Denisenko

The paper presents differential equations of vehicle’s motion at the moment of gear shifting during ascent or descent of a vehicle. The influence of time of gear shifting on the value of vehicle's speed variation and generalized parameter – the actual interval of revolution of transmission’s drive portion in cases of gear shifting to the speed-increasing or speed-reducing gear. Analytical dependences between the size of the actual interval of revolution, parameters of the gear box, car and external resistance factors were obtained. Conclusions regarding the influence of the actual interval of revolution on the output parameters of transmission and vehicle were drawn.

The article systematizes information about characteristics of snow cover significantly influencing cross-country ability, movability, mobility, energy efficiency and other properties of the vehicles. The authors provide equations of the most important communication parameters of snow cover condition, such as density, hardness, rigidity, cohesion, coefficient of internal friction, moisture, temperature, relative deformation, shear which are obtained from experimental data. Basing on the analysis of these dependencies the authors specify existing models of snow which are used to describe interaction of an engine with its support base.