Abstract:Comparison research was carried out on the performance of self compensation and auxiliary compensation in seed metering device, in order to solve the issue of missseeding in notillage corn planter. The performance indicators of metering device at different disc speeds and seed spacing were obtained through the performance test of horizontal disc seed metering device, and the indicators included seeding qualification index, missseeding index and reseeding index. Based on these, the reseeding performance under self compensation and auxiliary compensation methods for missing seeding could be analyzed. The test result showed that when the seeding speed was from 3km/h to 7km/h and the seed spacing was 15cm, 20cm and 25cm, the qualification index of the metering device was decreased with the increase of the seeding speed, and the smaller the seed spacing was, the lower the qualified rate was at the same speed; the missseeding index was increased with the increase of seeding speed, and the smaller the seed spacing was, the higher the missseeding index was. The analysis of the performance of self compensation for missseeding shows that after detecting missseeding signals at the seeding metering port and carrying out accelerated reseeding, the actual seed spacing LPR was larger than 1.5L, and the reseeding spacing was still missseeding, despite that the missseeding spacing was lowered, where precise missing reseeding function could not be realized. In case the missseeding signal could be detected before the seed left the metering hole, and the acceleration preparation was made in advance, then the missseeding could be realized. Selfcompensation for missed seeding was greatly affected by seeding speed and seeding spacing. When the seeding spacing was 20cm and 25cm and the seeding speed was not more than 5km/h, the qualified rate of reseeding was above 88%. When the seeding spacing was 15cm or the seeding speed was above 5km/h, the qualified rate of reseeding was lower. The performance of variable speed seeding would gradually weaken with the increase of seeding speed. Through the analysis of the performance of the auxiliary compensation device for missseeding, at the seeding speed of 3~7km/h and the grain spacing of 15~25cm, the success rate of reseeding was above 89%, and the qualified rate of reseeding was above 96% at the seeding speed of 5km/h or below. It was concluded that the reseeding position should be ensured to be precise, where the installation position of the compensation device for missseeding should be reasonably designed. In the meantime, after reasonably design of the compensation reseeding device installation indicators, the t (response time) and vb (linear speed of compensation device seeding discs) should be controlled to realize the precise control of the reseeding position, as they may be affected by seeding speed, seeding spacing, seeding disc linear speed and the seeding angle.
