Potential vibration isolation qualities of suspensions with two-step stiffness control in oscillation cycle

Abstract

The article dwells upon the detection of potential vibration isolation qualities of suspensions with a two-step stiffness control during the oscillation cycle using the example of a single-mass oscillating system. There are two principal schemes of two-step stiffness change of a vehicle suspension: a suspension with constant step stiffness and a suspension with variable step stiffness. A comparative study of vibration isolation qualities of a single-mass oscillating system with a two-step stiffness control, which corresponds to the abovementioned principal schemes was conducted. As a result of the conducted study, the optimal parameters of suspensions were detected, which ensure the stoppage of the sprung mass during a half of the oscillation cycle when the system goes out of the state of equilibrium and when there is no kinematic and dynamic disturbance effect. Besides, the optimal parameters of suspensions were further detected, which ensure the minimum deviations of the sprung mass from the neutral position corresponding to the soft suspension at the kinematic sinusoidal input. It was found that the suspension which is based on the diagram of two-step stiffness change of a suspension with constant step stiffness, provides for higher vibration isolation qualities, when used in a single-mass oscillating system as compared to the conventional uncontrolled suspension and suspension which is based on a two-step stiffness change diagram of suspension with variable step stiffness. The issue of high-frequency oscillation of a springing element as a result of a switch from higher stiffness to lower stiffness was noted.