The aim of the present work is to propose an innovative magnetorheological fluid-elastomeric damper which is applied to small amplitude vibration reduction occasions, especially for helicopter rotor. The damper is compact in structure and possesses the controllable dynamic characteristics. The magnetic circuit structure of the damper is designed and optimized emphatically in order to ensure its rationality. After the completion of the prototype, the damper is tested by a hydraulically actuated dynamic testing system under different excitation amplitudes, excitation frequencies, and input currents. Subsequently, a new phenomenological model is established to describe the nonlinear behavior of the proposed magnetorheological fluid-elastomeric damper. A series of parameter identification is conducted to fit both this model and Bouc–Wen model to experimental data for the purpose of verifying the accuracy of the established model.

To overcome the shortcomings of the Bouc–Wen model, such as too many parameters, complex identification process, and long time consuming, the sensitivity of parameters was analyzed. A Bouc–Wen optimum model with sensitive parameters to guarantee calculating accuracy was established. First, according to the results of the magnetorheological damper’s mechanical property test, the sensitivity of Bouc–Wen model’s parameters was analyzed by the one-at-a-time method. Optimization of the Bouc–Wen model was completed. Second, the parameters of the Bouc–Wen optimum model were identified under three harmonic excitations. Compared with the original Bouc–Wen model, the differences of calculation accuracy were 0.0055, 0.0007, and 0.0070 respectively. And the convergence rate of the fitness function for parameter identification increased by 67.89%, 49.94%, and 67.24%, respectively. And the iteration time of 1000 iterations was shortened by 36.52%, 25.95%, and 64.11%, respectively. It indicates that the Bouc–Wen optimum model had higher efficiency and certain accuracy in parameter identification process. Then, the calculation accuracy of Bouc–Wen optimum model with independent and coupled mean parameters were analyzed respectively. Finally, the parameters of the Bouc–Wen optimum model and current were fitted by the least square method. The results showed that the Bouc–Wen optimum model can accurately and efficiently simulate the dynamic characteristics of magnetorheological dampers.

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The aim of the present work is to develop an magnetorheological (MR) seat suspension for military vehicles to mitigate dynamic responses of seated occupant in both shock and vibration occasions. The main components of the MR seat suspension are tested and modelled. Subsequently, a mathematical model incorporating the MR seat and a seated occupant is established. The vibration and shock simulations based on the established model are carried out, and the results indicate that the proposed MR seat suspension can significantly alleviate the acceleration responses of the seated occupant under vibration input, and simultaneously possess the ability of reducing the spinal injury risk in the presence of severe impact. The systematic experiments of the MR seat prototype with a 50th percentile male hybrid III dummy are conducted, it is found out that the experimental results are in good agreement with the theoretical simulation results, which demonstrates that the developed MR seat suspension is provided with favourable vibration reduction performance and impact resistance.

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