MULTIBODY SIMULATION OF SEMI-ACTIVE SUSPENSION SYSTEMS WITH SMART BALL JOINT

The purpose of this thesis is to investigate the multibody modelling and simulation of a semiactive suspension system with the use of a smart ball joint sensor. It measures longitudinal and lateral forces between the suspension systems. The new technology is designed to improve vehicle dynamics by automatically computing and applying the proper damping forces necessary to reduce roll angles while cornering, pitch during braking or accelerating when driving at drastically changing speeds. This thesis is detailed over five major chapters, and we start with the state-of-the-art and benchmarking of the semi- active and active suspension system benefits and applications. Next is the mechanical design and sensor phase, with the smart ball joint is endowed with sensors to accurately measure forces and communicates this data back to a state flow controller for adjusting the damping force. The core of the research is in the vehicle dynamics simulations which have been done with Adams Car multibody modelling. This includes standard dynamic manoeuvre like a step steer, single lane change, swept sine steer and braking tests performed on a virtual FIAT 500 setup. The simulations are important for determining the target values for reducing roll and pitch of the vehicle, which might be later used as basis for validating the performance of the semi-active suspension system. The Adams Car is co-simulated with the Matlab Simulink is also an important part of the study. This enables the implementation of a control logic which reacts to the data in real time from the outputs and inputs created. The state flow controller provided the necessary feedback of this force data in order to adjust the damping at any instance to improve stability and ride comfort. This thesis provides a plug and play solution to improve the vehicle dynamics by realizing the smart sensor technology in Suspension system. The virtual simulations and validation setup of FIAT 500 can be considered as the groundwork for future real-world applications, thereby it helps to better safety and comfort in automotive industries.