Bilogurov E. Dynamic methods of diagnosing the vehicle in road conditions

Object of research. Technical state monitoring of vehicles at its dynamic test under road conditions. Target of investigation - improvement of methods for vehicles technical state monitoring at the expense of improvement of dynamic express-methods of diagnosing under road conditions. Subject of investigation. Determination of interrelation between the vehicles and running-out indices and the technical state of the engine and transmission at dynamic test carrying out under road conditions. Theoretical methods of mathematical modeling, analysis of differential equations have been used in the given work. The experimental methods of investigation included full-scale tests of the vehicle under road conditions and laboratory experiments on determination of the moment of inertia of the both wheels and transmission. Scientific novelty of the results detained. The dynamic methods of vehicles technical state estimation found a further implementation. The interrelation between the dynamic indices of the vehicle and the acceleration and running-out time taking into account the technical state of the vehicle has been obtained for the first time. The discrepancy between the theoretical and experimental values of the vehicle motion resistance at different speed modes has been revealed for the first time. On the basis of a big amount of experimental data there were for the first time determined the values of coefficients of air resistance and rolling under road conditions for a great number of motor cars and the character of their change in the range of low speeds that is important for vehicles traction in urban conditions. The practical value of the results detained lies in the fact that there were offered the methods of road control by the driver and checking values of diagnostic parameters "acceleration time" and "running-out" for a number of light vehicles that enables to detect the vehicles technical state disturbance in time as well as to check the results of adjustments, repairs and tuning; the available method of parameters control values calculation is grounded and the grounded in the work specifications of mathematical models of motion resistance and the detained values of resistance coefficients can be applied at calculation of functional indicies of motor cars at the stage of designing. The mathematical models of calculation of vehicle traction dynamics equasion constituents at undermined modes of vehicle motion and calculation of control values of diagnostic parameter (acceleration and running-out time) for vehicle technical state monitorihg are implemented and used at scientific - production enterprise "Karsis", the developed dynamic express - method of diagnosing and applied at the service station "Mobilservis". Field of application: automobile enterprises, system of technical service of automobile transport.