Optimization of the bistable mechanism properties based on radial basis function agent model

This paper describes an optimization method for analyzing the mechanical characteristics of a bistable structure used in inertial switch. For the purpose of obtaining the optimal design of the bistable structure, a robust optimization based on radial basis function agent model is developed, to minimizing variability of the performance due to fabrication errors and changes of material properties. The two-objective optimization function that minimizes the uncertainty of the forward threshold force and the reverse threshold force in the bistable characteristic curve is determined. As a result of the robust optimization, the maximum force used to toggle the bistable beam is reduced from
$21.81\ \mu \mathrm{N}$
to
$13.81\ \mu \mathrm{N}$
and the contact force band at 95% confidence is narrowed from
$\pm 1.68\ \mu \mathrm{N}$
to
$\pm 0.82\ \mu \mathrm{N}$
, verified by a finite element simulation in ANSYS.