Research On Twin-Screw Modeling Based On Surface Reconstruction Via Reverse Engineering

This paper proposes a new method for modeling Twin-Screw surface via reverse engineering. Mathematic model of Twin-Screw elements is reconstructed using Computer Aided Geometric Design(CAGD). And dynamic simulation of Twin-Screw is presented.First, Twin-Screw element is scanned via 3D laser scanner. Initial 3D point clouds are obtained by setting the one-off scanning route according to the shape of the targets. Four de-noise methods, including field de-noising, line de-noising, angle de-noising and point de-noising, are applied to the initial data points. With B-spline, the loop data points are generated by fitting the data points which are pre-processed by using point clouds slicing method.Second, this paper presents a new surface reconstruction method based on piecewise surface reconstruction. By parameterizing the data points using bi-directional normalized progressive length of chords, piecewise product Bezier surface is constructed. The parametric surface of Twin-Screw element is rendered according to the mathematical model of Twin-Screw surfaces.Finally, in order to testify this reconstruction method, this paper present the algorithms of solving the parametric value of projection of point onto curve and surface. Error analysis shows that this reconstruction method is feasible to Twin-Screw modeling.