he use of vibration transport in agricultural production plays a very significant part. Vibratory conveyors have the variety of advantages over traditional transporting ma-chines such as auger and belt type conveyors used at agri-cultural enterprises for transporting mainly loose and granular materials. A rather low wear coefficient of trans-porting body itself - a conveying trough of a vibration-transporting machine may be referred to the advantages, besides, in some constructions of vibration-transporting machines the amount of friction couples is reduced to a minimum. In the design of constructions of vibration-transporting machines a question arises about the determi-nation of motion mode of particles of the transporting mate-rial. Thus, the detection of a predominant component of motion will allow forecasting the wear rate of a transporting surface and the possibility of enlarging the field of techno-logical use of vibration-transporting machines. During the research process for the determination of motion mode of grain material the shape of which was close to spheroid and ellipsoid, the method of mathematical modeling was applied. The system of differential equations of second order was compiled and solved. In the equations the influ-ence of vibration of a transporting surface on the motion of an elliptically shaped body was taken into account. To solve the system the classical method - Runge-Kutta method of the fourth order was used. The program devel-oped in programming language Python allowed identifying the motion mode of the bodies of spheroidal and ellipsoidal shapes on a vibrating surface. As the result, it was deter-mined that the motion of a body of a spheroidal shape on a vibrating surface was possible due to rolling, and the mo-tion of a body of an ellipsoidal shape was achieved be-cause of its sliding on the surface, what follows from wan-ing rotating movements. The suggested method for the determination of motion mode of a body on a vibrating sur-face is rather flexible and may be applied in calculation for larger bodies in comparison with grain seeds.
Very low wear rate measured in a hip endoprosthesis removed after 38 years