Influence of fluid inerter nonlinearities on vehicle suspension performance

An ideal inerter has been widely used in various vibration isolation fields. Due to its mechanical construction, some nonlinear properties of the inerter need to be taken into consideration. This article concerns the nonlinearities of the fluid inerter and its impact on vehicle suspension performance. A complete nonlinear dynamic model of the fluid inerter is introduced, and the sensitive analysis of the designed parameters is studied. Comparing to the traditional passive suspension, the vehicle suspension performances of three different suspension layouts incorporating the nonlinear fluid inerter are investigated at different velocities and different spring stiffness. Furthermore, the influences of the nonlinearities in frequency domain are also noted. Results show that the nonlinear properties of the fluid inerter have a great effect on vehicle suspension performance except S2 suspension. The impact is more significant in low frequency domain of the vibration.