This paper presents a density-based topology optimization method for designing 3D compliant mechanisms and loadbearing structures with design-dependent pressure loading. Instead of interface-tracking techniques, the Darcy law in conjunction with a drainage term is employed to obtain pressure field as a function of the design vector. To ensure continuous transition of pressure loads as the design evolves, the flow coefficient of a finite element is defined using a smooth Heaviside function. The obtained pressure field is converted into consistent nodal loads using a transformation matrix. The presented approach employs the standard finite element formulation and also, allows consistent and computationally inexpensive calculation of load sensitivities using the adjoint-variable method. For compliant mechanism design, a multi-criteria objective is minimized, whereas minimization of compliance is performed for designing loadbearing structures. Efficacy and robustness of the presented approach is demonstrated by designing various pressure-actuated 3D compliant mechanisms and structures.

中文翻译：

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关于依赖于设计的压力加载 3D 结构和柔顺机构的拓扑优化

本文提出了一种基于密度的拓扑优化方法，用于设计具有设计相关压力载荷的 3D 柔性机构和承重结构。代替界面跟踪技术，达西定律结合排水项被用来获得作为设计矢量函数的压力场。为了确保随着设计的发展压力载荷的连续转变，有限元的流动系数使用平滑的 Heaviside 函数来定义。使用转换矩阵将获得的压力场转换为一致的节点载荷。所提出的方法采用标准有限元公式，并且还允许使用伴随变量方法对负载敏感性进行一致且计算成本低的计算。对于合规机制设计，最小化多标准目标，而最小化合规性则用于设计承重结构。通过设计各种压力驱动的 3D 顺应机制和结构，证明了所提出方法的有效性和稳健性。