This paper presents a multiscale design method for simultaneous topology optimization of both macrostructures and microstructures.Geometric features are extended as design primitives at both macro and micro scales and...This paper presents a multiscale design method for simultaneous topology optimization of both macrostructures and microstructures.Geometric features are extended as design primitives at both macro and micro scales and represented by Level Set Functions(LSFs).Parameters related to the locations,sizes,and orientations of macro and micro features are considered as design variables and optimized simultaneously.In the overlapping areas of different macro features,embedded microstructures are optimally figured out as the solution of the corresponding sub-optimization,problem.In this study,the eXtended Finite Element Method(XFEM)is implemented for structural and sensitivity analyses with respect to design variables.This method has the advantage of using a fixed grid independent of the topology optimization process.The homogenization procedure is applied to calculate the effective properties of considered microstructures in each macro feature.Numerical examples are presented to illustrate the effectiveness of the proposed method.Results depict that the multiscale design cannot obviously improve structural stiffness compared with a solid-material design under the linear elastic condition.展开更多
Component sequence preservation is an intrinsic requirement in typical engineering applications, such as deployable chain-likestructures, 3D printing structures with contour-parallel toolpaths, additive manufacturing ...Component sequence preservation is an intrinsic requirement in typical engineering applications, such as deployable chain-likestructures, 3D printing structures with contour-parallel toolpaths, additive manufacturing of continuous fibre-reinforcedpolymer structures, customized stents, and soft robotics parts. This study presents a feature-driven method that preservescomponent sequences accounting for engineering requirements. The chain-of-bars design variables setting scheme is developedto realize the sequential component’s layout, which sets the current bar’s end point as the next bar’s start point. The total lengthof the printing path is constrained to reduce the consumption of material accurately. Also, the angle between adjacent bars isconstrained to avoid sharp angles at the turning point of the 3D printing path. Next, the sensitivity analysis considering theinter-dependence of substructures is performed. Several numerical examples are given to demonstrate the validity and merits ofthe proposed method in designing structures preserving component sequences.展开更多
This work elaborates an innovative mesh denoising approach that combines feature recovery and denoising in an alternating manner.It proposes a feature-driven variational model and introduces an iterative scheme that a...This work elaborates an innovative mesh denoising approach that combines feature recovery and denoising in an alternating manner.It proposes a feature-driven variational model and introduces an iterative scheme that alternates between feature recovery and the denoising process.The main idea is to estimate feature candidates,filter noisy face normals in the smooth(non-feature)domain,and utilize erosion and dilation operators on the feature candidates.By imposing connectivity constraints on normal vectors with large amplitude variations,the proposed scheme effectively removes noise and progressively recovers both sharp and small-scale features during the iterative process.To validate its effectiveness,this work conducts extensive numerical experiments on both simulated and real-scanned data.The results demonstrate significant improvements in noise reduction and feature preservation compared to existing methods.展开更多
基金supported by National Key Research and Development Program of China(No.2017YFB1102800)National Natural Science Foundation of China(Nos.11432011,11620101002,11722219).
文摘This paper presents a multiscale design method for simultaneous topology optimization of both macrostructures and microstructures.Geometric features are extended as design primitives at both macro and micro scales and represented by Level Set Functions(LSFs).Parameters related to the locations,sizes,and orientations of macro and micro features are considered as design variables and optimized simultaneously.In the overlapping areas of different macro features,embedded microstructures are optimally figured out as the solution of the corresponding sub-optimization,problem.In this study,the eXtended Finite Element Method(XFEM)is implemented for structural and sensitivity analyses with respect to design variables.This method has the advantage of using a fixed grid independent of the topology optimization process.The homogenization procedure is applied to calculate the effective properties of considered microstructures in each macro feature.Numerical examples are presented to illustrate the effectiveness of the proposed method.Results depict that the multiscale design cannot obviously improve structural stiffness compared with a solid-material design under the linear elastic condition.
基金supported by the Chinese Studentship Council(Grant No.201908060224)the Young Talent Fund of Association for Science and Technology in Shaanxi,China(Grant No.20230240)+1 种基金the National Natural Science Foundation of China(Grant No.11972308)Queen Mary University of London with the PhD fee waiver.
文摘Component sequence preservation is an intrinsic requirement in typical engineering applications, such as deployable chain-likestructures, 3D printing structures with contour-parallel toolpaths, additive manufacturing of continuous fibre-reinforcedpolymer structures, customized stents, and soft robotics parts. This study presents a feature-driven method that preservescomponent sequences accounting for engineering requirements. The chain-of-bars design variables setting scheme is developedto realize the sequential component’s layout, which sets the current bar’s end point as the next bar’s start point. The total lengthof the printing path is constrained to reduce the consumption of material accurately. Also, the angle between adjacent bars isconstrained to avoid sharp angles at the turning point of the 3D printing path. Next, the sensitivity analysis considering theinter-dependence of substructures is performed. Several numerical examples are given to demonstrate the validity and merits ofthe proposed method in designing structures preserving component sequences.
基金supported in part by the National Natural Science Foundation of China(62476219,62206220,12271140,12326609)the Young Talent Fund of Association for Science and Technology in Shaanxi,China(20230140)+1 种基金the Chunhui Program of Ministry of Education of China(HZKY20220537)the Fundamental Funds for the Central Universities(G2023KY0601).
文摘This work elaborates an innovative mesh denoising approach that combines feature recovery and denoising in an alternating manner.It proposes a feature-driven variational model and introduces an iterative scheme that alternates between feature recovery and the denoising process.The main idea is to estimate feature candidates,filter noisy face normals in the smooth(non-feature)domain,and utilize erosion and dilation operators on the feature candidates.By imposing connectivity constraints on normal vectors with large amplitude variations,the proposed scheme effectively removes noise and progressively recovers both sharp and small-scale features during the iterative process.To validate its effectiveness,this work conducts extensive numerical experiments on both simulated and real-scanned data.The results demonstrate significant improvements in noise reduction and feature preservation compared to existing methods.
