. Also, the virtual machine must respond correctly during an e-stop or normal shutdown and simulate faults and other use cases where safety is a concern.

Benefits and challenges

The demand for virtual commissioning, in conjunction with the digital twin, provides the following advantages:

  • Compressing time: Caters to users who are continually changing their tastes quickly and driving a reciprocal need to respond rapidly.
  • Saving costs: Reduces time to debug the design and its associated controls physically.
  • Minimizing risk: Provides virtual testing, so evolutions present theoretical issues, with no PLC program problems.

Virtual commissioning benefits create efficiency on the shop floor, achieving higher speeds with reliability — a potential 20% improvement in the capacity of a machine shop or operations. This efficiency saves valuable time previously spent in physical validation, verification and commissioning (see Figure 1).

However, the upside of innovative technologies come with their accompanying challenges:

  • Validating third-party equipment integration requires the need to bring disparate systems and code together cohesively.
  • Robotic integrations require connecting robotic code into the PLC to increase efficiency.
  • Logistics automation provides significant proficiency only by orchestrating multiple interfaces simultaneously.

Many use cases tout the benefits of virtual commissioning. Consider two companies who are witnessing notable improvements.

Successfully using virtual commissioning

Tronrud Engineering is a prime example of effectively using virtual commissioning. Tronrud develops, manufactures and supplies innovative machines and equipment to users. Using a new machine’s digital twin allows the designers, engineers and programmers to work simultaneously while continuously sharing their knowledge (see Figure 2). This process significantly compresses commissioning and engineering time.

“By working on the design, mechanical components and programming simultaneously, we can drastically reduce the time to market. In another project, this approach allowed us to save about 20% or two months,” said Erik Hjertaas, general manager packaging technology at Tronrud Engineering.

In response to the parallel execution of development steps in an interdisciplinary team, Tor Morten Stadum, PLM manager at Tronrud Engineering, said, “We shortened the design phase by about 10% and commissioning by 20% to 25%.”

Eisenmann, a Germany-based global provider of industrial solutions, plans and builds made-to-measure manufacturing, assembly and enterprises throughout the world. They have deployed highly flexible distribution plants that are energy- and resource-efficient for more than 65 years. They’re reaping the many benefits of virtual modeling, simulation and commissioning.

“The simulation model we create with plant simulation is often part of the deliverable to our customers. Many of them also use plant simulation themselves, so they know how to run the simulation and change the needed parameters. This is a big benefit for them because they get a virtual model of the physical line,” said Dr. Heiner Träuble, simulation expert automotive paint systems Eisenmann.

“We are very pleased with the discrete event simulation capabilities we have developed in Eisenmann throughout the years, especially our use of Plant Simulation,” said Sebastiano Sardo, senior vice president, Eisenmann Conveyor Systems.

Adapting machines for the future

Manufacturers must consider current trends and adapt to changing consumer preferences to build flexible machines that address a full range of products. Flexibility must be built into the machine software to respond to the changing needs of the customers.

Using the Xcelerator portfolio, a suite of services from Siemens Digital Industries helps manufacturers create a comprehensive digital twin. It also integrates simulation within the machine design to be flexible, capable and adaptable. Connected machines, which can communicate with other machines, extend their capabilities through software-driven changes. This value is essential for modern manufacturers to maximize the productivity of the end-user environment.

Companies need a digital solution that crosses all aspects of a machine manufacturer’s product and production process to connect, adapt, predict and extend the machines of tomorrow, today.

Author Bio: Bill Davis is the solution director for the industrial machinery and heavy equipment industry for Siemens Digital Industries Software. His experience and insights have been acquired from a career spanning 30 years in engineering and operations management with machinery and heavy equipment companies. He has a master’s degree in business administration from Marquette University, with a concentration in operations management and strategic marketing, as well as a BSME from Milwaukee School of Engineering.