Simulation modeling of field movement of four-wheel drive vehicles in the MATLAB Simulink software environment

Abstract

The work presents the developed simulation model of the movement of universal wheeled vehicles of the Mercedes-Benz Unimog type, which combines both the functions of a small wheeled tractor and a four-wheel drive truck for movement, including off-road, in the MATLAB Simulink software environment for technological operations (tillage) and in transport mode. Machines of this type were widely used in the post-war Europe and are relevant for Ukraine as well. The mathematical description of the interaction of wheels and attached equipment with the deformable soil surface is based on the so-called WES methodology of the US Army, which is generally accepted and outside NATO and is significantly different from the methodology adopted in the former USSR. Assessment of the physical and mechanical properties of the bearing surface on the basis of the so-called CI cone index, which is determined by standardized measurement of resistance to deformations with a cone-shaped penetrometer, will allow to more adequately model the processes of interaction of a wheel with a pneumatic tire with a deforming surface and, accordingly, more adequately implement as assessment of the adequacy of specific machine designs, as well as during design work of new machine models. In the process of design work on a low-tonnage four-wheel drive universal wheeled machine, which allows to perform both technological operations of soil cultivation (agricultural and communal spheres), and to ensure the transportation of goods, including in off-road conditions, the formation of the necessary range of gear ratios of the transmission, in particular the required values downshifts of the transfer box for both transport and technological modes of operation. This work is actually devoted to the formation of a corresponding simulation model of movement.