In Additive Manufacturing field, the current researches of data processing mainly focus on a slicing process of large STL files or complicated CAD models. To improve the efficiency and reduce the slicing time, a paral...In Additive Manufacturing field, the current researches of data processing mainly focus on a slicing process of large STL files or complicated CAD models. To improve the efficiency and reduce the slicing time, a parallel algorithm has great advantages. However, traditional algorithms can＇t make full use of multi-core CPU hardware resources. In the paper, a fast parallel algorithm is presented to speed up data processing. A pipeline mode is adopted to design the parallel algorithm. And the complexity of the pipeline algorithm is analyzed theoretically. To evaluate the performance of the new algorithm, effects of threads number and layers number are investigated by a serial of experiments. The experimental results show that the threads number and layers number are two remarkable factors to the speedup ratio. The tendency of speedup versus threads number reveals a positive relationship which greatly agrees with the Amdahl＇s law, and the tendency of speedup versus layers number also keeps a positive relationship agreeing with Gustafson＇s law. The new algorithm uses topological information to compute contours with a parallel method of speedup. Another parallel algorithm based on data parallel is used in experiments to show that pipeline parallel mode is more efficient. A case study at last shows a suspending performance of the new parallel algorithm. Compared with the serial slicing algorithm, the new pipeline parallel algorithm can make full use of the multi-core CPU hardware, accelerate the slicing process, and compared with the data parallel slicing algorithm, the new slicing algorithm in this paper adopts a pipeline parallel model, and a much higher speedup ratio and efficiency is achieved.展开更多
Selective laser melting （SLM） is one of the most popular additive manufacturing （AM） technologies for metal parts. Slicing result, especially for the different dimensional slicing geometry and its topology, plays ...Selective laser melting （SLM） is one of the most popular additive manufacturing （AM） technologies for metal parts. Slicing result, especially for the different dimensional slicing geometry and its topology, plays an important role because of the thermodynamic behavior of metal powders. To get correct geometry and reliable topology, a slicing strategy for SLM is proposed. The unavoidable numerical error caused by sampling and geometric transformation is suppressed firstly, according to shifting the z-coordinate of a vertex with a small value such the shifted vertex is on a slicing plane. The result of vertex-shifting makes it possible to identify different geometric features such as skin surfaces, overhang surfaces, extreme edges and volumetric solid. Second, from geometric primitives a hierarchy of axis-aligned bounding boxes （AABBs） is constructed and used to speed up intersection of slicing planes against sets of triangles. All intersecting segments are given different signs to depict their geometric or topological information. Based the different signs, the different dimensional geometry that is eventually represented by simple and anticlockwise oriented polygons, are identified. Finally, the polygons are classified and nested in a multi-tree data structure set to produce correct topological relations. The result of digital and physical experiments shows the proposed slicing strategy is feasible and robust.展开更多
In the last decade,3D printing,especially fused deposition modeling(FDM),has revolutionized manufacturing with intricate designs.Traditional 3-axis FDM printers face challenges with complex geometries,but 5-axis versi...In the last decade,3D printing,especially fused deposition modeling(FDM),has revolutionized manufacturing with intricate designs.Traditional 3-axis FDM printers face challenges with complex geometries,but 5-axis versions offer more design freedom.However,it requires specialized strategies.This research presents a model for 5-axis FDM printers using Bézier curves with an algorithm to enhance print quality.The result shows significant accuracy improvements,especially for curve-based tasks.In addition,this study deepens the understanding of 5-axis FDM technology,setting a solid basis for further research and potentially refining manufacturing methods.展开更多
文摘In Additive Manufacturing field, the current researches of data processing mainly focus on a slicing process of large STL files or complicated CAD models. To improve the efficiency and reduce the slicing time, a parallel algorithm has great advantages. However, traditional algorithms can＇t make full use of multi-core CPU hardware resources. In the paper, a fast parallel algorithm is presented to speed up data processing. A pipeline mode is adopted to design the parallel algorithm. And the complexity of the pipeline algorithm is analyzed theoretically. To evaluate the performance of the new algorithm, effects of threads number and layers number are investigated by a serial of experiments. The experimental results show that the threads number and layers number are two remarkable factors to the speedup ratio. The tendency of speedup versus threads number reveals a positive relationship which greatly agrees with the Amdahl＇s law, and the tendency of speedup versus layers number also keeps a positive relationship agreeing with Gustafson＇s law. The new algorithm uses topological information to compute contours with a parallel method of speedup. Another parallel algorithm based on data parallel is used in experiments to show that pipeline parallel mode is more efficient. A case study at last shows a suspending performance of the new parallel algorithm. Compared with the serial slicing algorithm, the new pipeline parallel algorithm can make full use of the multi-core CPU hardware, accelerate the slicing process, and compared with the data parallel slicing algorithm, the new slicing algorithm in this paper adopts a pipeline parallel model, and a much higher speedup ratio and efficiency is achieved.
基金Supported by Key Programs of the Chinese Academy of Sciences(No.KGZD-EW-T0)Research Fund for Scientific and Technological Projects of Chongqing(No.2012gg B40003 and cstc2013yykf C00006)
文摘Selective laser melting （SLM） is one of the most popular additive manufacturing （AM） technologies for metal parts. Slicing result, especially for the different dimensional slicing geometry and its topology, plays an important role because of the thermodynamic behavior of metal powders. To get correct geometry and reliable topology, a slicing strategy for SLM is proposed. The unavoidable numerical error caused by sampling and geometric transformation is suppressed firstly, according to shifting the z-coordinate of a vertex with a small value such the shifted vertex is on a slicing plane. The result of vertex-shifting makes it possible to identify different geometric features such as skin surfaces, overhang surfaces, extreme edges and volumetric solid. Second, from geometric primitives a hierarchy of axis-aligned bounding boxes （AABBs） is constructed and used to speed up intersection of slicing planes against sets of triangles. All intersecting segments are given different signs to depict their geometric or topological information. Based the different signs, the different dimensional geometry that is eventually represented by simple and anticlockwise oriented polygons, are identified. Finally, the polygons are classified and nested in a multi-tree data structure set to produce correct topological relations. The result of digital and physical experiments shows the proposed slicing strategy is feasible and robust.
基金supported by the Na-tional Natural Science Foundation of China(Nos.51575266,52075258)。
文摘In the last decade,3D printing,especially fused deposition modeling(FDM),has revolutionized manufacturing with intricate designs.Traditional 3-axis FDM printers face challenges with complex geometries,but 5-axis versions offer more design freedom.However,it requires specialized strategies.This research presents a model for 5-axis FDM printers using Bézier curves with an algorithm to enhance print quality.The result shows significant accuracy improvements,especially for curve-based tasks.In addition,this study deepens the understanding of 5-axis FDM technology,setting a solid basis for further research and potentially refining manufacturing methods.
