Regional Symmetry of the Pelvis

Understanding the left-right symmetry of the pelvis can assist with the virtual reconstruction of fractured pelvises in the future. Further specifying the different regions can give more information regarding the anatomy of the bone. CT scans of intact pelvises are turned into 3D models using a computer program called Mimics. The femurs and spine are removed manually to isolate the bone. The model can then be analyzed and the regions defined. The pelvis is split into three pieces using the program Geomagic, the iliac, acetabular, and pubic rami regions. The two cuts are made based around the highest and lowest points of the acetabular cup. From here each cut piece can be mirrored and aligned with the opposing side of the pelvis. Colour deviation maps can then be generated to visualize the asymmetry, as well as the RMS value and the percentage of points within a 2 mm deviation threshold. The average RMS values are below 2 mm and the percentage of points within 2 mm is high. My research reflects that the pelvis is symmetrical and may be used to assist in the surgical planning process of pelvic fractures.

3D Model Optimization of Four-Facet Drill for 3D Drilling Simulation

The article is focused on optimization of four-facet drill for 3D drilling numerical modelling. For optimization, the process of reverse engineering by PowerShape software was used. The design of four-facet drill was created in NumrotoPlus software. The modified 3D model of the drill was used in the numerical analysis of cutting forces. Verification of the accuracy of 3D models for reverse engineering was implemented using the colour deviation maps. The CAD model was in the STEP format. For simulation software, 3D model in the STEP format is ideal. STEP is a solid model. Simulation software automatically splits the 3D model into finite elements. The STEP model was therefore more suitable than the STL model.

ANALYSIS OF WELD JOINT DEFORMATIONS BY OPTICAL 3D SCANNING

This paper presents an analysis of weld joint deformation using optical 3D scanning. The weld joints of bimetals were made by explosion welding (EXW). GOM ATOS II TripleScan SO MV320 equipment with measuring volume 320 × 240 × 240 mm, 5.0 MPix camera resolution and GOM ATOS I 350 with a measuring volume of 250 × 200 × 200 mm, 0.8 MPix camera resolution were used for experimental deformation measurements of weldments. The scanned samples were compared with reference specimens. The angular and transverse deformation were visualized by colour deviation maps. The maximum observed deformations of the weld joints ranged from −1.96 to +1.20 mm.