Simulation of MacPherson strut side force reduction and influence in the dynamics of vehicle in Adams

The purpose of this degree work is to analyse side force reduction on the upper mount of a McPherson automotive front suspension, assembled on a vehicle. Adams software was used as it allows simulating a vehicle on realistic driving conditions and calculates the forces on a vehicle (points/joints). By changing the inclination of the spring axis with respect to the shock absorber axis, numerous analyses were made considering various driving conditions, all attributable to operations that a driver can access during normal use of the car. Parametric modeling software was used to change the inclination of the spring with respect to the shock absorber, which made it possible to obtain the hypothetical variants, considering the physical limits imposed by the geometry of the suspension itself. Starting from the original situation, the spring tilted in two different directions, one in the direction of the outside of the car and one inward. And for each direction different stages have been considered, in order to have a more accurate measurement of the influence of the inclination. A variation of trajectory was therefore considered following the directives ISO 3888-2: 2011that define the Moose Test, a test during braking and the passage of the car on an artificial bump (Presidential Decree 495/1992, as modified by Presidential Decree 610/96, in Art. 179. (Art. 42 Cod. Str.) Paragraph 5). The values relating to the dynamic behaviour of the vehicle and the relative displacements of the upper top mount of the suspension were extrapolated, in addition to the value of the lateral force acting on it. The results obtained with modified inclination angle are compared with the original configuration which allowed establishing the correct inclination to obtain significant decrease in lateral force and then subsequently an optimization of the results obtained. Subsequently, the use of a ball joint on the top mount strut was introduced to verify the influence of this joint on vehicle dynamics, displacements and lateral force in order to determine whether this modification will improve the parameters considered.