Papers by Keyword: Reverse Engineering (RE)

Abstract: For the problem of complexity of test steps, importance of test data and diversity of error source, introduces the combination of reverse engineering theory and experiment process engineering, analysis the error in data preprocessing process and feedback test scheme, trimming the error by using reverse engineering theory to get more precise test data. According to a member stretching static test in this paper, verification the implementation effect of method based on reverse engineering in test, provide a new idea about trimming method of experiment based on reverse engineering for engineering application.

Abstract: By using a computer vision detection system to obtain high resolution images of a machine part, a kind of reverse design method of solid modeling of irregular planar part with aided implementation of computer vision was proposed in this paper, which integrates image processing function of Matlab software with solid modeling function of computer aided design (CAD) software. The method used a calibrated digital camera to get the image of the tested part, a three-dimensional entity vector model may be built up after image inversion, edge detection, vectorization process of binary image and size matching were operated sequentially. The results of image reverse design showed that it is an easy and convenient way to reverse irregular planar parts based on image processing. One of its remarkable advantages is the saving of design period and the reduction of design cost. Its measurement error can be controlled within 0.1 mm, and can meet general precision requirement of application occasions. Reversed parts may provide a model basis for further analysis on mechanism assembling and motion simulation.

Abstract: In recent years, changes in plant equipment have been becoming more frequent because of the short lifetime of the products, and constructing 3D shape models of existing plants (as-built models) from large-scale laser scanned data is expected to make their rebuilding processes more efficient. However, the laser scanned data of the existing plant has massive points, captures tangled objects and includes a large amount of noises, so that the manual reconstruction of a 3D model is very time-consuming and costs a lot. Piping systems especially, account for the greatest proportion of plant equipment. Therefore, the purpose of this research was to propose an algorithm which can automatically recognize a piping system from terrestrial laser scan data of the plant equipment. Point clouds of a piping system can be extracted based eigenvalue analysis and using region-growing from the laser scanned points. Eigenvalue analysis of the point clouds then allows for recognition of straight portion of pipes. Connecting parts can be recognized from connection relationship between pipes and neighboring points.

Abstract: We propose geometric quality indicators for evaluating the quality of point clouds (sets of scanned points). These indicators represent aspects of quality often considered in practical scanning procedures, such as cloud thickness and cloud density. We defined the indicators mathematically and developed software to compute them, then conducted experiments to evaluate the indicators for point clouds obtained by scanning the same samples with different types of surface scanners and scanning procedures. The results showed that the indicators are capable of highlighting various aspects of point cloud quality.

Abstract: Reverse engineering systems are used to construct mathematical models of physical models such as clay model based on measurement data. In this study, we proposed a reverse engineering method which can construct high quality surface data automatically. This method consists of the following steps; The first globally and regionally smooths measured data based on the target shape by fitting quadric surface to measurement data. The second defines quadric surfaces and converts measurement points into 3D lattice points to obtain uniform measurement data density. As the positions of measurement data are converted from coordinate values into 3D lattice points, it is easier to find neighboring points and clarify neighboring relations between surfaces. The third acquires segment measurement data based on maximum curvatures and normals at each point. The last defines NURBS surfaces for each segment using the least square method to average positional errors. In order to validate the effectiveness of the proposed method, we developed a reverse engineering system and constructed mathematical models through basic experiments using clay car model measurement data.

Abstract: Elementary indentation processes are relatively simple compression processes and they are quite extended in many fields of the industry. Nevertheless, the concatenation of these processes is a new approach and has interest from a technological point of view. In this work the geometry of multiple indentation processes is analyzed on flat surfaces. The state of the formed surface by several types of tools is studied and a model has been developed in order to quantify by means of shape parameters the quality of the theoretical surface depending on the technological and geometrical characteristics of the process.

Abstract: The Reverse Engineering Technology (RET) is extensively employed in the realm of product designing. In this paper, a Three-coordinate Measuring Machine is utilized first to measure the data points of the rearview mirror of a motorcycle, then under UG modeling environment, surface reconstruction is conducted, and lastly procedures like mold splitting and mold core machining are finished upon exercising the Moldwizard Module of UG software. In short, the application of the RET greatly shortened the period of product designing and manufacturing.

Abstract: 3D laser scanning is one of the key technologies of reverse engineering. Digital point cloud is produced by the rapid scanning technology. Some technology about reverse engineering is introduced in this thesis. The curved surface can be generated by the point cloud processing, when the point cloud can be processed by the software called Geomagic Studio.

Abstract: In this paper a step segmentation method for conventional engineering parts which usually comprise by simple analytic surfaces and are important investigation objects of reverse engineering is proposed. In the first segmentation fourteen directions are chosen initially, and a k-mean algorithm according to the normal vectors is used, then the surface is divided to form patches by a region-growing scheme. In order to identify simple analytic surface, curvedness of a patch is set as the criterion by which the surface merged into near constant curvedness region. Especially a novel mean shift algorithm is adopted in this method, that a powerful technique for clustering in image process, and is extended to normal filtering while preserving the features to increase robustness of the method. Experimental evaluations using scan data or noise data demonstrate the efficiency of the proposed method.

Abstract: In this article, based on the research of point cloud acquisition, data preprocessing and surface refactoring of reverse engineering, we analyzed the function and process of the reversing software—IMAGEWARE so as to provide reverse engineering design methods to reversing style design of curved surface refactoring and re-design of products.