Dynamic Contribution of Tires in Vehicle Suspension Modeling: An Experimental Approach
An analytical-experimental approach is followed to obtain the dynamic model of a car vehicle, taking into account the full dynamic contribution due to tires. Linearized and condensed vehicle equations of motion are first introduced. The experimental modal model of a car tire, consisting of limited sets of eigenfrequencies and eigenshapes is then experimentally estimated in the frequency range Δftire=0÷300 Hz, starting from a restricted set of experimental degrees of freedom (d.o.f.). The tire is locally loaded to simulate the displacements due to gravitational loads and road contact occurring in operating conditions. Elastic coupling between the car structural model and the tire modal model is thus obtained; a linear, complex eigenproblem is thus formulated, and eigenfrequencies related to the full system are obtained as well. Results are reported and discussed in detail.