A new adaptive vibration control of magnetorheological damper system and its application to washing machine

Abstract

Some undamped vibrations may cause undesirable behavior such as noise, overloads, excessive displacements, and early fatigue failures in the mechanical systems. Active vibration control is crucial for some of the mechanical systems such as washing machines. This article proposes a new vibration control strategy (VCS) for reduction of vibrations in washing machine. VCS utilizes adaptive nonlinear terminal sliding mode control (NTSMC) of double coil shear mode magnetorheological (MR) dampers and DC-DC buck converter. To achieve this goal, a control mechanism was designed that consists of two loops. The first loop implemented a force feedback control using proportional integral (PI) control and load cells. The second loop consists of adaptive NTSMC that was applied on buck converter to control current flow in MR dampers. The control law and finite convergence time to the equilibrium point were guaranteed for the current error using NTSMC. Moreover, an adaptive law was incorporated in NTSMC for the dynamic current control of MR dampers. The stability analysis of adaptive NTSMC was carried out using Lyapunov stability theory. An experimental setup was established for VCS that helps to study the performance of washing machine. A comparative analysis is presented for VCS with the passive dampers and other vibration control techniques that are reported in literature for washing machines.