Image-based 3D Scanning: System Setup and Operations for Two Different Model Approaches

Abstract

3Dmodels are required for design studies carried on in many sectors such asautomotive, machinery, aeronautics and industrial design. 3D models frequentlyused in Computer Aided Engineering (CAE) applications are obtained by drawingwith a Computer Aided Design (CAD) software. Moreover, when it is desired toimprove the design of an existing part or to make its computerized analyzes, itis necessary to transferred to the electronic environment. Today, 3D scanningmethods are used especially in reverse engineering applications,patient-specific designs, cases that parts need to be redrawn and obtainingfree-form models. The use of different 3D scanning methods, such as laserscanning and optical scanning, is increasing in scientific studies andindustrial applications. In addition to these methods, the image-based 3Dscanning method known as a low-cost photogrammetry method has started to beused in many different areas such as engineering, biomedical, forensic medicineand archeology. It is possible to carry out the digitization process with thismethod which basically needs a photographic machine and a computer softwarewhich allows the creation of the 3D model from the obtained images. During thisprocess, some problems arise from the operator and external factors, and as aresult, the scanned models cannot be digitized as desired. In this study,image-based 3D scanning process is explained in detail and two differentapproaches which can work manually and reduce errors caused by operator andexternal factors that may occur in the scanning process are discussed. Inaddition, image-based 3D scanning applications for both systems were carriedout and merits and shortcomings of these systems were evaluated and comparedthe methods used in these systems with other scanning methods.