Optimization of positioning system of FDM machine design using analytical approach

Purpose - The purpose of this paper is to analyse the conception of the positioning system of fused deposition modeling (FDM) machines, optimising design parameter and components accuracy to decrease mechanical errors of equipment, which, consequently, results in the increase of parts accuracy. This paper also reports studies related to analytical estimation of machine errors, describing a theoretical model which was used for the multivariable study. Additionally, an alternative conception is proposed, according with the result of this study. Design/methodology/approach - For elaboration of the numerical model of equipment, the authors have focused on conception of first generation of FDM, specifying as design parameters, timing belt stiffness, linear bearing clearance, and accuracy grade of ball screw housing, support and pulley. In order to identify the main effect of each design parameter for the final error of machine, the authors have applied a multivariable method in addition to identifying the error budget of model. Also indicated are the two factors that promote more errors, undergoing a proposal of conception which consists in replacing one component of machine. Findings - With reference to the evaluation of the numerical model, equivalency was found between the resultant error of model and the current FDM accuracy. The result of multivariable study identified the main causes of errors in machine, implying on an optimized solution which decreases the initial error in 69 mu m. Similarly, the evaluation of the proposed conception resulted in the reduction of general error in almost 20 mu m, even though the worst case was studied for this comparison. Originality/value - Although the number of applications for additive manufacturing has been growing in recent years, implying an increase of demand for high precision parts, there are still several challenges to be overcome, such as the improvement of equipment. For that reason, the motivation of this work concerns the contribution for development of new equipment, as well the improvement of current technologies. Furthermore, the authors' focus was the reduction of mechanical errors through an analytical approach.