Aiming at the problem that the existing seed potato cutting machine often cuts the top bud of the potato, a clamping method of seed potato was adopted to cut the potato, and a clamping device was designed to effectively retain the top advantage of seed potato. The device includes clamping claws, supporting plates, and a spring seat. A threefactor and threelevel orthogonal test was conducted, with feeding height, spring stiffness coefficient, and splint material as test factors and empty bowl rate and loss rate as evaluation indicators. The test results were analyzed by range, and the optimal parameter combination was determined. The verification test results showed that when the feeding height was 100 mm, the spring stiffness coefficient was 60 N/m, and the splint material was EVA, the empty bowl rate was 2.68%, and the loss rate was 4.43%. Under this parameter combination, the miss rate and loss rate were both low, meeting the potato cutting requirements.

In order to reduce the potatoes drop damage in the process of sorting and explore the separator working conditions than can influence the potato drop damage, this paper took 'Helan15' as the experimental material, using the conveying speed, excluding force, the drop height and the moisture content of potato separator as the test factors, and potato drop damage level as the response value, Quadratic regression orthogonal rotation test was carried out. The malformed variance analysis of the test results was conducted by Design-Expert 8.0.6 software. The influence of each experimental factor on the damage level of potato drop was explored by response surface, and the optimal working parameters of potato sorter were determined. The results of the drop test showed that the order of the degree of influence on the damage level of potato drop was water content, drop height, conveying speed, and removal force. When the conveying speed was 0.3 m/s, the removing force was 15 N, the falling height was 45 cm, and the water content was 75.36%, the sorting machine had the lowest drop damage grade on potatoes. The actual drop damage grade of potatoes was 0.84, which fitted well with the predicted value.