Μορφοποίηση πιστών αντιγράφων αρχαίων αντικειμένων με εφαρμογή μεθόδων αντίστροφης μηχανολογίας και ταχείας πρωτοτυποποίησης ; Modeling and reconstruction of ancient objects by means of Reverse Engineering and Rapid Prototyping

In this doctoral dissertation discussed various sections of Reverse Engineering and Rapid Prototyping aiming to develop and apply algorithms and methodologies for modeling objects and methods for producing precise copies of objects with complicated geometry. The methodologies are applied mainly to archaeological findings. Initially in this paper algorithms were developed and applied for solving major problems in modeling objects using reverse engineering processes. These problems are the automatic registration of two or more point clouds and the objects modeling from a small number of points. According to the registration of point clouds problem a hybrid method was developed to determine optimum solutions. The hybrid algorithm combines a genetic algorithm (GA) with a hill climbing method (quasi-Newton algorithm - QNA) and a constraints handling method (CHM). The proposed algorithm is very efficient in finding the optimal solution in a reduced computational time. According to the second problem a Reverse Engineering method for modeling parts using a 3D measuring device (CMM) or other 3D scanner by means of polynomial curves (splines) is developed. Initially point’s coordinates of an object are measured, by means of a Coordinate Measuring Machine (CMM). The simulation of surfaces via the software of Reverse Engineering, in an automatic way, has as result the generation of many elementary surfaces of free form as well as phenomena of discontinuity among them. In order to exceed these imperfections, the developed algorithm simulates surfaces with 3rd degree curves. As data for the program are received the points coordinates of initial curves that result from the measurements and the allowed divergence of proposed 3rd degree curves. The algorithm selects the less possible points and links them with proposed 3rd degree curves, in order to satisfy the allowed deviation. The proposed algorithm uses a smaller amount of points to produce the polynomial curves of 3rd degree that approach with high accuracy the measured ...