Abstract:A hole fertilization system was designed to satisfy the technology demand on precise hole fertilization agriculture which applied a discrete element method software EDEM to simulate the hole fertilization controlling device. The result demonstrated that the mean hole distance was 24.90cm, 23.79cm and 23.28cm, respectively, when planter speed was 3km/h, 5km/h and 7km/h, and the soil opener working performance of the hole fertilization system was weakened as the speed of the planter was increased. Based on the hole fertilization controlling algorithm, the hole fertilization position controlling was achieved by adjusting the time interval between the seed out of the seed outlet and the fertilizer out of the fertilizer outlet (t3) and controlling the horizontal distance between the fertilizer and the seeds (a);the hole fertilization amount controlling was achieved by adjusting the opening and closing frequency of the fertilizer axis speed and the duckbill valve. Based on the orthogonal rotation design test of quadratic regression and the response surface methodology, the speed of the seeding machine, the opening and closing angle of the duckbill valve and the installment height of the hole fertilization device were taken as test factors, the precision of hole distance and the precision of the fertilization amount were taken as test indicators to implement the orthogonal test. The result showed that the precision of hole distance and the fertilization amount was 86.03% and 84.60%, respectively, when the speed of the seeding machine, the opening and closing angle of the duckbill valve and the installment height of the hole fertilization was 7km/h, 33.37° and 17.30cm when the hole fertilization was at optimum working performance. By testing on the precision of hole distance and the fertilization amount with the opening and closing angle and the installment of 33.37° and 17.30cm, the speed of the planter as 3km/h, 5km/h and 7km/h, the field validation test result was similar to the theoretical result. Furthermore, the precision of the hole fertilization controlling system was decreased slightly as the moving speed was increased and the precision of hole distance and the fertilization amount was 84.76% and 87.20%, respectively, which can satisfy the precision and amount controlling demands on the hole fertilization of corn.
