Article from Kunal Suri, researcher at CEAAleksandr Sidorenko, researcher at DFKI

Introduction to the Plug-and-Produce concept

The earliest mention of the term “Plug-and-Produce” dates back from the year 2000 when researchers from the University of Tokyo and Tsukuba University, Japan, coined this term. The latter was based on the analogy of the concept of “Plug and Play” from the world of computers and information systems.

Extremely present in various research publications and/or innovation projects funded by the European Union (such as FP7, H2020, to name just a few) in the last two decades, Plug-and-Produce has indeed been given a lot of focus.

Such initiatives envisioned to support the development of technologies and tools that would help materialise the concept of Plug-and-Produce, which aims to decrease the overall time and efforts involved in reconfiguring a manufacturing system.

The term Plug-and-Produce (also used interchangeably by some as “Plug and Work”) is defined as “the capability of a production system to automatically identify a new or modified component and to integrate it correctly into the running production process without manual efforts and changes within the design or implementation of the remaining production system“.

In the world of computers and information systems, this will be analogous to a user replacing their old USB mouse with a new one by just removing the USB head of the old one and inserting the new one in their computer and the software automatically configuring it for their use.

However, even 20 years or so after the first introduction of the idea of Plug-and-Produce, most of the reconfiguration and adaptation of the production lines/ systems in factories are done manually.

The ongoing Industry 4.0 revolution anticipates that these production lines become (semi-)automatic and self-controlled. This could be made possible by utilising the Plug-and-Produce concept in the production systems to enable it to handle new deployments introduced to the existing production line, along with its reconfiguration (or extensions). In other words, when a new machine (or a sub system) is deployed or commissioned, all its components must be brought to the production line (that is to say the existing system) mechanically, electrically and informatically in a (semi-)automatic manner in such a way that the entire system starts to operate without any external help.

How DIMOFAC will tap into Plug-and-Produce technology

The mission of the DIMOFAC project is to provide an industrial grade solution that makes the production lines on the factory shop floor easy to reconfigure. To put it differently, these production lines must be able to adapt quickly in a cost-effective way (for instance, introduction or removal of entire modules or a machine or robot, etc.) to the needs of the manufacturers.

Such a possibility is of high importance in today’s changing market dynamics (which is particularly relevant in the time of pandemic) along with an increase in the personalisation of demands by the end user. More information about the purpose of the project can be found here.

Thus, the incorporation of the Plug-and-Produce-based concepts and underlying technology will support the DIMOFAC project and its 30 European partners (along with others joining in the open calls at later stages) to achieve their mission, which is to provide an easy, efficient and cost-effective possibility for the manufacturer to reconfigure their production lines both:

  1. Physically, on the shop floor,
  2. At the level of digital implementation of their information/manufacturing system.

The implementation of Plug-and-Produce technology

In the DIMOFAC architecture a special focus has been given to the development of the reconfigurable modular cyber-physical production modules, which have Plug-and-Produce capability.

To achieve Plug-and-Produce at least two essential challenges should be addressed:

  1. Creating standardised interfaces to enable a universal connection between all components.
  2. Getting the common understanding of what components are capable of.

 There are several distinct types of interfaces, which can be identified as:

  1. Information interface or control network.
  2. Power interface to supply a machine with media (electricity, pneumatics, etc.)
  3. Mechanical interface for fixing the position of the modules.

In DIMOFAC, we determine also material transfer interface, stressing out the importance of the unified material (products, raw material) transfer between the modules. The first two interfaces can be in principle standardised and there are already some prototypes exiting for them, for example, a universal plug-in connector (see Figure 1 below).

Figure 1: Universal Plug-in Connector [Source]

Furthermore, though mechanical and product transfer interfaces are difficult to standardise, due to the high mechanical individuality of every single production system, in DIMOFAC, we assess the possibility of their unification in order to achieve high level of reconfigurability and Plug-and-Produce capability.

Another prerequisite for implementing Plug-and-Produce concept is the necessity of module’s self-description capability: the module should be able to automatically advertise its functionalities or skills. It should also describe its properties and required parameters for automatic setup. This can be achieved by the common information model (CIM), which will be elaborated in the course of the project.

As already described in a previous article, the DIMOFAC common information model is based on the concept of an Asset Administration Shell (AAS), which uniformly describes all the properties and capabilities of an asset. The asset can be a production module, but also a software entity or an operator. Thus, using the AAS as the common information model enables the universal Plug-and-Produce capability across all the DIMOFAC framework.

Finally, the integration layer of the DIMOFAC architecture will provide the needed infrastructure to enable Plug-and-Produce, that is to say an automatic discovery of each module, a capabilities registry, an orchestrator, and a messages routing system.

Industrial benefits for manufacturers

Plug-and-Produce capability is one of the vital pieces for finalising the puzzle and providing a solution to the question on how to assist the manufacturers to perform a fast and cost-effective reconfiguration of their production lines?

As aforementioned, with the use of common interfaces such as universal plug-in connectors along with providing the capabilities of self-description to the industrial modules, Plug-and-produce technology becomes a vital part of the DIMOFAC solution.  

Moreover, the incorporation of the Plug-and-Produce capabilities along with other technologies, such as Digital Twins, will in turn assist the DIMOFAC project to reach its KPIs, which are:

  • More than 20% decrease in reconfiguration time
  • At least 12.5% increase in resource efficiency
  • At least 15% reduction in overall cost of production
  • More than 10% increased yield improvement.