Abstract
This paper proposes a new design method of semi-active optimal control system. This method uses the nonlinear predictive control theory to design a controller and considers nonlinear characteristic of damper that possess variable parameters. This controller predicts the nonlinear response of continuous system one-step ahead by using the state equation. Control inputs are determined by minimization of predictive tracking errors and control inputs. Moreover, this paper proposes a novel MR damper with an expanded variable damping region using both electric and parmanent magnets. Damping coeffecient of the damper is made increased by adding positive current and decreased by negative current. Proposed approach is applied to vibration control of multi buildings connected with the MR damper. Effectiveness of the presented controller and MR damper is examined through simulation and experiment under random and earthquake wave excitation.
