Improved Design and Simulation of an Integrated Ridge-Breaking Earth Cultivator for Ratoon Sugarcane Fields

Ridge-breaking earth cultivation is a new agronomic technology that simplifies and efficiently cultivates ratoon sugarcane. However, traditional cultivators cannot adapt to the distribution of residual stumps, inter-row specifications, and hardened clay soil. This results in substandard soil fragmentation, poor ridge quality, and reduced operational reliability. To address these issues, this article proposes an integrated earth cultivator structure capable of breaking ridges, loosening soil, and raising ridges simultaneously. It is designed to enhance the breaking of tillage layers and the filling of ridges through the coordinated action of multiple soil-engaging components. The effects of pre-loosening by the ridge-breaking plow, high-energy crushing, and throwing by the spirally arranged dense rotary blade group, and soil gathering by the deflector are comprehensively utilized. Additionally, lateral pushing by the ridging plough is employed. Discrete element and finite element simulation results show that densely toothed blades can improve soil supply capacity and structural reliability. This is achieved by increasing the amount of soil throwback and reducing concentrated stress levels. Soil fragmentation rate (<i>SFR</i>) and ridge height (<i>RH</i>) were further used as indicators. Field experiments were conducted to study the effects of operating parameters on breaking and ridging performance. The optimal parameter solution was determined as a forward speed of 0.85 m·s⁻¹ and rotary speed of 289.7 r·min⁻¹. With this adaptive configuration, <i>SFR</i> and <i>RH</i> were improved by 12.4% and 38.5%, respectively, compared with conventional earth cultivators. Additionally, the <i>RSM</i> value of rotary tillage power (<i>P_r</i>) was reduced by 39.6%. Improvements in crushing hardened fields, constructing ridges, and reducing cutting energy consumption have proven effective. This study can provide a reference for the development of earth cultivators based on new agronomy and specific field characteristics.