Probabilistic analysis of micro-machined fixed-fixed beam for reliability

A realistic approach for modelling a fixed-fixed beam is presented. The use of probabilistic methods to assess the electromechanical behaviour of the beam under the presence of micro-machine manufacturing and process uncertainties is demonstrated. A finite-element model of the beam is constructed using the commercial code ANSYS (10.0). In the standard approach of modelling, existing literature assumes deterministic values for design parameters, however, fabrication of the device introduces some amount of variation in the design parameters. Here, the probabilistic approach is discussed to account for the variability in fabrication. Probabilistic analysis guides the design of the fixed-fixed beam to achieve a robust and reliable design in the most efficient way. The results of the probabilistic design approach on the performance characteristics such as maximum deflection and maximum stress will be discussed.