Application of the TOPSIS decision-making method for selecting a manufacturing technique for children’s furniture elements with therapeutic functions

Making furniture or furniture elements that account for the needs of children at various stages of development or with psychomotor dysfunctions is very difficult. From the point of view of exploitation and production technology, it is difficult to select a specific material and manufacturing technique. In this article, the results of using the APEKS method, which is a type of Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) method, are presented to select the best solution for the production of children’s furniture elements with surface structures similar to those of natural materials. Wood bark was selected as a material that, due to the sensory tactile sensations of dysfunctional children, could contribute to therapy and education. Comparative analysis was performed on the basis of the subtractive and additive methods used for manufacturing furniture products. Precise multiaxis milling of ash wood and 3D printing with fused filament fabrication technology using wood PLA filaments were carried out. The method used to select the best option considered quantitative and qualitative criteria in the assessment. Various parameters characterizing the surfaces were analyzed, such as geometric dimensions, hill heights, valley depths, and 3D surface parameters. The quality and surface roughness (Sa, Sz, Ssk, Sku, Sp, and Sv) parameters obtained based on 3D microscope measurements were determined. A scale of 1 to 10 was used to assess qualitative factors (i.e., usability and aesthetics). Based on the critical values obtained from the coefficient K_cri = 79.36, it was assumed that multiaxis wood milling was the best method for producing furniture elements with the required surface characteristics for use as therapeutic and educational tools for children with dysfunctions. The applied method allowed an effective evaluation of the compared variants of the production of furniture elements for customized applications.