Parametric study and optimization of a micro-optical switch with a laterally driven electromagnetic microactuator

Abstract

In this paper we present an in-depth parametric study and structural optimization for a micro-optical switch based on the concept of a laterally driven electromagnetic microactuator (LaDEM). This utilizes the nonlinear behavior of a snap-through buckling occurring in two arch-shaped leaf springs of the switch, when actuated by a distributed Lorentz force induced along the leaf springs. A sudden jump in displacement can facilitate a large actuation stroke suitable for practical applications. The leaf springs are connected to the fixed frame with two meandering parts, which also enhance their flexibility. Thus, an important objective in the design of the. micro-optical switch is to achieve a large displacement with low actuation force. For this purpose, the effect of important geometrical parameters, such as the initial height of the leaf spring and the dimensions of meandering part on the displacement response is first investigated and optimized to satisfy given design specifications. The nonlinear displacement-load response calculated by a modified Riks method in ABAQUS shows good agreement with the measurement result. Nonlinear finite element techniques and optimizations are found to be valuable tools for the analysis and design of microactuators, which utilize a complex nonlinear snap-through buckling behavior.