When modeling the dynamic behavior of a vehicle with a flexible chassis, it is often necessary to model the deformation of the chassis in order to obtain accurate simulation results. Typical solutions for managing the deformation of the chassis require a trade-off between model simplicity (e.g. lumped mass models) and model realism (e.g. multi-body models). In this work, a different approach for modeling the chassis is proposed where the chassis is permitted to deform in bending and torsion similar to how a real chassis would. The proposed chassis model is a simple finite element model of the chassis which offers realistic deformations with relatively low computational requirements.
The proposed chassis model manages vertical and lateral bending deformations as well as torsional deformation. The parameters needed to define the model can be obtained through simple tests conducted on the vehicle to be modeled or through evaluation of the virtual chassis if the vehicle is still in the conceptual stage. The fidelity of the model can also be easily adjusted by the user to suit the modeling goals. Finally, the modeling methodology provides error estimates which can be used to evaluate the model at each time step to determine whether the chassis deformation needs to be reevaluated or if the results obtained from the previous time step's evaluation are sufficiently accurate to continue with the vehicle dynamics simulation.