Numerical uncertainty analysis of active and passive structures in the structural design phase

Abstract

The active approach is nowadays well developed and widely used for various kinds of structures for vibration control or compensation. However, it makes the structure more complex than a passive structure. In this study, active and passive beam structures with the same designed size are compared with regard to uncertainty analysis of the system. The purpose of the comparison is to find a comprehensive way to decide whether an active or a passive approach should be used in the structural design phase. An active beam structure used in this study is a beam structure with one sensor, one actuator, and one controller. The controller is designed to reduce the structural vibration. An active beam structure with a properly designed controller can reduce the structural vibration without changing the structure’s physical dimensions. In contrast, a passive approach can also reduce the structural vibration without additional electric energy for active components, e.g., by changing the material. The comparison of the active and the passive beam structure is based on a beam structure with the same boundary conditions. It is well known that after manufacture and assembly the input parameters of the structure do not exactly correspond to the designed values. Therefore, the input parameters are assumed to be normally or uniformly distributed according to the manufacture tolerance class. They are varied according to the Monte Carlo method to compare the vibration reduction ability of the active and the passive approaches. Finally, uncertainty analysis supports the decision if an active or a passive approach should be used in the structural design phase.