Development of a digital twin for additive manufacturing

Since the first industrial revolution that companies have been looking to produce more, cheaper and better products. Nowadays, this quest has achieved a new dimension due to the high market competitiveness. Moreover, is also possible to notice an improvement of the quality standards associated with the manufacturing technologies. Both quests have increased demand for new production technologies that are more efficient and sustainable than the technologies they replace. Leading to a continuous need to develop new technologies, improve existing solutions or even merge existing technologies into a single process to reduce intermediate stages during production of new products, reducing the production time of the products. In recent years, one of the production technologies that has seen a great increase in popularity, and therefore in new developments are the additive manufacturing (AM) processes. This increase in popularity is due to some major aspects, in first place is the fact that AM generates less raw material waste during production that traditional solutions, in some cases the raw material waste is almost zero. In the other hand it also allows for a greater flexibility and continuous change of the production design since it does require fewer, or even no tools, to assist the production, especially AM based on powder bed fusion (PBF). From a macroscopic perspective, manufacturing technologies need to be able to produce faster, in a more dynamic way and ensuring the quality standards are maintained, represent the fundamental needs for any institution. In order to provide solutions to the previous desired form the industrial stakeholders have been developing the concept of the industry 4.0 and Internet of Things (IoT). These solutions allow for a constant communication between the machines, resulting in a more efficient and control production cycle. However, this objective represents an exhaustive task due to a great variety of problems, ranging from interoperability, communications issues to equipment compliance to data-driven paradigm. To increase the implementation scope of this paper, will be provided some development and contribution in terms of information modelling in the additive manufacturing area. Therefore, will be analyzed the fundamental aspects for developing a digital twin of the optical system of a PBF machine. Moreover, will be applied the concept of a digital twin to the laser source and to the galvanometric scanner. This process is fundamental for integrating IoT information modelling into additive manufacturing solutions. In the other hand, it will be analyzed how technical information is generated during the process and how this data can be later used for developing a digital twin that is able to connect IoT devices integrating an AM system. After a more theorical analysis is preformed will be presented a simplified prototype unit to test the implementation of the proposed system.