**6. Discussion**

From the test results, it can be obtained that the average success rate of pulling of low-loss harvesting test platform was 92.7%, the average success rate of clamping and conveying was 88.6%, the average success rate of root cutting was 89.3%, the average qualified rate of harvesting in the pulling link was 86.7%, the average qualified rate of harvesting in the clamping and conveying link was 75.3%, and the average qualified rate of harvesting in the cutting link was 77.3%. The average damage rate of the pulling process was 7.32%, the average damage rate of the clamping and conveying link was 12%, and the average damage rate of the cutting process was 11.34%. During the test, the orderly feeding of cabbage can be realized by controlling the working frequency of the servo motor of the conveying system to avoid blockage and failure of operation performance. The pulling device and the reeling device can successfully pull the cabbage from the conveying bench, straighten up the cabbage to the feeding inlet of the clamping conveying device, and complete an effective harvest with the cutting device. Therefore, the test platform meets the technical requirements for the harvest of cabbage.

According to the test results, it can be inferred that when the pulling device is controlled at 80–120 r/min, the speed of the clamping and conveying device is controlled at 120–240 r/min, and the speed of the double disc cutter is controlled at 140–180 r/min, each link of the harvesting system has a high success rate. By observing the results of the aggregate box of each link, it can be seen that the damage rate of the pulling link in the harvesting system is low, while the damage rate of the clamping, conveying, and cutting links is high. Figure 16 shows the harvesting process and damage types of the low-loss harvesting test platform for cabbage. The reasons for the above phenomena are as follows: (1) The cabbage is not straightened when entering the clamping conveyor belt feeding inlet through the pulling device, which causes the root cutting position to shift. (2) The friction coefficient of the conveyor belt material is large, and the cabbage is scratched during the clamping and conveying process. (3) The too-fast or too-slow speed of the clamping conveyor belt makes the time of the cutter acting on the rhizome shorter in unit time, and the rhizome is not cut off or slipped. From the above causes of damage, it can be determined that the taper of the pulling roller, the material of the clamping conveyor belt, and the ratio of the clamping conveyor belt to the cutter head motion parameters are the key factors affecting the qualified rate of harvesting. Therefore, the experimental optimization will be carried out in the follow-up study in order to find out the critical conditions, the best equipment material, and the optimal working parameter combination for the damage of the cabbage in each link of the harvesting system and provide data support for the low-loss harvesting equipment for the cabbage.
