Nonlinear Structural Control Using Magnetorheological Damper

Author(s):  
Shaikh Faruque Ali ◽  
Ananth Ramaswamy

This chapter provides an introduction to semi active control of base isolated buildings using magnetorheological (MR) dampers. Recently developed nonlinear control algorithms are discussed. First a fuzzy logic control (FLC) is designed to decide how much voltage is required to be supplied to the MR damper for a desired structural response. The FLC is optimized using micro genetic algorithm. A novel geometric approach is developed to optimize the FLC rule base. Experiments are undertaken to access the efficacy of the optimal FLC. Secondly the chapter develops two model based control algorithms based on dynamic inversion and integrator backstepping approaches. A three storey base isolated building is used for experimental and numerical studies. A numerical comparison is shown with clipped optimal control.

2015 ◽  
pp. 211-244
Author(s):  
Shaikh Faruque Ali ◽  
Ananth Ramaswamy

This chapter provides an introduction to semi active control of base isolated buildings using magnetorheological (MR) dampers. Recently developed nonlinear control algorithms are discussed. First a fuzzy logic control (FLC) is designed to decide how much voltage is required to be supplied to the MR damper for a desired structural response. The FLC is optimized using micro genetic algorithm. A novel geometric approach is developed to optimize the FLC rule base. Experiments are undertaken to access the efficacy of the optimal FLC. Secondly the chapter develops two model based control algorithms based on dynamic inversion and integrator backstepping approaches. A three storey base isolated building is used for experimental and numerical studies. A numerical comparison is shown with clipped optimal control.


Author(s):  
Jagadish G. Kori ◽  
R.S. Jangid

Magnotorheological (MR) dampers have been demonstrated to be more effective in reducing the structural response due to earthquakes using only a small amount of external power. The performance of MR damper depends upon type of control law used and the damper force is directly depends on the input command voltage. The purpose of this study is to evaluate the effectiveness of input command voltage on MR damper system against recently proposed control laws under different earthquakes. The magnitude of control force increases with the increase in the input command voltage of MR damper, however for the different damper locations and configurations maximum command voltage to the current driver may not always effective in reducing the structural responses. To investigate the effective performance of the MR dampers, different control algorithms with multiple MR damper locations are considered in this study. A phenomenological model of a shear- mode MR damper, based on a Bouc–Wen element, is employed in the analysis of the controlled building. The control algorithms are tested on a five-story framed building and parametric study on variation in the input command voltage is conducted for different real earthquake ground motions. The numerically evaluated optimum parametric values are considered for the analysis of the different damper locations in the building in order to reduce the displacement, acceleration and the base shear of the building. It is shown numerically that the performance of the MR damper has a great potential in suppressing structural vibrations over a wide range of seismic inputs by selecting appropriate optimum input command voltages.


Author(s):  
Omar Mahmoud Elmeligy ◽  
M. H. M. Hassan

Smart structural control is now emerging as an alternative to conventional earthquake resistant design and traditional structural control techniques. Fuzzy logic based control is one of the promising smart control strategies that could be used for this function. Magneto Rheological (MR) dampers are considered one of the promising semi-active control devices that can be used to control the structural response of buildings under earthquake excitation. The properties of MR dampers can be controlled using several smart techniques such as Fuzzy Logic. In this paper, a comparative analysis is conducted to investigate the most optimum location for placing MR dampers, which are controlled by Fuzzy Logic, in a three-degree-of-freedom benchmark problem. The study explores three potential schemes for allocating and operating MR dampers within the system under consideration. Two main structural response parameters are considered in this study, maximum displacement and maximum acceleration. In addition, the study investigates the lowest number of fuzzy-controlled MR dampers that are required in order to produce the required structural behaviour. This is an initial step towards the development of a generic allocation algorithm that is capable of identifying the required number of MR dampers, and their location, for controlling any multi-degree-of-freedom system.


