Experimental Validation of Vibration Isolation in Quasi-Zero Stiffness Mount Concept

In the mounting of vibration sources and receivers, it is typically desirable to have low stiffness for isolation. On the other hand, durability may demand a high stiffness to handle large inputs without excessive motion, which seems like a contradictory requirement. Both may be achieved using nonlinear stiffness mounts which make use of elastomer deformation to exhibit softening through geometric nonlinearity. This paper discusses a physical proof of concept for a quasi-zero stiffness mount design with a three-regime stiffness curve including a preload, isolation, and motion control regions. Building on a design concept proposed in prior literature, new experimental validation is obtained for the prior nonlinear static stiffness property, which is then fit into a more stable mount topology. Fabrication and material issues are also discussed. Finite element models are used with material coupon tests to characterize the elastic properties of chosen materials, as well as predicting the stiffness behavior of the mount. Computational models are also used along with sinusoidal vibration measurements to assess the effect of damping, which is quantified with structural, viscous, and fractional calculus based damping models. Experimental validation of the new configuration is provided for both static and dynamic excitations.