Parameter optimization and numerical analysis of the double disc digging shovel for corn root-soil complex

Under conservation tillage conditions, the presence of corn stubble has become the main obstacle affecting no-till planting. To address this issue, we propose a method of digging followed by processing. A double disc digging shovel (D-D-S) is designed while minimizing soil disturbance. By constructing a kinematic model, the mathematical relationship between its motion characteristics and key parameters is revealed. Furthermore, in-depth analysis is conducted on the mechanical behavior of D-D-S, and corresponding mechanical model is established based on this. The results of the parameter optimization tests show that when the horizontal deflection angle of the discs is 31°, the vertical deflection angle is 27°, and the spacing is 0.5 cm, the relative errors of forward displacement of the corn root-soil complex (CRSC), longitudinal displacement of CRSC, soil disturbance area, and draught force compared to the predicted values are 8.2 %, 9.3 %, 9.6 %, and 6.8 %, respectively. The movement of particles during the digging and throwing process of the D-D-S is analyzed using DEM. The D-D-S can not only dig the CRSC and lift it to an appropriate height but also backfill a certain amount of the digging soil. Comparisons between simulation test and validation test show that the soil disturbance area of both methods differ by only 7.84 %. The relative errors of the forward and longitudinal displacements of the CRSC are 8.52 % and 4.05 %, respectively, and the verification test and simulation results are basically consistent. The developed D-D-S is of significant importance for the treatment of corn stubble under conservation tillage conditions.