To address problems encountered in current potato harvesting machines in hilly and mountainous areas, such as potato damage, poor adaptability, low operational efficiency, and the inability of traditional harvesters to meet the requirements in these areas, a new potato harvester equipped with excavation and a multi-stage separation conveyor was developed by using design and simulation programs as an innovative way to identify the best operating factors. SolidWorks Software was used to design an excavation and a multi-stage separation conveyor. ANSYS Workbench machine static structure analyzed stress, strain, and deformation. The working process of soil and tuber separation was tested and kinematically analyzed by EDEM-RecurDyn and a 5F01M camera. A field experiment was also conducted on the machine under several factors: working speed (W), excavation depth (D), vibration intensity level (V), and conveyor inclination angle (N). The quadratic regression orthogonal rotating combination experiment tested four factors with five levels. The results of the non-load experiment showed that the lowest ratio of impurities was at the linear speed level (Q3, S5, O3) for the first and second separation conveyor and the side conveyor, respectively. The results of the field experiment showed that the optimal parameters were the working speed of 1.05 m/s, the digging depth of 180 mm, and the vibration force II inclination angle on the screen surface of 22 degrees, which gave the highest potato lifting rate of 98.8%, and the bruising rate was 1.37%. The damage rate was 1.43%, superior to national industry standards. With its exceptional performance, the machine can effectively meet and solve the challenges of harvesting requirements, making it a valuable tool for the industry.

The limited separation efficiency of potato-soil separation equipment in the southern potato planting areas is attributed to the high viscosity of the soil. To enhance the performance of the lifting chain separation device, a concave bar was designed. Structural parameters influencing the efficiency of potato-soil separation by bars were determined through kinetic analysis during the separation and transportation of potato-soil mixtures. Both a potato simulation model and a sticky soil simulation model were developed. Simulation tests indicated that the concave bar outperforms the straight bar in separation efficiency. Key factors investigated include the angle of the concave side, the width of the concave bar, the depth of the concave bar, and the installation angle. Orthogonal simulations were conducted using separation efficiency and the maximum force on potatoes as evaluation metrics. The results demonstrated that with a concave side angle of 15 degrees, a concave bar width of 450 mm, a concave bar depth of 60 mm, and an installation angle of 30 degrees, the separation efficiency of the potato-soil mixture reached 79.7%, with a maximum force on potatoes of 35.218 N, achieving the highest separation efficiency. Based on these results, test devices were constructed, and field tests were performed. The field test results showed a damage rate of 1.58%, a potato epidermal injury rate of 1.03%, and a loss rate of 2.87%. These results comply with national standards and validate the reliability of the simulation findings.

At present, the potato's mechanized harvesting rate in hilly and mountainous areas is very low. The reasons for this are that in heavy soil, the separation of potato rhizomes from soil or vines is not sufficient, harvesting machinery is seriously damaged by the potato epidermis, and the harvested potato is easily buried in soil, resulting in a missed harvest. In this paper, a two-stage cleaning potato harvester with wave-type and roller-group-type separating mechanisms was designed, and its overall structure and working principle are introduced in detail. The new cleaning mechanism can increase the effective separating length and effective contact area of the potato-soil mixture so as to achieve the purpose of removing clay and heavy soil. The main separator uses a structure that combines offset waves with opposite waves and a staggered arrangement of large-small diameter straight bars. The secondary separator adopts a device combining left-hand and right-hand separating rollers. The discrete element model of the whole machine was established, and the results of the theoretical analysis were verified by simulation. The key factors affecting the harvest quality were analyzed by variance analysis and response surface analysis, and the field experiment was carried out with the rate of clean potatoes, damaged potatoes, and peeled potatoes harvested as the indexes. The field experiments showed that the machine achieved a rate of photos on or out of the earth of 98.87%, a damaged potato rate of 0.91%, and a peeled potato rate of 1.13%. The research results provide theoretical support and a technical reference for the design and optimization of potato harvesters, as well as the improvement of the potato-soil separating efficiency and harvest quality.