Automatic rigidity adjuster sustaining tillage depth during the work of cultivators with elastic rods

Abstract

This paper presents the benefits and disadvantages of the elastic cultivator rags usage. The analysis of the bending moment alongside the rod was made. Shear and moment diagrams were designed to describe the horizontal and vertical forces applying on the cultivator foot. While the resistive force is increasing, the tillage depth is decreasing as a result of a rack deformation. The analyzes of scientific papers on tillage depth stabilizing shows that Euler’s equation is the basis for the subsequent calculations. However, this equation defines the sustainability of longitudinally bend compressed rods in mechanics. Thus, the Euler’s equation has limitations and could not be used in full to solve the deformation problem. While studying curved rods movement using Mohr’s integral, the optimal position of the rigidity adjuster was found. The minimizing of the foot instability and excess movement could be done by the change of the rod length and decrease of the bending moment. In order to maintain the constant tillage depth, the rigidity adjuster was installed. The flexible tubes were used as a controller. The change in hydraulic pressure causes the shift of the impact forces applied on the rod and, as a result, the total bending moment decreases. The described above transformations make the method quite comprehensive. The analysis of the force impact deviation depending on the adjuster position is shown in the paper. That evaluations were used in further calculations, and the optimal position of the rigidity controller on the rod was found. The preliminary assessment allowed to conclude that the evenness of the tillage depth depends on the hydraulic pressure and resistive soil force could be compensated.