REVERSE GEOMETRIC MODELLING AS A PART OF REVERSE ENGINEERING - ACCURACY OF FITTING CYLINDER

This research investigates reverse geometric modelling in CAD software PowerShape for reconstructing polygonal 3D models. The process utilises specialised functions for reverse modelling to create 3D CAD models. Integral to this is integrating 3D digitisation data, with a sample part digitised using the METROTOM 1500 industrial computer tomograph. The study applies the fitting method to a polygonal cylindrical mesh, employing techniques like point reduction, smoothing, and fitting surface diameter based on points cloud. Notably, the number of points on the cylinder's mesh directly impacts the resulting diameter. Reducing points increases the diameter; for instance, 26,934 points cloud a 29.898 mm diameter, while a 90% reduction to 2,385 points results in a 30.001 mm diameter. The research highlights the effect of polygon mesh smoothing, with values of 0.2 and 0.5 significantly reducing the reconstructed cylindrical surface's diameter. However, further smoothing does not alter the diameter.