Vol 10, No 1 (2016)

The paper describes control system for multifunctional off-road transport with hydrostatic transmission movement at adverse terrain. Graphs of simulation results for developed machine are shown to select and justify the parameters, characteristics and adjustments of hydrostatic transmission.

The article presents an analytical review devoted to the design of combination of vehicles towing elements wheel drives in domestic and foreign automotive industry. Brief information regarding the developed mathematical model of linear dynamics for tractor unit with active towing element is given.

The paper gives an overview of mathematical descriptions of engine speed performance characteristics that are needed when simulation of “engine-automobile-driver-environment” systems. The analysis of models based on different classes of functions is given; its advantages and disadvantages are discussed. The regression model based on the use of functions closely related to the physics of investigated processes is proposed.

The paper makes hydraulic calculation of heat exchanger inlet manifold of engine with an external supply of heat.The estimation of uneven fluid flow through heat exchanger elements was made.

The possibility of efficient use of local air cooler in cabins as a means of normalization of the thermal state of opera- tors with regard to their sex, weight and changing environment of air temperature during the day is considered. It is shown that for the assimilation of different heat generation levels of maximum possible number of operators the per-formance of device over the air must have infinitely variable adjustment. At the same time, it is shown that external temperature changing does not require air supply regulation. The degree of cooling air in apparatus irrigated nozzle re- tains constant throughout the whole range of initial temperature and air flow variation.

The paper presents a mathematical model of shifting sleeve switching process used in interwheel and interaxal dif- ferential locking on off-road vehicles. The simulation model in MATLAB Simulink is created. The paper analyzes shifting sleeve switching process at different speeds of sleeves rotation and powers of switching.

The results of the design study of undercarriage of light commercial vehicle are provided in the paper. GAZ 3302 was selected as object of research. Calculations are made using the finite element method and modern software package MSC PATRAN / NASTRAN of license package University MD FEA Bundle. The models of undercarriage with differ- ent types of settings are developed: euro truck, on-board platform, vehicle carrier. The possibility of extension of the frame of the automobile is considered. The developed model includes: frame, cabin, leaf springs, body superstructure. Models loading mode corresponds to the front right wheel display at full weight of the automobile. Picture of strain distribution and maximum equivalent stress by Mises criterion are gained. The calculation of bending stiffness is made. The obtained results of calculations allow to perform a comparative analysis of the original and extended structures with different body superstructures and to evaluate the degree of change in the stiffness and strength of the system. The re- sults of the research say that extension of the automobile frame within 1100 mm is an increase in stress in the average of 10% and a decrease in rigidity by 15%. The values of the maximum stresses remain within acceptable limits. There- fore proposed design of frame has sufficient strength and rigidity in terms of possible operational loads.