Semi-active MR Damper Research Articles

An Experimental Study of Semiactive Modal Neuro-control Scheme Using MR Damper for Building Structure

In this study, a semiactive modal neuro-control scheme which combines the modal neuro-control algorithm with a semiactive MR damper is proposed, and its effectiveness is experimentally verified through a series of shaking table tests. A modal neuro-control scheme uses modal coordinates as inputs of neuro-controller. Hence, it is more convenient to design the controller compared with conventional neuro-control schemes. A Kalman filter is introduced to estimate modal states from measurements. Moreover, the clipped algorithm is adopted to provide an appropriate command voltage to an MR damper. For shaking table tests, a scaled three-story shear building model is considered. Two types of semiactive modal neuro-controllers are trained with a reproduced El Centro earthquake for their own purposes. The performance of the proposed semiactive modal neuro-control scheme is compared with that of the passive-optimal case. In the experiments, the proposed semiactive modal neuro-controllers show better performance than the passive-optimal case, especially in adaptability over various excitations and reducing inter-story drifts as well as accelerations. Moreover, the proposed scheme can be designed for specific purpose which fulfills the designer's requirement (e.g., focusing on reducing inter-story drifts). Therefore, the proposed semiactive modal neuro-controller can be effectively used in reducing seismic responses of large engineering structures.

21712 ハードニング特性を有する受動型MRダンパと準能動型MRダンパの研究(動吸振器,OS.4 振動・音響の制振技術,学術講演)

21712 ハードニング特性を有する受動型MRダンパと準能動型MRダンパの研究(動吸振器,OS.4 振動・音響の制振技術,学術講演)

Vibration control of mechanical systems using semi-active MR-damper

The concept of structural vibration control is to absorb vibration energy of the structure by introducing auxiliary devices. Various types of structural vibration control theories and devices have been recently developed and introduced into mechanical systems. One of such devices is damper employing controllable fluids such as ElectroRheological (ER) or MagnetoRheological (MR) fluids. MagnetoRheological (MR) materials are suspensions of fine magnetizable ferromagnetic particles in a non-magnetic medium exhibiting controllable rheological behaviour in the presence of an applied magnetic field. This paper presents the modelling of an MR-fluid damper. The damper model is developed based on Newtonian shear flow and Bingham plastic shear flow models. The geometric parameters are varied to get the optimised damper characteristics. The numerical analysis is carried out to estimate the damping coefficient and damping force. The analytical results are compared with the experimental results. The results confirm that MR damper is one of the most promising new semi-active devices for structural vibration control.

SEMI-ACTIVE CONTROL OF RAILWAY VEHICLE STRUCTURE VIBRATION BASED ON MR DAMPER

Based on the flex-rigid multi-body system dynamics model of railway vehicle, the first vertical bend structure modal and vertical and pitch rigid vibration of carbody which reduce the ride quality are controlled using independent modal space control (IMSC) and optimum control theory. A semi-active control strategy using MR damper is proposed to decease the vibration acceleration of the vehicle on the floor, to improve the ride quality of railway vehicle, and to save the energy consumed. The co-simulation of the full vehicle mechanical and semi-active control system is finished in ADAMS and Mat lab//Simulink~(?) environment. The simulation results show that this semi-active control method according to shyhook damper control model is effective, the first bend structure modal of carbody is restrained and the vehicle running behaviour is improved. This semi-active MR damper used in railway vehicle can be designed.

Identification of semi-physical and black-box non-linear models: the case of MR-dampers for vehicles control☆

The topic of this paper is the identification of an accurate model for magneto-rheological (MR) dampers. A semi-active MR-damper is a dynamic system, where the inputs are the elongation velocity and the command current; the current is the control input which modulates at high-bandwidth the damping characteristic through the variation of a magnetic field. The output is the force delivered by the damper. Among the broad set of applications where MR-dampers can be used, the results proposed in this work refer to MR-dampers for the control of vehicle dynamics. MR-damper are highly non-linear systems, and their accurate modeling is a non-trivial task. MR-dampers can be modeled using two different model classes: semi-physical models and black-box models. Both approaches are considered in this work. The purpose of this brief paper is to make a concise but complete presentation and discussion of a non-trivial system identification problem . The problem considered herein is particularly interesting from the system identification point of view: from one side, the MR-damper is a very attractive actuator, which is likely to become the key device for many dynamics and vibration control systems in the near future; on the other side, it is an example of an application problem where the accurate modeling of the actuation device is one of the most crucial part of the whole control design problem.

FULLY ADAPTIVE SEMI-ACTIVE CONTROL OF VIBRATION ISOLATION BY MR DAMPER

This paper is concerned with a new fully adaptive control scheme for vibration isolation using a semi-active MR damper installed between ground and first floor, which is composed of two adaptive controllers. One is an adaptive inverse controller which can give necessary input voltage to MR damper so as to generate specified reference damping force to be acted on a controlled structure. The input voltage is decided using a nonlinear adaptive observer with identified model parameters of the MR damper which expresses hysteresis behavior of nonlinear dynamic friction mechanism of the MR fluid. The other is an adaptive reference controller which can match the dynamics of the first floor of structure to a reference dynamics. The proposed fully adaptive approach can cope with uncertainties in both models of MR damper and structure. Theoretical analysis and experimental results are also shown to validate its effectiveness.

Identification of semi-physical and black-box non-linear models: the case of MR-dampers for vehicles control

The topic of this paper is the identification of an accurate model for magneto-rheological (MR) dampers. A semi-active MR-damper is a dynamic system, where the inputs are the elongation velocity and the command current; the current is the control input which modulates at high-bandwidth the damping characteristic through the variation of a magnetic field. The output is the force delivered by the damper. Among the broad set of applications where MR-dampers can be used, the results proposed in this work refer to MR-dampers for the control of vehicle dynamics. MR-damper are highly non-linear systems, and their accurate modeling is a non-trivial task. MR-dampers can be modeled using two different model classes: semi-physical models and black-box models. Both approaches are considered in this work. The purpose of this brief paper is to make a concise but complete presentation and discussion of a non-trivial system identification problem. The problem considered herein is particularly interesting from the system identification point of view: from one side, the MR-damper is a very attractive actuator, which is likely to become the key device for many dynamics and vibration control systems in the near future; on the other side, it is an example of an application problem where the accurate modeling of the actuation device is one of the most crucial part of the whole control design problem.

Neural-Network Model of a Magneto-Rheological Damper

The topic of this paper is the identification of an accurate model for Magneto-Rheological (MR) dampers. A semi-active MR-damper is a dynamic system, where the inputs are the stroke and the command current; the current is the control input which modulates at high-bandwidth the damping characteristic through the variation of a magnetic field. The output is the force delivered by the damper. Among the broad set of applications where MR-dampers can be used, the results proposed in this work refer to a MR-dampers for the control of vehicle dynamics. MR-damper are highly-nonlinear systems, and their accurate modeling is a non-trivial task. MR-dampers can be modeled using two different model classes: semi-physical models and black-box models. Both approaches are considered in this work.