Coupling Characteristics of Potato Ridging and Profiling-Type Shaping Operations Under Hilly-Mountainous Terrain Conditions

Owing to uneven ground conditions in hilly-mountainous regions, a profiling-type shaping mechanism was adopted to follow terrain fluctuations and simultaneously complete ridge shaping. The influencing factors of ridging and profiling-type shaping were investigated, and their coupling relationship was analyzed. An EDEM–RecurDyn coupled discrete element–multibody dynamics model was established to investigate soil particle motion and ridge formation. Single-factor tests and a three-factor, three-level Box–Behnken response surface experiment were conducted using the horizontal inclination angle of the soil-covering plate, ridging blade installation angle, and blade rotational speed as factors, with the qualification rates of ridge dimensions and soil compaction as evaluation indices. As the factor levels increased, both indices initially increased and then decreased. The ridging blade installation angle had the greatest effect on ridge dimensions, whereas the soil-covering plate angle had the greatest effect on soil compaction. After rounding the multi-objective optimization results to match the practical adjustment precision of the machine, the optimal parameters were determined as a soil-covering plate angle of 25°, a ridging blade installation angle of 30°, and a rotational speed of 410 r/min. Under these conditions, the predicted qualification rates of ridge dimensions and soil compaction were 91.37% and 95.34%, respectively. Field tests using the optimal parameter combination yielded corresponding qualification rates of 88.6% and 91.4%, with relative errors of 3.0% and 4.1% compared with the predicted values. The results provide a basis for coordinated matching between soil supply and shaping compaction during potato ridging in hilly heavy clay soils.