Investigating Alignment Effect on Inspection Accuracy of AM Part Using 3D Scanner

Abstract

Presently, parts having intricate custom-made profiles are mostly fabricated using additive manufacturing (AM) processes. It becomes an essential task to verify the accuracy of AM parts so that they meet customer’s need and requirement. In product quality control, quick error comparison of manufactured part and an original CAD model is usually laborious but still a critical issue. Noncontact inspections using 3D scanners were preferred over conventional coordinate measurements, due to the significant amount of point data capturing in very short span of time. One of the important step of the noncontact inspection procedure using the 3D scanner is the correct localization of the datum reference frame. This step would help in the effective alignment of the digitized point data. This paper takes into consideration various 3-2-1 alignment approaches and investigates their influence on the inspection results. The result provides an evidence that an incorrect description of the product reference frame can lead to erroneous estimation of actual part deviations. The results show higher distance distribution for most of the point data of third alignment as the distance distribution is influenced by the worst description of the part reference frame. On the contrary, second alignment shows least distance distribution among point data due to correct reference frame definition.