Characterization and modeling of a novel electro-hydraulic variable two-terminal mass device

Abstract

Much effort has been devoted to developing variable stiffness and variable damping devices for semi-active structural vibration control. However, little research has been done for variable inertial mass mainly caused by the mechanical terminal limit of the mass component. Based on the two-terminal mass scheme, we propose an electro-hydraulic approach to realizing a novel device with variable two-terminal mass. In this study, the flywheel that is traditionally handled by one physical terminal is manipulated by two terminals of a hydraulic cylinder-control-motor system. The transmission ratio of the system is adjusted using an electro-hydraulic proportional valve. Through modeling the ideal dynamic behavior, it is confirmed that the equivalent inertial mass between two terminals of the component can be made variable. To further understand its mechanical characteristics, a prototype device is developed and tested on a test rig. Triangular and sinusoidal excitation signals are employed respectively to identify the model parameters. The results show that the proposed model can describe the dynamic characteristics of the variable two-terminal mass device well. The proposed design and modeling schemes pave the way towards the semi-active variable inertial mass control of vibration systems.