Ferruh Yildiz

The registration of point cloud data from range imaging camera

AbstractThe measurement and 3D modelling techniques have been evolved as parallel technological improvements. Every new technique provides an opportunity for low-cost and fast measurements. The latest method for 3D measurement is the range imaging (RIM) camera. The new period in photogrammetry and 3D modelling applications has begun with the RIM cameras, and it has brought new research areas for scientists. The measurement capabilities, accuracies and application areas of RIM cameras have been increased by the time. In this study, the registration of point cloud data of RIM camera was investigated to perform 3D modelling task.

Laser Scanning and Data Integration for Three-Dimensional Digital Recording of Complex Historical Structures: The Case of Mevlana Museum

Terrestrial laser scanning method is widely used in three-dimensional (3-D) modeling projects. Nevertheless it usually requires measurement data from other sources for full measurement of the shapes. In this study a 3-D model of the historical Mevlana Museum (Mevlana Mausoleum) in Konya, Turkey was created using state-of-the art measurement techniques. The building was measured by terrestrial laser scanner (TLS). In addition, some shapes of the indoor area were measured by a time-of-flight camera. Thus, a 3-D model of the building was created by combining datasets of all measurements. The point cloud model was created with 2.3 cm and 2.4 cm accuracy for outdoor and indoor measurements, and then it was registered to a georeferenced system. In addition a 3-D virtual model was created by mapping the texture on a mesh derived from the point cloud.

Range and image sensor combination for three‐dimensional reconstruction of objects or scenes

Purpose – Laser scanning is increasingly used in many three‐dimensional (3‐D) measurement and modeling applications. It is the latest technique used in 3‐D measurement, and is becoming increasingly important within a number of applications. However, many applications require photogrammetric data in addition to laser scanning data. The purpose of this paper is to present a range and image sensor combination for three‐dimensional reconstruction of objects or scenes.Design/methodology/approach – In this study, a Nikon D80 camera was mounted on an Ilris 3D laser scanner and CPP was estimated according to the laser scanner coordinate system. The estimated CPP was controlled using three different methods which were developed in this study and a sample application as coloring of point cloud using image taken by the camera mounted on the laser scanner was performed.Findings – It was found that when a high‐resolution camera is mounted on laser scanners, camera position parameters (CPP) should be estimated very acc...

The use of stereophotogrammetry in oral surgery: Measurement of area changes after secondary epithelization and grafting vestibuloplasties

OBJECTIVE Stereophotogrammetry (SPT) is a method in which three-dimensional coordinates are calculated from multiple two-dimensional projections. The purpose of this study was to compare the surface area changes between the secondary healing and grafting vestibuloplasty techniques in the mandible by using a stereophotogrammetric technique (SPT). PATIENTS AND METHODS Thirteen patients were included in this study: six patients were managed by using full-thickness skin or palatal mucosa grafts (two full-thickness palatal mucosal grafts and four full-thickness skin grafts); the remaining seven patients, who did not accept a second surgery for graft harvesting, underwent secondary epithelization vestibuloplasties. Postoperative changes of surgical areas were measured by using SPT. STATISTICAL ANALYSES The Wilcoxon (intragroup comparisons) and Mann-Whitney U (intergroup comparisons) tests were used for analysis of data. RESULTS In the grafting vestibuloplasty group, the surface area gain was statistically significant (P < 0.05). In the secondary epithelization vestibuloplasty group, there was no significant difference (P > 0.05), with even decrease of surface area being noted in some cases. CONCLUSION SPT is a valid method for measurement of intraoral soft tissue changes.