Adaptive backstepping based MR damper monitoring for structural applications
Ali, S. F. and Adhikari, S.,
SPIE Smart Structures, Materials, Nondestructive Evaluation and Health Monitoring Conference,
San Diego, California, USA, March 2010.
Magnetorheological (MR) dampers are intrinsically nonlinear devices, which make the modeling and design of a suitable control algorithm for MR damper monitoring an interesting and challenging task [1]. To evaluate the potential of magnetorheological (MR) dampers in control applications and to take full advantages of its unique features, a mathematical model to accurately reproduce its dynamic behavior has to be developed and then a proper control strategy has to be taken that is implementable and can fully utilize their capabilities as a semi-active control devices.
To this date most widely used MR damper model is the Bouc-Wen hysteretic model [2]. The parameters of the hysteretic model are usually identified through various pseudo-dynamic testing of the damper. Therefore, dependence of the parameters on damper dynamics (i.e., displacement and velocity) is neglected. Recent studies have shown that this negligence is not minor and could lead to a catastrophe especially for large MR dampers [3].
The present paper focuses on both the aspects with the development of an adaptive backstepping based nonlinear current monitoring of MR dampers for semi-active control of structures under earthquakes is developed. Adaptive backstepping estimates the parameters of the MR damper in online and also provides a stable nonlinear magnetorheological damper current monitoring directly based on system feedback such that current change in magnetorheological damper is gradual. Unlike other MR damper control techniques available in literature, the main advantage of the proposed technique lies in its current input prediction directly based on system feedback and smooth update of input current. Furthermore, while developing the proposed semi-active algorithm, the dynamics of the supplied and commanded current to the damper is considered, which is neglected in earlier studies. The efficiency of the proposed technique is shown taking a base isolated three story building under a set of seismic excitation.
1. Ali Sk. F. and Ramaswamy A., 2009, "Testing and modeling of MR damper and its application to SDOF systems using integral backstepping technique," J. Dynamical Systems, Measurements and Control, 131(2):021009.
2. Spencer, B. F., Jr., Dyke, S. J., Sain, M. K., and Carlson, J. D., 1997, "Phenomenological Model for Magnetorheological Dampers," J. Eng. Mech., 123, pp. 230-238.
3. Yang, G., Spencer, B., Jung, H. H., and Carlson, J. D. J., 2004, "Dynamic Modeling of Large-Scale Magnetorheological Damper Systems for Civil Engineering Applications," J. Eng. Mech., 130, pp. 1107-1114.
BiBTeX Entry
@inproceedings{cp78,
AUTHOR={S. F. Ali and S. Adhikari},
TITLE={Adaptive backstepping based MR damper monitoring for structural applications},
BOOKTITLE={SPIE Smart Structures, Materials, Nondestructive Evaluation and Health Monitoring Conference},
YEAR={2010},
Address={San Diego, California, USA},
Month={March},
note = {accepted}
}
by Sondipon Adhikari