Mathematical design of motion of the joined wheeled machine without resilient element in connecting hinge

Abstract

As a result of undertaken theoretical studies, the mathematical model of motion on unevenness of surface of the articulated wheeled machine sections is got. At drafting of dynamic model of motion on unevenness of surface of the articulated wheeled machine the basic structural parameters, that influence on firmness of his position inplane, perpendicular to the underlayment, as well as the characteristics of supporting surface, were taken into account. The proposed approach allows to take into account vertical and angular vibrations of the sprung and the unsprung masses; visco-elastic characteristics of the tractor suspension and tires. For the construction of equalizations of tractor sections motion the Lagrange equalization is used, coming from the structural features of the articulated wheeled tractor, the row of suppositions is accepted for simplification of mathematical model. In the considered variant a connecting hinge of tractor is a standard construction without an elastic element. Thus, ignoring a friction in a horizontal hinge, it is accepted, that the sections of tractor move in a vertical transversal plane independently one from other. The change in the inclination angles of the forming surface irregularities under the wheels of the articulated tractor sections is given in the form of periodic functions. As a parameter of dynamic stability of position the angular speeds of sections are considered in a transversal plane perpendicular to the underlayment.
Calculations are conducted on the example of the articulated wheeled tractor with nominal traction force of 35 kN with corresponding characteristics with the use of numeral decision using PC (numeral Runge-Kutta method with time step correction). Error in determination of high angular speeds of sections in a vertical transversal plane with the use of mathematical design, as compared to experimental data, was not more than 10%.