Nonlinear Vibration Control Device for a Vehicle Suspension Using Negative Stiffness Mechanism

Introduction Vibration suspension system is used in the automobiles to mitigate the excitations that can come from the travel over various road profiles. The conventionally used suspension systems are linear devices that are effective against high frequencies; however, they have limitations in isolation ability in the low-frequency ranges. Hence, nonlinear isolation system can be used to overcome such limitations. Methodology The quasi-zero stiffness (QZS) characteristics are efficient in the vibration isolation and can provide isolation efficiently against low-frequency excitations as well. This concept is taken into consideration and has designed a nonlinear vibration isolation system with QZS behaviour. The negative stiffness is achieved through the inclined spring arrangement, and the positive stiffness is obtained from the pneumatic system. The force-displacement model is used to develop the approximate dynamic modelling for small displacement. Results The performance is studied against various road profiles as per ISO 8608. The results showed that the isolation system effectively isolates the external excitations from the road profile and shows a high isolation capability in the higher velocities. The study shows the proposed system reduced on an average of 92% and 88% of external excitations in road class B-D and E-H, respectively. Conclusions Based on the computational study conducted in this work on the developed design, the isolation system is found to be effective in vibration isolation. The QZS system parameters highly influence the performance of the isolation system. The system developed in this work can be used to test for real-time automobile applications.