To enhance the operational stability and adaptability of soil-covering and compaction devices during no-till seeding on sloped farmland, this study developed a DEM–MBD coupled simulation model suited for conditions involving real-time slope variation and applied it to the design and analysis of a slope-adaptive covering–compacting device (SACCD). By coupling multi-body dynamics with the discrete element method, the model simulated the motion behavior and soil interaction process of the SACCD under different slope change rates, revealing its asynchronous response characteristics and profiling compaction mechanisms during dynamic slope transitions. Field experiments further verified the device’s performance and the accuracy of the simulation. At the Lishu test site, the SACCD achieved a coefficient of variation of soil compaction of 20.4% under an average surface slope variation rate of 0.087 rad/s. At the Keshan test site, the coefficient of variation of soil compaction was 18.9%, with an almost constant slope. The differences between simulation and field results for the coefficient of variation of soil compaction were 8.32% (Lishu) and 1.02% (Keshan), confirming the reliability of the model and the rationality of the SACCD structural design. Overall, the simulation and field results demonstrate that the SACCD can maintain effective profiling posture and compaction performance under dynamic slope variation, providing a feasible approach and theoretical basis for the design and performance prediction of soil-covering and compaction devices for complex sloped farmland.

To solve the problem of field waterlogging during wheat sowing in rice-wheat rotation areas, which causes sticky and wet soil, thus affecting the growth of wheat, this paper proposed a sloped ditching method based on laser alignment technology, and designed a combined ditching device with a front ditching shovel (FDS) and a rear ditching plow (RDP) to create sloped drainage furrows when sowing wheat. The key factors affecting the performance of RDP and value ranges were determined through theoretical analysis. Through discrete element method (DEM) simulation, the influence of different structural parameter combinations on slope stability was studied, and the optimal parameter combination was determined as the soil lifting angle of 50°, the minimum element angle of 35°, and the maximum element angle of 40°. The field test showed that the ditching device can effectively create sloped trapezoidal drainage furrows. The slope stability coefficient and slope accuracy coefficient were both greater than 85%, which meets the requirements of drainage. This paper provides a new ditching method and theoretical basis for the development of a sowing and ditching combined machine in rice stubble fields.