Research On The Key Technology Of Scattered Points Processing In Reverse Engineering

Reverse engineering is an advanced designing method that includes digitization of production, reconstruction of CAD model, machining and optimum evaluation of the model. It includes several important steps: data measurement, data processing and model reconstruction. In data measurement, points acquired with optical measuring method are usually scattered points. This paper concentrates on critical techniques of scattered points processing and studied in details based on summarizing and concluding previous works of scholars home and abroad.This paper researches on the existing algorithms of building the topological relationship of scattered points. To the shortcomings of having low efficient and incapable of handling special point clouds, this paper proposes a spacial partition algorithm of finding topological relationship of scattered points, realizes it by using Scoll(a second development language of Imageware)and Visual C++ respectively. Based on the algorithm proposed, this paper also realizes the points filter and coordinates transformation methods. To the redundance of data after the registration, this paper brings forward a new method of data integration based on the idea of grid. For the scan line type point cloud, this paper puts forward a feature extraction method, which extracts characteristic points and obtains closed characteristic frame by using angle-chord principle; After realizing, analyzing and comparing existing algorithm of data reduction, the paper raises and realizes a data reduction method on the basis of mean distance compares the reducing error. Taking account of the deficiency on dealing with great curvature changing point cloud by existing algorithm, this paper sets forth a new data reduction idea based on virtual laser scanning, and then presents the detail flow chart. At last, it submits a kind of data segment method based on field function coping with scattered points.On the whole, this paper brings forward a novel self-adaptive slicing method in coping with the shortcomings of existing reverse engineering software, analyzes the errors created using slicing methods in existing reverse engineering software and proposes the improved algorithm and realizes with the Scoll language.