Multibody modeling of a rear multilink suspension : dynamical analysis of the rubber bushings

The first role of a vehicle suspension aims to keep as much as possible a contact between the wheel and the road to transmit the driving force to the ground. Nowadays, with the evolution of technologies, the suspensions also have a great role for the comfort of the passengers. By their design, engineers seek to reduce noise and vibration transmission. Recent cars use among others multi-link suspensions. In this type of suspension the use of small elastic elements, the rubber bushings, has become widespread. They have the role of noise and vibration absorber but also they are necessary to avoid the hyperstaticity of the system. This master's thesis proposes a rather complete multibody modeling of a marketed car (performed with the help of Robotran©): from the chassis to the front double wishbone and rear multi-link suspensions with the details of all the links and arms without forgetting the wheel-tire assembly. Special attention is paid to the modeling of the rear suspension and the bushings, their representation in the MBS software as well as their constitutive laws. A model validation is done in comparison with theoretical values and a K&C test. Finally, this master’s thesis studies the dynamic behavior of the rear multi-link suspension and in particular of the bushings during a speed bump.