Papers by Keyword: Surface Reconstruction

Abstract: With the demand of acquiring the high-accuracy blade surface by repeated grinding, a theoretical investigation is presented on the rapid measurement for the grinding process. The polygon approximation method is used in this paper which uses the corner points as the starting points compared with the traditional polygon approximation. The feature points are obtained iteratively from the starting points, which have the maximum curvatures in the corresponding region. In order to obtain the blade surface, this paper uses the chosen feature points as control points to construct the initial fitting B-spline surface and then modifies them to meet the the convergence conditions. According to the experimental results, the B-spline fitting surface errors have little difference from the errors obtained by the feature points. The fitting results are potentially useful for the calculating of machining allowance and decreasing the measurement time in the machining process.

Abstract: In order to solve the problem of poor steam turbine blade processing efficiency, and on the basis of analyzing the turbine blade surface and the existing processing methods, a model of circular cutter turbine blade machining is built. By comparing the tool paths of horizontal and vertical section envelope machining, choosing quasi-vertical cross section envelope machining method and utilizing the original datum and NURBS surface matching mathematic methods, this paper provides an algorithm of residual height calculating, and based on this, the tool path can be planned. Datum show that, the tool path of circular cutter machining blades is much longer than the tool path of ball-end cutter envelop milling machining blades, and the machining efficiency is also highly enhanced.

Abstract: Studied the modeling strategy and application features of rapid surfacing reconstruction system. The 3D digital model reconstruction of real mobile phone as an example, using non-contact optical 3D scanning point cloud data access to mobile phone, get the mobile phone CAD model through data processing by point stage, polygon stage and shape stage, and the various stages of the process and the target are discussed in this paper.

Abstract: Surface reconstruction is a hot topic in the field of computer graphics. Power Crust algorithm can reconstruct a triangle mesh that is topologically valid and convergent to the original surface. But it can not handle the points with noised and its running time is long. In this paper an efficient surface reconstruction algorithm for noisy samples is proposed. Firstly, we delete the noise by bilateral filter. Secondly, a non-uniformly sampling method is used to resample the input data in order decrease the number of the samples to the local feature size before reconstruction. Finally, Power crust algorithm is be used to reconstructed the surface. From the experiments, it can be seen the speed of reconstruction is increased and the features of the surface are preserved.

Abstract: This study proposes a novel suface reconstruction method. Surface reconstruction based on Support Vector Machine (SVM) is a hot topic in the field of 3D surface construction. But it is difficult to apply this method to noisy cloud points and its running time is very long. In this paper, firstly, Fuzzy c-means (FCM) is used to delete the large-scale noise, and then a feature-preserved non-uniform simplification method for cloud points is presented, which simplifies the data set to remove the redundancy while keeping down the features of the model. Finally, the surface is reconstructed from the simplified data using SVM. Both theoretical analysis and experimental results show that after the simplification, the performance of method for surface reconstruction based on SVM is improved greatly as well as the details of the surface are preserved well.

Abstract: When remanufacturing complex surface parts, such as twisted turbine blade, it is difficult to obtain an accurate model. A segmentation and iterative surface reconstruction algorithm for repair of twisted turbine blade is described. The algorithm reconstructs the blade surface by segmenting the data points base on design intent and iterating the control points. The continuity of the fitted closed surface is tested by UG and the error of the fitted surface can be verified with Imageware by comparison with three different blades. It shows that the time complexity of the algorithm is reduced greatly, and the error is within the acceptable limits.

Abstract: This paper presented a method for measuring the residual space between clothing and human body based on 3D scanning devices. In data collecting procedure, the 3D scanning devices were used to collect original point cloud of apparels and human body. The Geomagic software was used to process the noise reduction and surface reconstruction. In measuring procedure, the volume was calculated by algorithm. Therefore, we can get the value of the residual space between clothing and human body.These residual space is called air gap. Thickness of the air gap is closely related to thermal insulation properties [1] and thermal wet comfort performance of clothing. Meanwhile, the stress levels of apparels on human body can be determined through observation [2], so this technology can be used in the field of fashion design. In addition, 3D virtual try-on system is one of the applications with important value [3].

Abstract: The precision analysis of surface model is one of the key technologies in reverse engineering.Analyzed the error sources of surface accuracy in reverse engineering,proposed an evaluation indicators of the surface accuracy,which are whether the reconstructed model is qualified.Taking rearview mirror for example,compared with the reconstructed model and the original point cloud data by three-dimensional and two-dimensional methods in Geomagic Quality software,obtained the deviation value of the whole model and three different directions,the results show that the error of the most data points is in the range of permissible,which is less than the pre-set error;take the reconstructed surface data and the original point cloud data for comparison, more than 94% of the total data points is in the range of permissible, prove that the fitting surface accuracy is qualified.

Abstract: In order to improve the accuracy of prospecting and efficiency of coal extraction, it is necessary to understand the geological construction deeply. Therefore, the reconstruction of fault surface models is highly important. Reconstructe surface from an unorganized cloud of points by using the RBF neural networkcs advantages of approximating no-linear function, and the algorithmcs scheme and analyses were given and the proposed method was applied to the coal surface reconstruction, this neural network can not only approximate the surface with high precision but also has good smoothness.

Abstract: Atomic force microscopy (AFM) is the useful tool for measuring the micro fabricated devices. Measuring sample surface with AFM, tip-induced distortions are serious problem for accurate measurement. In order to overcome this problem, many studies are reported to reconstruct surface image to original sample surface. We studied method of reconstruction technique of the AFM image by using estimated 3-D tip shape from the impulse response technique. To reconstruct the image of the sample surface, we used a morphological reconstruction process. We demonstrated how to obtain the 3-D tip from the using impulse response technique and then how to reconstruct the 3-D AFM image using estimated tip shape.