Papers by Keyword: STL

Abstract: This paper presents the data structure combining from 3D laser scanners direction, for processing rapid prototyping by SLS machine. Formed data will have special structure for combining with the rapid prototyping machine and processing will be more directly and easily. Control algorithm automatically identifies the images from the scanning data.

Abstract: A dental bridge, designed in STL format on a Dental Scanner software, was covered with the porcelain layer in 3-matic Design ©Materialise NV. FEA simulations were made in ANSYS ® Workbench TM ©SAS, Inc. Firstly, was performed the thermal analysis with the Transient Thermal module, and secondly, the structural static analysis with the Static Structural module. The applied masticatory force was of 300 N, and the studied temperatures were 36°C as reference and, as extremes, 0° and 50°C. The purpose was to determine mechanical effects in the bridge structure for a specific design of the dental bridge geometry in order to optimize its design.

Abstract: Based on the in-depth analysis of the structure of DXF, STL files, there is lots of code information in entities of the 3D entity information-stored DXF files, which isn’t good for the use of the valuable information, ASCII format of STL files store the normal vector and vertex coordinates as 3D graphics data for storage in a cramped construction, easy for reading. While binary format of STL files store the information in bytes by rules. Take box as an example, and VC++6.0 programming language is used to program the data information, so as to read and display DXF file information, conduct data transformation according to the set of transformation rules, finally realizing the DXF and STL’s file transformation and displaying content, providing convenience for the file data reading of different platforms.

Abstract: Based on the detailed analysis of the STL file format, VC++ 6.0 programming language was used to extract the STL ASCII and binary file information, at the same time, using the OpenGL triangle drawing technology for graphical representation of the STL file, with rendering functions such as material, coordinate transformation, lighting, et al, finally realizing the loading and three-dimensional display of STL ASCII and binary file formats.

Abstract: This paper provides the details of continuous cutting technology to architectural model made by EPS. To solve the interference problem between outline surface and hot cutting-wire in the cutting process, STL model projection profile method is used. Slicing algorithm based on grouping matrix is proposed to cutting the outline model continuously. Local topological relations in each group are established to improve the efficiency of slicing cutting. In order to apply this algorithm to the actual process better, automatic programming system with Visual C + + 6.0 based on STL model is developed, which used the 5-DOF CNC thermal device to cut the model. The experiment shows that this technology can cut the outline architectural model efficiently and accurately.

Abstract: Data fitting approach based on test data is commonly adopted on analyzing of thermal effect due to the thruster plume impingement on communication satellites, however, the existing methods are only available for the appendages which are regularly shaped or could be formulated. In this paper, a plume impingement analyzing approach for irregularly shaped appendages is present. The STL (Stereo Lithographic) data is firstly derived from the three-dimensional model of the appendages. Then the STL data are made a kind of interpolation to get small particle size in order to obtain a precise analyzing result. Finally, the normal vector and the location of each triangle grid are obtained from the STL data to form a new model for plume impingement analyzing on irregularly shaped appendages. The new method is proved correct by comparing with PLUME software and the method given in [4].The application range of analyzing exhaust plume impingement on communication satellites can be widely extended by the proposed method.

Abstract: A new methodology of generating optimized tool paths for incremental sheet forming is proposed in this work. The objective is to make parts with improved accuracy. To enable this, a systematic technique of creating features using a morph mapping strategy is developed. This strategy is based on starting with a shape different from the final shape, available as a triangulated STL model, and using step-wise incremental deformation to the original mesh to arrive at the final part shape. Further, optimal tool path generation requires intelligent sequencing of partial tool paths that may be applied specifically to certain features on the part. The sequencing procedure is discussed next and a case study showing the application of the integrated technique is illustrated.

Abstract: Computational simulation relies on valid and accurate representations of the geometry of objects being simulated. However, the Stereo Lithography (STL), one of the most commonly used formats for computational simulation, may be invalid with several kinds of defects when the geometry is too geometrically and topologically complex. In many cases, castings have the most complicated geometries in the world, and its geometries in STL format always contain some defects. The implicit surface is a much more robust geometry representation than STL. With the representation in the implicit surface, most of the defects in STL can be cleared and ignored. This paper presents a method to fast construct the implicit surface for arbitrary complex casting geometries in the format of STL.

Abstract: Aiming at solving the problem of the complicated structure and difficult 3D modeling of cross wedge rollors, the article does some research on the 3D cross wedge die based on STL documents. In accordiance with the data of parametric cross wedge die, adopting the STL document format, aotomatically construct the 3D shape of the model, this method can increase the efficiency of designing the modeling of cross wedge rollors; since most CAM, CAE systems can read STL document, this method can speed up the CAE and CAM systems in order to provide 3D geomatrical model quickly.

Abstract: Triangulating the point cloud get STL model, a planar spiral line can obtain by offset the STL mode. Along the Z axis projecting towards the Equidistant surface of STL model will get a spatial spiral line, it can be used in numerical control high speed machining.