Abstract
This paper presents a new method for topology optimization of geometrical nonlinear compliant mechanisms using the element-free Galerkin method (EFGM). The EFGM is employed as an alternative scheme to numerically solve the state equations by fully taking advantage of its capability in dealing with large displacement problems. In the meshless method, the imposition of essential boundary conditions is also addressed. The popularly studied solid isotropic material with the penalization (SIMP) scheme is used to represent the nonlinear dependence between material properties and regularized discrete densities. The output displacement is regarded as the objective function and the adjoint method is applied to finding the sensitivity of the design functions. As a result, the optimization of compliant mechanisms is mathematically established as a nonlinear programming problem, to which the method of moving asymptotes (MMA) belonging to the sequential convex programming can be applied. The availability of the present method is finally demonstrated with several widely investigated numerical examples.
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Project supported in part by the National ‘973’ Key Fundamental Research Projects of China (No. 2003CB716207), the National ‘863’ High-Tech Development Projects of China (No. 2006AA04Z162), and also the Australian Research Council (No. ARC-DP0666683).
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Du, Y., Chen, L. & Luo, Z. Topology synthesis of geometrically nonlinear compliant mechanisms using meshless methods. Acta Mech. Solida Sin. 21, 51–61 (2008). https://doi.org/10.1007/s10338-008-0808-3
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DOI: https://doi.org/10.1007/s10338-008-0808-3