Li Xinqing Wang Zhenpei, Mi Yongzhen, David W. Rosen, Wang Yingjun, Isogeometric Topology Optimization for Nonlinearities in 4D Printing Design, International Conference on Future of Additive Manufacturing, Aug. 2025, Singapore
Abstract:
Topology optimization has been a crucial tool for improving the performance and efficiency of 3D additive manufacturing (AM) products. However, current topology optimization methods developed for 3D AM are insufficient when applied to four-dimensional additive manufacturing (4DAM) processes. This inadequacy arises from the complex nature of 4DAM, which involves nonlinear deformations, nonlinear material behaviors, and nonlinear loading conditions — factors that are not adequately addressed by existing 3D AM optimization frameworks.
Isogeometric analysis (IGA) offers significant advantages for such challenges, including better convergence for nonlinear problems, cost-effective simulations compared to traditional finite element methods (FEM), and straightforward multi-level discretization for integrated design and analysis. Building upon these strengths, this study proposes a multi-resolution isogeometric topology optimization framework to tackle the nonlinearities inherent in 4DAM design, aiming to balance high computational cost and convergence issues effectively.
The proposed framework employs a NURBS-based material density field in the design space, based on the same NURBS representation with varying resolutions for nonlinear simulations in the analysis space. A refined resolution in the design space ensures sufficient geometric detail, while a coarser resolution in the analysis space enables efficient nonlinear analysis to accelerate the optimization process. However, significant disparities between design and analysis resolutions can lead to unrealistic solutions due to incompatible interpolations of material density. To address this issue, an adaptive analysis resolution strategy is introduced to improve design quality across different optimization stages.
Numerical examples, including sensitivity analysis via the adjoint method, are presented for both structural compliance minimization and compliant mechanism design, demonstrating the effectiveness of the proposed framework. Furthermore, soft robotic designs with embedded actuators, potentially fabricable through 4DAM, are explored. To facilitate fabrication, a post-processing tool for generating smooth and editable models will also be developed.
License type:
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Funding Info:
This research / project is supported by the Agency for Science, Technology and Research - Career Development Fund
Grant Reference no. : C210112026
This research / project is supported by the Agency for Science, Technology and Research - Start-up fund
Grant Reference no. :