Pulsed Nonlinear Automatic Control System for Guidance of a Caterpillar Tractor Unit in Vineyards

Abstract

The automatic guidance systems of tractors for soil cultivation in vineyards have attracted the attention of researchers since the second half of the twentieth century. The purpose of this paper is to investigate the driving quality of an automatic guidance system (AGS) for a caterpillar tractor unit (CTU) consisting of a crawler tractor and a vineyard plow and having the orientation system by grapes stamps. Compared with the known works (in which GPS, LIDAR, and video cameras are used for orientation), the proposed system is the least expensive. For this, the existence of stability of the AGS as a whole in the range of operating speeds of the unit was proved. The dynamic model of the vineyard plow was verified on a three-point hitching system of the tractor, field tests of the AGS were carried out, which confirmed the results of theoretical studies, and suggested directions for further research. The shape and parameters of the modulation characteristic (MC) of the pulse-width modulator (PWM) of the AGS control system, the rational values of the hydraulic drive speeds of the sequential control mechanism of the clutch of the turn and the crawler tractor belt brake, were established, depending on the slope angle and the speed of the unit, ensuring agrotechnical requirements for driving. New solutions, in comparison with the known ones, are the ways of forming the MC of PWM using a new design probe and the associated driver MC of PWM.

Keywords

• automatic guidance
• a
• caterpillar tractor