PLM Digital Twin applications

A crucial aspect in the product design and realization is the planning phase of the product lifecycle. The product lifecycle management concern the process of conceptualization, design, procurement, manufacturing to use and recycle of the product. As it can be seen in Figure 18 each PLM phase involves an extensive data generation. Nowadays according to (Tao, 2018) it resembles that data gathered during each phase of the PLM are stagnant, isolated and fragmented. Data are not complementary in each phase of PLM, interoperability among systems and the data structure is not assured. The data integration and the interaction between systems it is considered by the most the new main asset over which leverage new value creation.

Another crucial gap still existing in the PLM regards the distance between the physical and the virtual dimension of the product. The actual PLM research focuses on the physical product rather than on the virtual one. Furthermore, the keeping track of the actual demand and immediately reshape design and manufacturing of new products still remain an obstacle in the PLM.

Figure 18: Product lifecycle phases data scheme, source (Tao, 2018)

The Digital Twin intervene in the PLM as a possible solution with the intention to address the topics discussed in this section. But in which context of the PLM the Digital Twin can be influent?

1. Digital Twin in product design:

The focus on the design phase of the product lifecycle involve the application of the digital twin in 3 distinctive phases according to (Tao, 2018)

• Conceptual Design: is the first step of the product design phase and deals with the idealization of the aesthetics features and the main function of the product. The Digital Twin offers support to designers in collecting and presenting all data needed to implement the desired features requested by the market through the integration of customer satisfaction, product sales, product competitiveness, investment plans, and many other data. In addition, another crucial aspect regards the communication between the customers and client. The match of the desired product with the customer requirements is reinforced by real time exchange of information which facilitate product development refinement and a rapid time to market. The customer could participate to the design conceptualization phase enhancing his/her final satisfaction and reducing time and material consumption

• Detailed Design: thereafter the concept designs the designers has to complete product prototype and the development of the necessary tools and equipment and begin with the test phase. The Digital Twin offers advantageous aspects in the test phase, thanks to simulation environment proposed it enables product configuration and parameters tuning as well as by offering an accurate storage of historical data that avoid configuration repetition and optimize the source of possible new test.

• Virtual Verification: the last phase of product design usually foresees the validation of the test executed by pushing in production a small batch of product that can be eligible to validate what has been achieved until that moment. Often this approach requires repetition of small batch production lengthening the time to market and wasting material, machine time and labor time. Thanks to the digital twin this last design phase can be

transferred to a simulation performances environment which ensure to predict the potential performances of the design achieved.

Figure 19: Digital twin-based product design, source (Tao, 2018)

2. Digital Twin product manufacturing:

the product manufacturing entails each phase able to transform a raw material in a finished product. To sum up the main activities involved in this process can be cited:

• resource management

• production plan

• process control

To foster each activity a well-organized structure, empower the correct fulfilment of the entire product manufacturing. The Digital Twin solution, according to (Tao, 2018) proposed a structure called DTS, Digital Twin Shop Floor. This structure combines three dimension that follow the entire manufacturing procedures for each activity previously described, by the integration of Physical Space, the PS “Physical Shop Floor”, a pure Virtual information space, the VS “Virtual Shop Floor” and an interconnection space of the last two, the SSS “Shop floor Service System”, converge. The nature of the convergence determines the added value of this model which is enabled by its constituent the SDTD “Shop Floor Digital Twin Data”.

The tasks to be executed, foreseen by the production plan, are simulated in the VS where optimization algorithm process data coming from PS. The results of optimization are further processed by the integrated software systems, such as MES, PLM, ERP, CRM and each other management software at disposal of the SSS, where resource management and process control optimize with attention the data provided. The execution tasks are communicated to PS to be executed. The iterative production process aims to be guarantee process control and maximization of the production capacity by the deployment of Real time data

Figure 20: composition and operations mechanism of DTS, source (Tao, 2018)

A practical example of DTS is offered in

Figure 21 with regards to the production of steel bars. The RFID tags on the bars allow the bars tracking which can be elaborated by CNC machine. The CNC machines are connected through the enterprise network and can continuously transmit real time production data. The data received can be processed and simulated by the VS, which starts optimization. The integration with SSS supported by the information systems (ERP, MES, PLM) allows an enhanced process control and support for the operator in taking equipment decision or machine production plan.

Figure 21: The drive shaft manufacturing based on digital twin, source (Tao, 2018)

3. Digital Twin product service:

A further implementation in the product lifecycle refers to the after-sale services. In Figure 22, it is proposed by (Tao, 2018) a summarized version of potential services enabled by the Digital Twin solutions. The main groups of after sales services can be grouped in:

• User support: management of user’s behavior data reinforced by analysis, allow new potential service in user’s monitoring and creation of operations guide. This last topic is empowered by the real time data elaboration, as matter of fact operative suggestion to operators, could be seen as a crucial aspect not only for production but also for operator’s security

• Maintenance and product failure

• Optimization of productive systems

• Energy consumption and savings

Figure 22: Digital twin-driven product service, source (Tao, 2018)