Modeling and simulation of a hydraulic interconnected suspension system for automotive applications

The design of a vehicle’s suspension system has the main task to find the best trade-off between the handling capability of the vehicle and the ability to filter the road irregularities. Since the early stage of the automotive industry, different types of solutions have been introduced to maximize at same time both requirements and, one of these, are the passive interconnected suspensions that provide a linkage between the front and the rear axle. This work proposes a fluid-mechanical interconnected suspension system with the aim to uncouple the pitch and heave modes from the roll and warp ones, and to realize a soft warp mode. The initial part of the document presents a detailed description of the different archetypes presented up to now in the literature and in the industry, highlighting the tests and the results declared. Afterwards, the main part of the thesis project regarding the modelling of the fluid-mechanical system is illustrated with two different approaches: at first, a physical model is elaborated in Simscape environment; then, a simplified model is introduced with Simulink where the dynamics of the system is described by matrix equations. The analysis of the performance of the system has been carried out in co-simulation environment between Simscape/Simulink and Vi-CarRealTime package, where a comparison between a high-performance vehicle model in conventional configuration and with the interconnected suspensions is evaluated in standard manoeuvres and in lap time simulations.