Engineers from the Campus of Gijón are working to perfect the manufacturing system based on 3D printing. Researchers from the areas of Engineering of Manufacturing Processes, Mechanical Engineering and Continuous Production Mechanics and Structure Theory are developing a project that aims at minimizing errors of dimension and size when 3D printing pieces and also improve their finish and surface.

The laboratories of Construction and Manufacturing Engineering have a 3D printer that was acquired with funding by the Campus of International Excellence as part of the ARS_CEI: Lab project, funded by the Subprogram of Strenghtening in 2011, to unite the world of Engineering of the Campus of Gijón with the actions that take place at the Laboral Art and Industrial Creation Center.

The so-called Additive Manufacturing (AM) has become, throughout the past decade, in the most dynamic field in terms of manufacturing processes. The appearance of new techniques, alongside the improvement of already-existing technologies, has allowed AM processes to evolve from simple applications for quick protrotyping to the direct manufacturing of completely-functional pieces and tools.

The main objective of this group is to develop techniques that lead to the improvement of the capacities of this process and the behavior in operation of pieces manufactured with AM processes.

The group of Advanced Research in Additive Manufacturing of the University of Oviedo (ARAMO) was created in 2011 as the result of the collaboration between the Area of Manufacturing Process Engineering and the Area of Mechanical Engineering of the University of Oviedo. The main objective of this group is to develop techniques that lead to the improvement of the capacities of this process and the behavior in operation of pieces manufactured with AM processes. The base philosophy of ARAMO involves a multi-disciplinary approach, making it a cross-curricular group, open to collaborating with researchers inside and outside the institution.

Their first published research, Dimensional accuracy improvement of FDM square cross-section parts using artificial neural networks and an optimization algorithm - Int J Adv Manuf Technol (2013), dealt with the improvement of the dimensional precision of the pieces manufactured via Fused Deposition Modeling (FDM). The lack of precision in the manufacturing of this type of pieces is a key aspect in relation to the execution of elements with industrial purposes.

The nut of a cap

The research team became aware of this problem due to the complications that arose in the manufacturing of a prototype for a modular bottle. Said bottle, designed as part of an Undergraduate Thesis, had an external nut in the neck and an internal nut in a cavity at the base. Although the design incorporated the tolerances needed for both nuts to fit properly, the lack of precision of the FDM system prevent this from being possible in the first version of the prototype. Based on the experience acquired, both geometric characteristics were redesigned, which lead to a functional prototype.

As a consequence of this situation, a project was set in motion with the aim of characterizing the natural dimensional deviation of the manufactured pieces and to apply techniques based on Artificial Neural Networks (ANN) and Evolutive Algorithms (EA) to modify the design of the pieces. This project achieved a reduction of almost 50% in the dimensional error related to the distance between parallel faces of the piece.

Currently, ARAMO is conducting several simultaneous researches in order to delve into the improvement of the quality of the pieces manufactured with AM. These researches pursuit the characterization of the processing capacities and dimensional optimization of the pieces, as well as the characterization of their mechanical properties and their superficial quality. Their work is focused on the FMD and Polyjet processes (based on the projection and maturing by UV radiation of photopolymers).

In the future, ARAMO has set its aims in expanding the improvement of processes through the redesign of the mechanical configuration of the systems and the development and establishment of improvements on the lesser-known processes.

Research Team

• David Blanco (Area of Engineering of Manufacturing Processes)
• Braulio J. Álvarez (Area of Engineering of Manufacturing Processes)
• Alvaro Noriega (Area of Mechanical Engineering)
• Alberto García (Area of Mechanical Engineering)
• Pelayo Fernández (Area of Continuous Production Mechanics and Structure Theory)