EFFECT OF DIGITIZATION PARAMETERS ON FREEFORM RUNNER MEASUREMENT APPLYING FACTORIAL DESIGN
Antonio Piratelli-Filho1; Lucas Peres dos Reis1; Rosenda Valdés Arencibia2
1 Universidade de Brasília, UnB, Faculdade de Tecnologia, Depto. Engenharia Mecânica; 2 Universidade Federal de Uberlândia, UFU, Faculdade de Engenharia Mecânica
doi:10.20906/CPS/COB-2015-1992
Resumo
This work proposes an approach to optimize the selection of the digitization parameters of a freeform jet ski aluminium runner. The experimental approach involved the selection of variables and levels based on software ScanStudioHD, used to carry out measurements with the laser scanner 3D NextEngine. Firstly, the part was coated with special powder to take measurements with an Articulated Arm Coordinate Measuring Machine (AACMM) and the determined data points were fitted to a Non-Uniform Rational B-Spline (NURBS) using Rhinoceros software. The resultant Computer-Aided Design (CAD) model was considered as reference. Secondly, the same coated part was digitized with the NextEngine scanner to capture the cloud of points at each experimental condition and to compare with the reference CAD model with Rhinoceros software, determining the deviations. The variables selected to investigate were the scan type (A), the number of points (B) and the target (C), adopted with number of levels 3, 3 and 2, respectively. A Factorial design was built and the number of experimental runs was 18. The runs were performed in random order, with the part positioned at a fixed distance from the laser source (Wide). The mean (M), the standard deviation (SD) and the scanning time (ST) were determined in each run (response variables) and the Analysis of variance (ANOVA) was applied to find the statistically significant variables with levels to minimize the response. The use of factorial design proved suitable to reduce the variability of the deviations and scanning time in the digitization process.
Palavras-chave: jet ski runner; analysis of deviations; design of experiments