Using 3D Game Engines to Build Digital Twins for Industrial Machine Simulation and Testing

Developing control software for
industrial machines requires careful planning.
However, it is still crucial to test the software before
deploying it on a physical machine. To create
meaningful tests, a digital twin that can simulate the
behavior of the real machine is required. Yet, creating
such digital twins can be both costly and complex –
and often, they still fall short when it comes to offering
realism. In light of these challenges, AVM
Engineering AG approached us with the task of
evaluating whether modern game engines are
suitable for developing digital twins of their industrial
systems. Our objective was to design a workflow for
creating such digital twins and to demonstrate it using
parts of a package distribution machine.

Research into digital twins
and 3D simulation highlighted the potential game
engines provide with their advanced physical
simulation capabilities. To determine the most
suitable platform for implementing digital twins, we
analyzed and compared the leading game engines –
Unity and Unreal Engine 5. Based on performance,
visual fidelity, extensibility, and licensing terms, we
chose Unreal Engine 5. For reliable and standardized
data exchange with industrial equipment, we used
OPC UA, the de facto communication standard in
industrial automation.

To enable communication between Unreal Engine 5
and industrial controllers, we required a bridge
between the OPC UA server and the game engine.
For this, we integrated open62541, an open-source
OPC UA implementation in C, into the game engine.
To simplify the communication with the server we
created custom Blueprint functions, the visual
scripting language of Unreal Engine, for a simple
drag-and-drop experience when building a digital
twin. These building blocks enable read, write and
subscribe operations from the game engine to the
OPC UA server. In addition, we investigated the
process of converting existing CAD models into
assets suitable for use in Unreal Engine 5. This
allows for highly realistic representations of industrial
components within the digital twin.

The integration of modern game engine
technology with industrial automation tools enables
the creation of highly customized digital twins. In this
case, it allowed for a real-time simulation of the
control logic developed for the package distribution
machine, providing a safe and efficient environment
to test and validate the software under realistic
operating conditions—without the need for the
physical system.
To showcase the capabilities of our Blueprint
functions and to make our approach to digital twin
development more accessible, we designed and
implemented custom models inside Unreal Engine 5.

These models were specifically created to replicate
key elements of the package distribution
system—most notably, the conveyor belt mechanism.
The components not only illustrate common use
cases when it comes to OPC UA communication but
also incorporate realistic physics simulations to
closely mimic real-world behavior. User testing
confirmed that our construction-based approach is
intuitive and effective, significantly supporting the
understanding and development of digital twins for
complex systems.