Experimental analysis and optimization of driving smoothness simulation of the SUV vehicle based on ADAMS/car

Abstract Sport utility vehicles (SUVs) often encounter challenges in simultaneously balancing handling stability and ride comfort when driving on rough roads. In order to ensure driver safety and improve ride comfort, this study utilizes the multibody dynamics simulation software Automatic Dynamic Analysis of Mechanical Systems (ADAMS) to build a comprehensive vehicle dynamics model of a family SUV. Initially, a front suspension parallel wheel hop test and a rear suspension reverse wheel hop simulation test are conducted to verify the accuracy of the suspension simulation models. Subsequently, simulation analyses of the complete vehicle’s handling stability under steady-state cornering conditions and driving smoothness under random road excitations are performed. Finally, the Latin hypercube experimental design method in ADAMS/Insight is adopted to conduct 256 sets of multi-objective optimization iterative simulations on the stiffness and damping parameters of the front and rear suspensions. In response to the reviewers’ comments, the optimization target is clarified as the total frequency-weighted acceleration RMS used for ride-comfort evaluation, rather than an unsupported linear weighting of the three vibration components. The 60 km/h Class B-road condition is also defined as the nominal design condition, while the other speeds are interpreted as off-design robustness checks rather than evidence of global Pareto optimality over the complete speed range. The experimental and simulation results indicate: (1) The established multibody dynamic model effectively simulates the structural and mechanical constraints of the actual vehicle. Key alignment parameters, including kingpin inclination angle, kingpin caster angle, camber angle, and toe angle of the front suspension, are all within the permissible design ranges. Furthermore, the relative errors for the rear suspension stiffness and roll center height are both within 3%, effectively reflecting the real vehicle’s operational status. (2) The optimized suspension parameters improve the ride comfort of the SUV, achieving a maximum observed 39.9% reduction in the total weighted acceleration RMS at 100 km/h in the reported simulation case. The handling-stability indices change only slightly after optimization: the steering gradient changes from $$U=-23.912$$ to $$U=-24.081$$ and the roll angle gradient from $$K_{\varphi }=3.862$$ to 3.861. However, because the negative steering-gradient values indicate an oversteer tendency under the adopted sign convention, the optimization should be interpreted as preserving the reported handling indices within this simulation condition rather than resolving the baseline oversteer characteristic.