Research On Composite Scanning And Measurement Methods And Development Of The System In Reverse Engineering

Reverse engineering plays an increasingly important role in creative product design and has accelerated new product development and manufacturing. Acquiring 3D coordinate points efficiently and accurately is the very first step of reverse engineering, and has become a critical issue in reverse engineering. To avoid their respective weaknesses of contact and non-contact measurement methods, the research developed a composite scanning and measurement system, and it will take a promising look in advanced manufacturing industry.In this thesis, based on the study of the present research situation and development at home and abroad of 3D data acquirement. And with the integration of techniques of mechanics, optics, measuring, computer control and software, a composite scanning and measurement system for surfaces is developed, which mainly focuses on data reposition, points distributing and path planning.Main points of the thesis are provided as follow:In Chapter 1, the current study situation of 3D data acquirement for surface was summarized and the problems on contact measurement and non-contact measurement were also pointed out. Then the composite scanning and measurement was put forward.In Chapter 2, data reposition for composite scanning and measurement was discussed. Secondly, three data reposition methods applied in the system were introduced particularly. Finally, applications of three methods were provided.In Chapter 3, strategies and methods for composite scanning and measurement, points distributing, path planning, measurement safety, were presented. Then, measurement path planning based on boundary profile was discussed. At last, strategies for composite mode were brought forward.In Chapter 4, the gross design including hardware structure and software for the composite scanning and measurement system was brought forward, according to the function requirement analysis of the contact measure system.In Chapter 5, some experiments on the system were studied and the factors for its error were analyzed. In the second, a few ways to improve the measure precision were put forward. At last, some representative work pieces were scanned and measured.In Chapter 6, the conclusion was made and the prospect of the future improvement was also given.