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In this paper, a computational model of conventional engine mounts for commercial vehicles comprising elastic, viscous and friction functional components, which expresses the nonlinear behaviour of the dynamic stiffness and damping of mounts as functions of both frequency and amplitude of excitation, is developed. Optimisation approach is implemented to identify model parameters using measurement data. The developed model has been validated against measurement data for harmonic excitations with a frequency range of 5-100 Hz and an amplitude range of 0.025-2 mm employing three different engine mounts used in heavy trucks. The model shows good and admissible agreement with measurement data keeping the tolerance of estimation below 11%. Simulations of engine vibration dynamics are presented with both proposed model and commonly applied Kelvin-Voigt model of the mounts. The developed model can be used in complete vehicle advanced dynamic analyses and also in the design of semi-active and active engine mounting systems for commercial vehicles.

The main focus in the presented work is on the sensitivity analysis of the comfort and handling characteristics of a commercial vehicle with Individual Front Suspension (IFS). For the sensitivity analysis, two simulations in frequency domain are conducted: road input and steering input frequency responses. Employing the model of the tractor semitrailer combination for the above mentioned analyses, this study evaluates the influence of five damping coefficients — cab, front and rear axle shock absorbers — on our objectives. The results that are provided in Pareto fronts clearly show the great influence of the studied parameters, particularly the front axle and cab lateral dampers, on the vehicle comfort and handling for the performed simulations. Finally, the model is updated with the chassis and cab lateral damper coefficients to run a simulation on random roads for more detailed comfort examinations. This analysis confirms the obtained improvements in the outcome of the sensitivity study.