2019 ◽  
Vol 3 (1) ◽  
pp. 118-126 ◽  
Author(s):  
Prihangkasa Yudhiyantoro

This paper presents the implementation fuzzy logic control on the battery charging system. To control the charging process is a complex system due to the exponential relationship between the charging voltage, charging current and the charging time. The effective of charging process controller is needed to maintain the charging process. Because if the charging process cannot under control, it can reduce the cycle life of the battery and it can damage the battery as well. In order to get charging control effectively, the Fuzzy Logic Control (FLC) for a Valve Regulated Lead-Acid Battery (VRLA) Charger is being embedded in the charging system unit. One of the advantages of using FLC beside the PID controller is the fact that, we don’t need a mathematical model and several parameters of coefficient charge and discharge to software implementation in this complex system. The research is started by the hardware development where the charging method and the combination of the battery charging system itself to prepare, then the study of the fuzzy logic controller in the relation of the charging control, and the determination of the parameter for the charging unit will be carefully investigated. Through the experimental result and from the expert knowledge, that is very helpful for tuning of the  embership function and the rule base of the fuzzy controller.


1985 ◽  
Vol 9 (4) ◽  
pp. 224-227 ◽  
Author(s):  
Mohamed Abdel-Rohman

The time delay between measuring the structural response, and applying the designed active control forces may affect the controlled response of the structure if not taken into consideration. In this paper it is shown how to design the control forces to compensate for the delay effect. It is also shown that the time delay effect can be used as a criterion to judge the effectiveness of the proposed control mechanism. As an illustration of the theoretical consideration, a numerical example in which a tall building is controlled by means of active tendons is presented.


2013 ◽  
Vol 2013 ◽  
pp. 1-10 ◽  
Author(s):  
Aly Mousaad Aly

This paper presents vibration control of a building model under earthquake loads. A magnetorheological (MR) damper is placed in the building between the first floor and ground for seismic response reduction. A new control algorithm to command the MR damper is proposed. The approach is inspired by a quasi-bang-bang controller; however, the proposed technique gives weights to control commands in a fashion that is similar to a fuzzy logic controller. Several control algorithms including decentralized bang-bang controller, Lyapunov controller, modulated homogeneous friction controller, maximum energy dissipation controller, and clipped-optimal controller are used for comparison. The new controller achieved the best reduction in maximum interstory drifts and maximum absolute accelerations over all the control algorithms presented. This reveals that the proposed controller with the MR damper is promising and may provide the best protection to the building and its contents.


2008 ◽  
Vol 56 ◽  
pp. 218-224
Author(s):  
Maguid H.M. Hassan

Smart control devices have gained a wide interest in the seismic research community in recent years. Such interest is triggered by the fact that these devices are capable of adjusting their characteristics and/or properties in order to counter act adverse effects. Magneto-Rheological (MR) dampers have emerged as one of a range of promising smart control devices, being considered for seismic applications. However, the reliability of such devices, as a component within a smart structural control scheme, still pause a viable question. In this paper, the reliability of MR dampers, employed as devices within a smart structural control system, is investigated. An integrated smart control setup is proposed for that purpose. The system comprises a smart controller, which employs a single MR damper to improve the seismic response of a single-degree-of-freedom system. The smart controller, in addition to, a model of the MR damper, is utilized in estimating the damper resistance force available to the system. On the other hand, an inverse dynamics model is utilized in evaluating the required damper resistance force necessary to maintain a predefined displacement pattern. The required and supplied forces are, then, utilized in evaluating the reliability of the MR damper. This is the first in a series of studies that aim to explore the effect of other smart control techniques such as, neural networks and neuro fuzzy controllers, on the reliability of MR dampers.


Author(s):  
S. J. Dyke ◽  
B. F. Spencer ◽  
M. K. Sain ◽  
J. D. Carlson

Abstract In this paper, the efficacy of magnetorheological (MR) dampers for seismic protection of structures is investigated through a series of experiments in which an MR damper is used to control a three story test structure subjected to a one-dimensional earthquake motion. Because of the intrinsic nonlinearity of the MR damper, several earthquake amplitudes are considered to investigate the performance, in terms of both peak and rms responses, of this control systems over a range of loading conditions. The results indicate that the MR damper is quite effective for structural response reduction over a wide class of seismic excitations.


2005 ◽  
Vol 13 (3) ◽  
pp. 345-355 ◽  
Author(s):  
Gang Jin ◽  
M.K. Sain ◽  
B.E. Spencer

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