Mohammad Miah

Research

Semi-active Control for Magnetorheological (MR) Dampers using Sliding Mode Control (SMC) & System Identification (SI) Methods
Mitigation techniques for the effects of dynamic loading such as seismic or wind vibrations form a crucial area in the field of structural engineering. The complexity of the topic is increased due to the nonlinear (dynamic) analysis and design that are required. Usually, the underlying mathematical/simulation model and the real structure response may not be on par because of the inherent uncertainties and naturally the feature of nonlinearity. )In fact the common case is that the dynamic characteristics of actual civil structures are not identical to those of the evaluation model originally developed, and on top of that they are prone to change due to external factors. For instance the natural frequencies of a structure may vary significantly as a result of temperature variations. Therefore, in order to successfully monitor the system, proper identification techniques are of the essence. The main focus of this research is firstly to achieve the monitoring of a Magnetorheological (MR) damping system by using On-Line System Identification (SI) techniques, such as the Kalman filter (KF), and employing an appropriate model for the hysteretic behavior, namely the Bouc-Wen model. Subsequently, the recorded data will be applied for the updating of the underlying finite element model used to describe the structural system. Furthermore, a sliding mode control (SMC) algorithm will be employed in order to satisfy the stability condition of the system and calculate the feedback control force for the MR damper.

Publications while at ETH