Semiactive sliding-mode control of the unbalance response in a rotor-bearing system supported on MR dampers

This paper deals with the problem of semiactive balancing control of a rotor-bearing system, where one journal bearings is supported on two radial magneto-rheological (MR) dampers. The mathematical model of the rotor-bearing system results from a Jeffcott-like model and the dynamics associated to the MR dampers, whose Theological properties depend on the current inputs. For control purposes we use the Choi- Lee-Park polynomial model for the MR dampers, which is quite consistent with the nonlinear and complex hysteresis behavior and also simplifies the physical implementation on an experimental setup. The semiactive control scheme for the unbalance response of the rotor-bearing system is synthesized using sliding-mode control techniques. Some numerical and experimental results are included to illustrate the dynamic performance and robustness of the overall system.