Aiming at the problems of poor passability of a tracked chassis due to small plots, complicated road conditions and steep slopes during mechanized potato harvesting in hilly and mountainous areas. To design a potato combine harvester and take the tracked chassis of the harvester as the research object to study its driving performance under typical road conditions in mountainous areas. Firstly, mechanical analysis and theoretical calculation are carried out on the tracked chassis to obtain the relevant parameters of key components, and secondly, its driving performance is analyzed to obtain the driving limit values of passing performance under different working conditions; RecurDyn software was used to establish the dynamics simulation and analysis model of the whole machine, and the driving limit values of the harvester were determined under five different road conditions through simulation. The results show the following: the driving limit gradient angle is 20° in cross-gradient conditions, 25° in longitudinal up-gradient conditions, 25° in longitudinal down-gradient conditions, the limiting height of the chassis that can be overpassed in obstacle-crossing conditions is 450 mm, and the limiting width of the chassis that can be spanned in trench-crossing conditions is 1200 mm. The simulation results were verified through field tests, and the results of the field tests showed that the harvester met the requirements of stable travelling on longitudinal slopes of 24°, climbed over a 450 mm straight wall and crossed over a 1200 mm trench, which were similar to the simulation results, indicating that the simulation results were accurate and feasible, and met the design requirements for the travelling passage of the crawler potato harvester. This study provides an in-depth understanding of the tracked chassis of the potato combine harvester in hilly mountainous areas, with a view to providing reference for the design of tracked harvesters for other crops in hilly mountainous areas.

To address the issues of the poor filling and clearing efficiency of spoon–chain potato seed dischargers, an optimization design was implemented in this study. Based on the motion characteristics of potatoes during the filling and transport processes, an inclination angle was set for the seed spoon cavity, and a seed-clearing brush was installed at the top of the seed discharger. A DEM-MBD coupled simulation model of the seed discharger was constructed. The working speed of the driving sprocket, the inclination angle of the seed spoon cavity, and the seed holding height were used as experimental factors, while the single-seed qualification rate, missed seed rate, and over-seeding rate were used as evaluation indices to conduct a quadratic regression orthogonal rotation combination experiment. This determined the optimal technical parameter combination for the best working performance. Based on the results of the DEM-MBD coupled simulation experiments, a response surface optimization test was conducted. The results showed that the optimal working performance was achieved when the working speed of the driving sprocket was 43 rpm, the inclination angle of the seed spoon cavity was 15°, and the seed holding height was 0.2 m. Under these conditions, the single-seed qualification rate was 95.28%, the missed seed rate was 0.92%, and the over-seeding rate was 3.80%. Further soil bin tests confirmed that, under the optimal working parameters, the relative deviations of all test indices from the response surface optimization test results were less than 2%. The research results provide new insights for the optimization design of spoon–chain potato seed-metering devices.

Plastic film mulching technology can effectively enhance crop yield and quality, and the use of mulch has been increasing in recent years; however, the problem of mulch residue is worsening due to the large amount of recycling work and slow natural degradation. In this study, a potato seedling killing and residual film recycling machine is designed to provide good working conditions for potato harvesters before harvesting in response to the problems of difficult separation of film tangles, the low net rate of recycling due to the mixing of residual film with soil, and the high soil content in residual film recycling operations in northwest China. The machine is based on the potato monoculture and double row planting mode in Gansu area. This paper puts forward the overall design scheme and carries out the theoretical analysis and parameter determination of the key components, such as the seedling killing device, the film surface cleaning device, the film unloading device, and so on. Using EDEM software to carry out the virtual simulation test and Design-Expert13 to analyze the test results, we determined the optimal working scheme for the machine, with a forward speed of 0.8 m/s, a film gap of 125 mm, and a spiral stirrer speed of 600 r/min. Based on a field test for verification, the test results show that the machine’s residual film recovery rate was 83.3%, the impurity rate was 3.8%, and the rate of injury to the potatoes was 1.4%. The machine meets the requirements of national and industry standards, and it can simultaneously realize straw crushing, film surface cleaning, residual film recycling, and hydraulic film unloading operations, with better operating results and while reaching the expected results. It can also provide a reference for the design and testing of a seeding and residual film recycling machine.

Aiming at the problems of low soil cover and serious wear and tear of transmission parts in the soil lifting device of potato planters, this paper carries out innovative optimization design of its key parts based on TRIZ theory. The discrete element model of the soil model and the multi-body dynamic model of the soil lifting device are established, the upper scraping and lower scraping soil lifting devices are simulated respectively through the method of DEM-MBD coupling, and the working mechanism of the soil lifting device is further explored. The simulation results show that the lower scraping type lifting device has a large conveying capacity and a stable flow rate at the soil outlet. The results of the soil tank performance comparison test show that: the improved soil lifting device has a simple structure, large conveying capacity, stable flow rate, and fast flow speed and is not easily congested. It meets the standard requirements of dryland potato seedling strip mulching planting technology on mulching parameters and is of great significance for improving dryland food production on the Loess Plateau.