Vibration and Shock Isolation Performance of a Semi-Active “On-Off” Damper

The concept of an “on-off” damper employing the feedback signals from directly measurable variables is proposed. A control scheme utilizing the directly measurable relative position and relative velocity signals to produce the command signal is configured. The on-off damping mechanism can be achieved through the modulation of orifice area in a conventional hydraulic damper, using a two position on-off valve driven by the command signal. The shock and vibration isolation characteristics of the proposed on-off damper are evaluated through computer simulations. The shock and vibration isolation performance characteristics of the proposed damper are compared to the performance characteristics of a passive and an on-off damper utilizing the feedback from absolute and relative velocity signals.