According to the agronomic requirements of cotton precision seeding, the researchers designed a split seeding system to achieve high-speed precision seeding on the membrane. The 3D models used in the simulation process were created using Solidworks. They used the built-in Flow Simulation plug-in in SolidWorks to simulate the flow field in the drum and to grasp the air velocity and pressure changes. The CFD-DEM (computational fluid dynamics and discrete element method) coupling method was used to simulate the positive pressure airflow to transport the seeds, so as to grasp the movement of the seeds in the seed tube. EDEM (engineering discrete element modeling) was used to simulate the seeding process of the hole seeder, to understand the movement speed and trajectory of the seeds inside the hole seeder, and to analyze the reasons for missed seeding and reseeding. A three-factor, five-stage quadratic rotation orthogonal combination test was designed using Design-expert 13.0 software. This test evaluates the performance of a split seeding system by establishing a response surface for the seed rate, using the hole seeder speed, negative pressure, and hole diameter as test factors. The optimal parameter combination is obtained by optimizing the regression equation, which is further verified by bench tests. Under the hole seeding speed of 47.98 r/min, the negative pressure of 1.96 kPa and the hole diameter of 3.5 mm, the precision seeding system achieved a single seed rate of 90.9% and a missed seed rate of 4.3%. The verification test results are consistent with the optimization results, which meet the agronomic requirements of high-speed precision film seeding. This research provides a better technical solution for the application development of a precision seeder.

In order to solve the problems of poor stability of the output speed and poor synchronization of the pump-controlled dual motor in a hydraulic travel system during step input speed and external load disturbance, different control strategies were designed and compared with the state machine using the statechart module control, Z-N frequency response PID control, and GA-based PID parameter self-tuning methods. Our analysis shows that the BP algorithm-based PID parameter self-tuning control method has no overshoot and that the three methods reduced the target speed tracking time by 90.11%, 75.12% and 36.55%, respectively. The average synchronous error for the system output speed was 7.95%. The stability and synchronization requirements of the constant speed of the hydraulic travel system were satisfied. These research results can provide a reference for the design and application of constant speed control for pump-controlled dual-motor hydraulic travel systems in the fields of engineering and agricultural machinery.

In order to study the working mechanism and sowing effect of seed delivery pipes and their associated cavity seeders, the factors affecting the sowing test were first derived through pressure loss theory and force analysis of cotton seed particles in the gas-solid coupling field. Secondly, Ansys fluent was used to simulate the flow field of seed delivery pipe joints to study the effect of seed delivery pipe joints on the overall pressure loss and uniformity of air pressure distribution and to determine the optimal structure of seed delivery pipe joints. Then, the EDEM was simulated for the overall seed delivery pipe and its associated cavity seeders in the absence of positive pressure to analyze the transport pattern of each cotton seed. Finally, CFD-DEM gas-solid coupling simulation experiments were conducted on the center of two rows of seed delivery pipes and their connected cavity seeders to analyze the trajectory of cotton seeds under different rotational speeds of cavity seeders and different positive seed delivery pressures and to deeply analyze the causes of Multiple seeding and Miss-seeding. At the same time, the seeding performance was evaluated by coupling simulation values with single seeding rate and multiple seeding rate as seeding performance evaluation indexes and compared with bench test. The results show that in the coupling simulation, when the speed of the cavity seeders is 20~40 rev/min and the seed delivery tube is passed into 50~150 Pa positive pressure airflow, the single seeding rate is not less than 83.06%, and the missed seeding rate is not more than 9.23%. In the bench test, the single seeding rate was not less than 80.64%, and the missed seeding rate was not more than 9.86% under the same cavity seeders speed and positive pressure, and the results of the bench test and the simulation test were close and consistent, which verified the feasibility of the simulation.

This paper addresses the hole-forming process of a duckbilled hole-forming device. Based on a coupled simulation using the multi-body dynamics software RecurDyn and the discrete element software EDEM, the hole-forming mechanism of a duckbilled hole-forming device and the influence of control parameters on the hole-forming performance of the hole-forming device were studied. In this paper, we analyze the direction and speed of soil particles transported under soil disturbance by a hole-forming device through the simulation and study of the hole-forming mechanism of the hole-forming device. By controlling parameters such as the traction angle, forward speed, and mass of the hole-forming device, the influence of the control parameters on the hole-forming trajectory of the duckbilled hole-forming device was investigated. Orthogonal tests determined the optimal combination of control parameters. The results show that the hole-forming process of the hole-forming device mainly comprises squeezing and shearing the soil to form holes, and the hole-forming performance of the hole-forming device was optimal when the traction angle was 17.3°, the forward speed was 1.11 m/s, and the mass of the hole-forming device was 17.9 kg.

This study is based on the influence of power shift control on the smoothness of cotton picker shifts and proposes an optimization method for the smoothness of power shifts with different control strategies for the gearbox. Through the structural design of the power shift mechanism control module, the hydraulic power distribution of the hydraulic system of the hydraulic travel module and its control mode are analyzed, and a regional cooperative shift control strategy is proposed in conjunction with control theory. A model of cotton picker dynamics was built using AMESim simulation software. In addition, the traditional control strategy was simulated and compared with the Statement component automatic control strategy to analyze and discuss the control deficiencies in power shift smoothness. Then, a particle swarm genetic algorithm (PSGA) was constructed by integrating the PSO algorithm and the genetic algorithm to verify the effectiveness of the algorithm in improving the dynamic performance and shift smoothness of the gearbox. The algorithm was verified using bench tests, and the algorithm improved the harvesting quality and efficiency of the cotton picker.

In response to the issues of slow dynamic response, uneven shifting, and strong jolting during the starting and shifting operations of the cotton picker, we established a model for automatic power shifting control. We proposed optimization strategies using the Statechart logic control method and BP neural network control method. Different control effects were analyzed concerning pressure, flow rate, motor speed, vehicle speed, impact degree, and slip-grinding work. The results showed that the Statechart logic control method increased the response time of the flow rate by 46.67% during the starting process, with a good linear characteristic during the variation. It reduced the impact during starting and shifting by 38.57% and 67%, and the sliding friction power during starting and shifting by 51.95% and 33.33% respectively. The BP neural network control method reduced the pressure overshoot during starting and shifting by 25% and 30.77%, respectively, demonstrating better robustness. The pump, motor speed, and vehicle speed showed smooth growth after starting and shifting, with faster vehicle speed response during the starting process. Additionally, the vehicle speed overshoot during shifting significantly decreased, ensuring overall performance that meets the operational requirements of the cotton picker. This finding holds practical significance for the advancement of control strategy optimization and the development of the control system for the powershift gearbox in cotton pickers.