Article - An essay in the management myths series!

Digital Twin - what is it?

Industry 4.0, the Digital Twin of manufacturing - we often hear these words, but what are they.

Let's start with Industry 4.0 because it is from it that the Digital Twin originated. Industry 4.0 is, in short, automation and robotization, or the replacement of human labor by machines, or you could say optimization of production, or lowering the cost of production. When thinking about automation and robotization in the context of Industry 4.0, we should not concert only on manufacturing. Automation and robotization, understood as digitization, for example, can also be introduced in typical office departments. Industry 4.0 is robots working in production, but Industry 4.0 is also a customer service bot or an automated customer order processing system. Automation, robotization or digitization is a good thing for industry, it should reduce the cost of production, operation of the company. However, it is worth bearing in mind that there are technological limitations. So, not everywhere and not always there is a technological possibility to automate, robotize something. Perhaps such a possibility exists, but it is very costly and not economically justified. So the decision to automate and robotize needs to be reasonably considered.

Automation, robotization, digitization allowed Digital Twins to come into existence. We distinguish between two Digital Twins, which differ significantly in functionality, that is, offline and online Digital Twins. In general, a Digital Twin is a representation of a factory in the virtual world. Today's technology makes it possible to build a 3d virtual world. This means that a Digital Twin of a factory is a factory mapped in the digital world, in a 3d model. The mapping includes the work of machines, people, transport routes, inter-station and warehouse inventories. So in Digital Twin we can see the work of our machines, the work of our crew, just like in a computer game. Digital Twin also means that we can run simulations without consequences for the real world. We can test in the digital model any scenario (change of workstations, operation of machines, transport routes, etc.) and when such a scenario works out implement it in real production, and when it doesn't work out - we lose nothing. As mentioned above, we distinguish between two types of Digital Twins, the distinguishing criterion is the source of the data.

Online Digital Twin - supported by companies such as Siemens, based on reading data from machines and showing in the digital world the real operation of the machine based on online data from machines. This type of digital twin perfectly illustrates downtime, congestion on machines, but requires machines capable of communicating with the software. The advantage of such a Twin is the timeliness of data, current information about the operation of machines. The disadvantage is not recognizing what the worker is doing between the bars of the machine.

Off-line Digital Twin - supported by companies such as FlexSim, based on collected data from production. Data collection is done by observing workers' work and, if possible, by reading data from machines. Based on this data, a digital model of the company is built, i.e. the work of people and the work of machines. In this model it is very important to map the work of people between the bars of the machine. The advantage of such a Digital Twin is the ability to analyze the work of people (e.g. identifying apparent work) and to simulate changes in this work (reorganization of the workstation, transport routes). No infrastructure is required to build such a model. The disadvantage is that the model is not online only a record of the observed situation on production (e.g. one day, one week). This is also an advantage, because we can stop this digital model and scroll back and forth at times, checking how the product is affected by the changes we make. With today's technology, only this type of Digital Twin allows us to optimize production, human labor, reduce production costs (machine labor can simulate both types of Digital Twin).

Advantages of building a Digital Twin

  • Online Digital Twin, thanks to access to live data from machines, will make visible downtimes, breakdowns, allow to measure and manage the real performance of machines.

  • Off-line Digital Twin thanks to observing and measuring the work of people and machines allows you to achieve savings in human labor (including the elimination of walking, sham activities). It gives the opportunity to optimize production by simulating changes in the organization of work, layout of workstations in order to more fully utilize the work of people and machines and at the same time reduce the cost of production.

At our company (BPI), we build an offline Digital Twin for clients. We use LogABS software on the FlexSim engine. LogABS is an overlay on FexSim that simplifies the way we build the Digital Twin model. With it, we are able to build the Digital Twin model quickly, and we can run simulations on it just as quickly for production changes. Fast also means lower costs for our work. With the help of the Digital Twin, we can simulate changes: organically human labor (reducing the composition of the crew) reducing walking time (distance), increasing automation and robotization. Already in many companies with the use of the Digital Twin we have optimized production, by speeding up changeovers or identifying wasted time or reducing the number of employees we reduce the cost of production in amounts of about PLN 1million per year.

For those interested in how the Digital Twin that we are building works, please visit our You Tube channel: https://youtube.com/playlist?list=PLPVgpJtoRcyFeF6ZwdfMjAvL1WnvvMwXc

Or on the website to the example tab: Case study