Computational optimization of adhesive microstructures based on a nonlinear beam formulation
Tóm tắt
This paper presents computational shape optimization of adhesive microstructures. Adhesion is described by van der Waals interactions. These are incorporated into a nonlinear, geometrically exact beam formulation. The cross section of the beam is considered to vary along the beam length. The resulting shape variations are then used for optimization, by maximizing the contact surface of the beam, maximizing the external work during peeling, and minimizing the strain energy. A nonlinear finite element formulation is used to discretize and solve the resulting system. Optimization is then based on a genetic algorithm. Apart from the actual optimization procedure, this work also focuses on the problem formulation and the corresponding choice of problem parameters. In order to explore the properties of the design space, a large number of benchmark cases is examined. The optimization parameters of the model are investigated and several design guidelines are drawn. It is shown that, depending on the chosen model parameters, the computed optimal beam shape resembles the shape of gecko spatulae.
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