Curvilinear Movement of a Four-Wheel Machine Using a Satellite Navigation System

Abstract

Tractors when performing agricultural and transport work move in a straight or curved trajectory, the curvature of which is constantly changing. Compilation of equations of curvilinear motion is one of the main tasks of modeling the turning. Fundamentally different assumptions underlying the description of the force interaction of the wheeled and tracked propulsion with the soil, led to the formation of different methodological approaches in the study of curvilinear motion of machines. Many of them have tried to obtain the equation of the trajectory by analytical, graphical and graph-analytical methods. This uses both approximate methods and accurate mathematical models that are too complex to use in practice. The necessity of studying the trajectories of unsteady motion is substantiated in the article. Full automation of control of work of machines and machine-tractor units without participation of the driver needs to provide receiving the exact information on position of the unit concerning the set trajectory during all time of work. The aim of the study is to experimentally confirm the theoretical universal equations in parametric form for a given trajectory of curvilinear motion of a four-wheeled machine with controlled front wheels for sections of entrance to turn and exit of turn depending on the swing angle of the frame car taking into account the intensity of turning. In this article, the analytical equations confirm the curved path of a four-wheeled vehicle with front steered wheels by using parametric equations depending on the swing angle of the frame car φ. Based on analytical equations for a given trajectory of curvilinear motion in parametric form for the car, experimental trajectories were obtained taking into account the intensity of turning the front wheels or car steering wheel to enter the turn and exit the turn of both directions (left and right) car Renault Logan using satellite navigation system. The results of the article can be used in the future to plan MTU reversals, which should be made the most rational and economical, when performing agricultural work, to limit unproductive power consumption and prevent damage to land on which reversals are performed, or to automatically for automatic control of units and machines.