In this article, the static behavior of micromirrors under the effect of capillary force is studied. The dimensionless equations governing the static behavior and the pull-in state of the micromirror under capillary force are obtained, and the effects of different geometrical parameters on the pull-in angle of micromirrors are investigated. The static behavior of micromirrors is studied both numerically and analytically using the homotopy perturbation method. It is observed that with increasing the instability number defined in this article, the rotation angle of the micromirror is increased and suddenly the pull-in occurs. The results of the presented model are then verified by comparing them with the results of finite element simulations performed in the commercial finite element model software ANSYS. The agreement between the results of finite element model and those of the proposed analytical model shows that homotopy perturbation method can be used as a fast and accurate tool for predicting mirror’s behavior under capillary force.
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