With the extensive use of plastic film mulching in planting, the amount of residual plastic film in soil has been increasing, causing soil and water pollution, harming crop growth, and reducing agricultural product quality and yield. In response to this issue, this study proposes a roll-type residual film recovery mechanism using the tillage layer method. The structure and operation principles of this system are discussed, and a detailed analysis of its key components and working process is provided. The lifting cutter operates at a speed of 22.37 rad/s, the pick-up drum at 4.58 rad/s, the roll forward rotation picks up the film at 13.74 rad/s, and the roll reverse film rotation unloads the film at 17.57 rad/s, with the unloading wheel rotating at a speed of 4.5 rad/s. ADAMS (software of automatic dynamic analysis of mechanical systems) Version No.2019 is used for modeling and analysis, and the displacement and velocity change patterns of MARKER_499, MARKER_500, and MARKER_505, which are marked points of the spring-tooth tips and are found to be the same. The maximum resultant displacement of MARKER_499 and MARKER_500 is 22.146 mm when picking up plastic film and 17.047 mm when unloading plastic film. Meanwhile, the maximum resultant displacement of MARKER_500 and MARKER_505 is 231.715 mm in the film-picking area and 234.028 mm in the film-unloading area. After analyzing the velocity of MARKER_499 during picking and unloading of the film, it was determined that the absolute velocity for the picking direction was 79,809.407 mm/s, and for the unloading direction it was 10,2266.168 mm/s. Bench tests show a tillage gathering rate of 71.6% and a surface gathering rate of 83.4%, meeting the performance requirements of the roller-type residual film recovery mechanism. These findings provide a theoretical basis for the design of the structure and operational parameters for the roll-type residual film recovery mechanism using the tillage layer method.

The working principle and key components of a chain drive residual film recovery machine were studied. A kinematic analysis of the chain drive soil separation mechanism was completed by applying ADAMS software to obtain the trajectory, displacement, velocity and acceleration of the center of mass of the chain plate link_1 in the x- and y-directions within the effective shaking displacement. A field test of the chain drive separation mechanism was carried out. When the shaking roller was in contact with the chain, the change in speed of the chain in the x- and y-directions was not significant, but the force in the y-direction was conducive to breaking the soil pieces and improving the rate of collecting the residual film. The change in the speed of link_1 in the y-direction speed with x-direction speed explained the action of the separation mechanism on conveying and throwing of the film-soil mixture in the horizontal and vertical directions, which revealed the mechanism of the chain drive film-soil separation equipment. The field test showed that the film collection rate of the chain drive separation mechanism was 68%, and the surface residue was 6%. The test results meet the relevant national and industry standards and design requirements. The results of this study provide guidance for the design and optimization of chain drive film-soil separation equipment.

The geometric characteristics, physical parameters and contact parameters of coated cotton seeds were obtained through theoretical analysis and experimental measurements. A discrete element model reflecting the intrinsic parameters of cotton seeds was established, the contact parameters of coated cotton seeds were calibrated using Discrete Element Method (DEM), and the significant factors affecting the stacking angle were screened using the Plackett-Burman method. The optimal ranges of the parameters were determined by the steepest ascent method, and a second-order regression model of the stacking angle and significant parameters was established by a central composite design. The following optimal values were obtained for cotton seeds: collision recovery (0.38), static friction (0.57) and rolling friction (0.19) coefficients. The average value of the stacking angle obtained by simulations with the best combination of parameters was 30.52°, the result of the simulation test was 30.91°, and the relative error was 1.278%. It is shown that the discrete element particle model and calibration parameters of cotton seed are closer to the actual situation, which can provide theoretical reference for analyzing the precise seeding of cotton seed and optimizing the structural parameters of seed disperser.

