A study of uncertainties in active load carrying systems due to scatter in specifications of piezoelectric actuators

In this paper, uncertainty in an active load-carrying system with an inserted single piezoelectric stack actuator for stabilisation purposes of a slender beam column critical to buckling is investigated. The piezoelectric pre-stressed stack actuator exerts a controlled lateral force on the beam column to stabilize the beam column. The focus of investigation lies on the statistical determination of the influence of scatter of the piezoelectric actuator's assumed blocking force, maximum free stroke, maximum electric driving voltage capabilities and of the stiffness of beam column on the actuator's force-stroke-performance. For that, the actuator's dynamic behavior is described in an analytical model in which force and stroke generated by the actuator depend on the electric driving voltage, on the stiffness of the passive host structure (beam column) at the contact point with the actuator and on the actuator's specifications like e.g. blocking force assumption. Stochastic and estimated uncertainty in the configuration process of the active system due to normally and uniformly distributed scatter in the actuator's blocking force and maximum free stroke capability will be determined by Worst-Case analyses and Monte Carlo simulations. On the basis of these Worst-Case analyses and Monte-Carlo simulations, the effect of uncertain actuator's specifications like blocking force and maximum free stroke on the force-stroke-performance of the piezoelectric actuator is investigated numerically.