Vibration Isolator with Quasi-Zero Stiffness Characteristics and High Load-Carrying Capacity

A vibration isolator is proposed using a simple QZS combination of the extension and compression springs. A parameter study is conducted to determine the relationship between the QZS performance and the design parameters of the spring and linkage. Notably, the QZS convergence and load-carrying capacity are significantly affected by both the spring and linkage parameters. A prototype of a QZS vibration isolator is developed and its performance is experimentally validated through the displacement transmissibility under base excitation. Notably, the QZS characteristics significantly reduced vibrations for a whole range of the excitation frequency and also suppressed vibrations around peaks by as much as 70%. The vibration isolation is expected to be further enhanced by reducing errors caused in the manufacturing process of QZS springs.