Динаміка підресореної частини КТЗ і стійкість руху

Abstract

The article investigates the influence of longitudinal-angular vibrations of the sprung mass of wheeled vehicles (WV) with nonlinear characteristics of the suspension system and kinematic parameters of move-ment along the curved sections of the road on the stability of WV. The main results of the work were obtained using the equations of kinetic statics, a mathematical model of relative nonlinear longitudinal-angular oscillations of the sprung mass (SM), based on the analysis of the quantitative and qualitative influence of the main force parameters of the suspension system (SS) and the determining parameters of longitudinal-angular oscillations of the SM on the level of interaction of the tires with the road coating. The critical speed of steady movement of the vehicle is determined as a function of the geometric and power parameters of the SS, the characteristics of the road surface, and the amplitude of longitudinal and angular oscillations. The numerical analysis of obtained ratios has shown that the critical values of steady motion speed for the skidding of the WV along the curved sections of the road are different: a) a larger value of the amplitude of SM oscillations corresponds to a smaller value of the critical speed of steady motion; b) it is significantly overestimated if the longitudinal and angular fluctuations of the sprung mass are not taken into account; c) the value is bigger for WV with the progressive force characteristic of the shock absorbers at small amplitudes of oscillations compared to the linear force characteristic (under the condition of equality of static deformation), and vice versa for the “large” ones; d) the value for the regressive force characteristic of elastic shock absorbers at small amplitudes of oscillations is smaller than for the linear characteristic of the shock absorbers, and the opposite for the “large” ones; e) the critical value of the speed of steady motion is bigger for the progressive characteristic of elastic shock absorbers at larger values of the static deformation of the SS and, on the contrary, it is smaller for the regressive one. The obtained results can be used for the designing or modernization of suspensions and well as a basis for development of a new software product for the controlled suspension systems. They coincide in the limiting case with those known in the scientific literature, which confirms their credibility. Keywords: Oscillations of sprung mass, amplitude, frequency, critical speed of steady motion.