Design and experiment on electronic control system for plot seeder

In order to improve the precision and efficiency of plot seeders, an electronic control system was developed, which conld increase the accuracy and scientificity, decrease cost of breeding experiment in the field. A stepping motor was applied to control the rotation angle of cone compartment tray of the metering device. The centrifuging distributor was controlled by a direct-current motor, and two speed sensors were used for monitoring working speed to reduce the influence of skidding which caused inaccuracy of seeding length. The indoor experiment results showed that the inaccuracy for the rotation angle of cone compartment tray was less than 0.24% at all kinds of rotating speed; according to different seeds, the best distributor rotating speed was different. The speed respectively was 1?560 r/min for colza seeds, 1?020 r/min for Chinese cabbage seeds, 1?560 r/min for sesame seeds, 780-1?020 r/min for green bean seeds. Seeding in such speed could make sure that the coefficient of variation between rows was minimal and the best coefficient in rows was achieved. When the working speed was higher than 2.5 km/h, the coefficient of variation in the same rows was less than 15.4%. When the working speed was lower, the coefficient of variation in the same rows was higher.