The extended duration of mulching in Xinjiang cotton fields leads to a significant decline in the tensile strength of plastic film. When recycling is in operation, the soil and the spring teeth of the machinery used can easily cause secondary damage and fracture the residual film. Establishing appropriate working parameters for recycling is essential to enhance the overall quality of collection efforts. By analyzing the motion process of a chain-tooth residual film pickup device, we identified key working parameters that significantly impact the efficiency of recycling. Employing the finite element method (FEM) and a coupled algorithm incorporating smooth particle hydrodynamics (SPH), we developed a coupled finite element model representing the interaction among spring teeth, soil, and residual film. Through simulation and analysis of the process of inserting the spring teeth into the soil to collect film, we derived the governing rules for residual film stress and deformation changes. Utilizing forward speed, rotational angular velocity, and angle of entry into the soil of the spring teeth as test factors and selecting the residual film stress and the residual film deformation as test indices, we conducted a multi-factor simulation test. We established a mathematical model correlating test factors with test indices, and the influence of each factor on the test index was analyzed. Subsequently, we optimized the working parameters of the spring teeth. The results indicated that the optimal working parameters are forward speed of 1111.11 mm/s, rotational angular velocity of 25 rad/s, and angle of entry into the soil of 30°. At these values, the average peak stress of residual film was 4.51 MPa and the height of residual film pickup was 84.48 mm. To validate the optimized the spring teeth impact on performance, field experiments were conducted with recovery rate and winding rate as test indices. The results demonstrated a 92.1% recovery rate and a 1.1% winding rate under the optimal combination of working parameters. The finite element model presented in this paper serves as a reference for designing and analyzing key components of residual film recycling machines.

Seeding depth is a critical factor influencing the uniformity and vigor of wheat seedlings. To address inconsistent seeding depth in wide-row uniform seeding agricultural practices, we performed parameter analysis and optimization experiments on the seeding depth device of a wheat wide-row uniform seeding machine. The structure and working principle of the device were described, soil movement during operation was analyzed, and the models of rotary tiller blades and soil retention plates were investigated, identifying three key factors affecting seeding quality. Using the discrete element method, a model of the seeding depth device was established, and experiments were conducted, yielding the following conclusions: 1. Single-factor experiments were conducted under different seeding rate conditions, and it was found that the effects of various factors on the two indicators, namely the seeding depth qualification rate and the coefficient of variation for seeding uniformity, were regular. 2. A quadratic orthogonal rotated combination experiment with three factors determined the optimal structural parameters: tillage device penetration depth of 120 mm, rotational speed of 310 rpm, and soil retention plate inclination angle of 27°. Under these parameters, the seed depth qualification rate exceeded 90%, and the coefficient of variation for seed distribution uniformity was below 25%. 3. Field validation tests under optimal parameters confirmed a seed depth qualification rate ≥90% and variation for seed distribution uniformity was below ≤20.69%. 4. The error between simulation and field tests was ≤5%, validating the reliability of the discrete element method-based optimization for the seeding depth device.

To address the restricted operating space in reserved maize sowing strips, surface soil compaction, the poor trafficability of conventional tillage machinery, and the risk of disturbing adjacent wheat rows under wheat–maize relay intercropping in Xinjiang, a front-mounted narrow-strip tillage device for a maize interseeder was designed. The device comprises a rotary tillage assembly and a soil-lifting device. An IT225 rotary blade was selected, and the structures of the rotary tillage assembly and the pointed-shovel soil-lifting device were designed. Kinematic and force analyses established operating ranges of 3–5 km·h⁻¹ for forward speed, 240–360 r·min⁻¹ for blade-shaft rotational speed, and 80–120 mm for rotary tillage depth. A discrete element model of the soil–tillage device interaction was developed in EDEM. A three-factor, three-level Box–Behnken experiment was conducted with forward speed, blade-shaft rotational speed, and rotary tillage depth as factors and soil fragmentation rate and soil bulk density as responses. Quadratic regression models were developed using Design-Expert and subjected to constrained numerical optimization. Both regression models were highly significant, whereas their lack-of-fit terms were nonsignificant, indicating good predictive performance. The optimum combination comprised a forward speed of 3.88 km·h⁻¹, a blade-shaft rotational speed of 348 r·min⁻¹, and a rotary tillage depth of 120 mm; the corresponding predicted soil fragmentation rate and soil bulk density were 92.40% and 1.38 g·cm⁻³, respectively. Field validation produced a soil fragmentation rate of 93.64% and a soil bulk density of 1.35 g·cm⁻³; the corresponding relative errors were 1.34% and 2.17%, respectively, both below 5%. These findings provide a basis for the design and operating-parameter matching of tillage components for maize interseeders used in wheat–maize relay intercropping in Xinjiang.