Adaptive parameter identification of Bouc-wen hysteresis model for a vibration system using magnetorheological elastomer

Abstract

The Bouc–wen hysteresis model has been widely used to design systems using magnetorheological (MR) materials. However, the model parameters cannot be perfectly determined due to the magnetic-field dependency and unmeasurable states. In this study, a novel adaptive parameter identification method is proposed for a model consisting of three components: an estimated model, a hysteresis observer, and adaptive algorithms. While the estimated model refers to the experimental data and adjusts the parameters directly to their actual values, the hysteresis observer is constructed to portray the unmeasurable hysteretic force that is based on the observer dynamic and misalignment. The proposed adaptive algorithms updated the parameters to actual values based on stability and adaptation theory. The Bouc–wen model, whose parameters were determined by the proposed method, captured the MR elastomer (MRE) characteristics well at different frequencies, amplitudes, and magnetic field strengths. The method was further studied to determine the parameters of a nonlinear vibration structure equipped with an MRE-based isolator. Asymptotic stability in response tracking and robustness in dynamic excitation were demonstrated using this theory. The method was characterized by fast convergence and simple calculations that facilitate the design of vibration control systems with uncertain parameters and hysteretic state. A comparison between the simulation and experimental results proved the effectiveness of the proposed method.