Improving quality control in 3D printing: a method for G-code-based geometry reconstruction in material extrusion

Additive Manufacturing (AM) enables the creation of complex structures through a layer-by-layer material deposition process, offering significant advantages over traditional subtractive manufacturing. Among the various AM technologies, Material Extrusion (MEX), also known as Fused Deposition Modelling (FDM), is widely used due to its low cost and simplicity. This paper presents the development of an algorithm to reconstruct the sliced geometry from G-code in MEX processes, addressing the need for accurate representation and analysis of printed parts. The implemented algorithm (by MATLAB) interprets G-code commands to recreate the 3D structure of the part, allowing to view and verify the nozzle path, optimise printing parameters, and check the quality. Furthermore, the algorithm facilitates comparative analysis with the original 3D model, identifies potential issues, and implements the mechanical properties prediction by converting the G-code into a fine STL file. The algorithm’s output provides valuable insights into the internal structure, showing material distribution and void presence, supporting further research and industrial applications. This advancement significantly contributes to the digital process chain in AM, aligning with the goals of Industry 5.0 by promoting an integration from design to process control.