Experimental Research On3D Scan Methods Of Complex Parts For Rapid Prototyping

As the market competition grows intensively, companies can win in the competition if they have the abilities to develop new products in a short time. The products are becoming more and more complicated, especially with the wildly use of cars, planes, appliances, toys, human organs which are characterized with free-form surfaces. Reverse engineering and rapid prototyping are powerful technologies to develop this kind of products because the development period would be shortened and the product quality would be improved. This paper study the3D scanning, point cloud processing, RE modeling and RP processing of these parts with free-form surfaces, including these details as follow:(1) This paper compared several popular scanners and then finds out their advantages and disadvantages. Though the study of reverse engineering software Imageware and Geomagic studio, comparing the different parts of each one and finding their differences of reconstruction from point cold, Point cloud processing was studied in this paper, especially issues such as point alignment, point character, noise reduction, point sampling and point cloud segmentation, that is meaningful for the model reconstruction.(2) STL format is the acquiescent date transmission format, and it is always a necessary step for the RE model. Several triangulation algorithms are compared and the optimization principles of triangulation are studied. Some basic issues about triangulation and curves and surfaces fitting are studied, then some instructive conclusions are come.(3) Model reconstruction is the key step in the whole process of reverse engineering, this paper study the basic theory of fitting of curves and surfaces, and the fitting tolerance evaluation, tolerance controlling, smoothness evaluation and so on. This paper study the methods of RE reconstruction of models with free-form surfaces, and figure out different ways for different models. A mandible which is built by RP processing from medical CT date is scanned, so the error of integrated system based REV-scan handheld laser scanner,3DSS-STD-II scanner and Eden2503D printer can be evaluated. Though the scanning and RE reconstruction of a car door mold, methods in this paper are proved to be feasible. (4) The technical process of Eden250is studied, and the mandible scanned in the preamble is simulated on this RP system. The integration method of reverse engineering and rapid prototyping is discussed. The reason why there is an error of the integrated system is studied, and the solution to improve the accuracy is given in the paper.