Abstract:A bounded Hrovat semi-active control strategy providing the adequate performance control of general stochastic dynamical systems is proposed in the present paper. It hinges on the generalized density evolution equation recently developed to reveal the intrinsic relationship between the physical mechanism and probability density evolution of systems. An earthquake-excited system controlled by a Magnetorheological (MR) damper is investigated for illustrative purpose, of which two parameters are laid down, i.e. damping coefficient and maximum Coulomb force, according to the criterion of system second-order statistics evaluation and perfectly tracing the optimal active control forces. Numerical results reveal that the appropriately designed semi-active controller can achieve almost the same effect of the active controller in the probabilistic sense. The example further proves that the advocated semi-active control strategy could prompt the dynamic damping performance of the MR damper, behaving as a type-like Bouc-Wen model with the strength deterioration, the stiffness degradation and the pinch effect.
