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This paper presents an analytical and experimental analysis of the characteristics of a squeeze-type magnetorheological (MR) mount which can be used for various vibration isolation areas. The concept of the squeeze-type mount and details of the design of a squeeze-type MR mount are discussed. These are followed by a detailed description of the test set-up for evaluating the dynamic behaviour of the mount. A series of tests was conducted on the prototype mount built for this study, in order to characterize the changes occurring as a result of changing electrical current to the mount. The results of this study show that increasing electrical current to the mount, which increases the yield stress of the MR fluid, will result in an increase in both stiffness and damping of the mount. The results also show that the mount hysteresis increases with increase in current to the MR fluid, causing changes in stiffness and damping at different input frequencies.

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To illustrate the vibration characteristics of the defective bearing more precisely, a dynamic model considering the detailed motion of the roller and the impact between the roller and the cage when the roller passes through the defect has been proposed. It overcomes the shortcomings of the previous models in which the roller's and cage's rotational speeds are set as constant values. The proposed model considers the detailed motion of the roller and the impact between the roller and the cage when the roller passes through the bearing defect. The validity and accuracy of the proposed model were verified by an experimental study. The motion characteristics, force characteristics, and vibration characteristics, when the roller passes through the defect, are analyzed. In addition, the vibration signals of the roller passing through two different types of defects are studied. The results show that the roller's rotational speed suddenly increases and the fluctuation amplitude of the revolution speed increases when the roller exits from the large defect. The large defect leads to high-frequency unstable collisions between the roller and the defective raceway. In addition, the slip velocity and the friction force between the roller and the raceway intensify the collision amplitude and generate high-frequency components of the vibration signal. They will also lower the frequency of the roller passing through the outer raceway, especially under high speed and light load conditions. The slipping and the restress between the roller and the defected raceway lead to small variations and big shocks in the vibration acceleration signal, respectively. These phenomena demonstrate the necessity of considering the detailed motion of the roller and the impact between the roller and the cage in the dynamic model.