Digital twin systems – the key concept for Industrie 4.0

Digital twin systems comprise the entire infrastructure, tools and processes used to create, manage and utilize digital twins. These systems are designed to collect real-time data from physical assets, update digital twin models, perform analyses, simulations, optimizations or other calculations, and provide insights and control of physical assets or processes.

The concept of the digital twin stands for the possibility of modeling products, machines and their components with the help of digital tools, including all geometry, kinematics and logic data. A digital twin is the image of the physical asset in the real factory and allows it to be simulated, controlled and improved.  

Partial models of a digital twin

From a manufacturing and engineering perspective, it is evident that digital twins require and cover a number of different aspects, such as

• Model-based self-description using unique attributes and parameters describing configuration data, e.g. for auto-identification, to connect machines and components easily to MES and other Industrial IoT-solutions
• Description of skills, including parts of the control code with the result that an assembly of components and their respective control logic elements fit into a running control program. This creates a PLUGandWORK environment where new components can be plugged in at runtime and integrated automatically on a functional level.
• Models of the correct runtime behavior of a machine, a line or an entire manufacturing shop, based on learned data from machine learning.
• An extremely wide range of offline- and online-simulations, such as finite element simulations, virtual commissioning or physics simulations in which the manufactured goods interact with the machine kinematics. Ideally, the various simulation models should be able to interact in order to generate an integrated simulation model. Up until now, the digital twin has been used primarily in the context of simulation; as we point out here, this definition is much too narrow.
• A digital factory describing machines and other manufacturing resources, buildings and utilities. A building information model (BIM) might also be part of a digital twin as long as it contains relevant information, e.g. topology. The concept of digital factories already has a long history and is described by well-known standards, such as VDI 4499.
• Services that a cyber-physical component offers to its users.
• IT security, access rights, handling of certificates, version management and compatibility checks of different versions of digital twins.

Digital twins are essential for Industrie 4.0 and the digitization of manufacturing. Their content is key during all stages of the life cycle and within different types of platforms and tools, from engineering to after sales services.  

Digital twins are essential for Industry 4.0 and the digitalization of manufacturing. Their content is created in the various life cycle phases of a product or factory, using different tools on different platforms.