DESIGN AND EXPERIMENTAL STUDY OF A CONTROL SYSTEM FOR SYNCHRONIZED CORN SEEDING AND HOLE FERTILIZATION

To solve the problems of slow system response speed and poor uniformity of seeding and fertilizer application, this paper designs a control system for synchronized corn seeding and precision hole fertilization. A sliding mode control method with integral variable structure and disturbance observer composite (ISMDO-SMC) is proposed. Furthermore, a three-factor, five-level quadratic orthogonal rotation combination experiment was conducted to develop a mathematical model for parameter optimization using a multi-objective variable optimization method. Simulation results from four algorithms were compared, revealing a regulation time of 0.42 seconds, a recovery time to steady state of 0.13 seconds, and a descending rotational speed of 2.5 r/min, which demonstrates the strongest dynamic response and stability. Moreover, the optimal parameter combination was determined to be the forward speed of 2.8 km/h, the fertilizer discharge shaft speed of 42 r/min, and the fertilizer discharger opening of 5.5 mm, resulting in the fertilizer application error of 1.7 g and the seed-fertilizer spacing error of 2.2 mm. The results of this study provide a theoretical basis for achieving efficient and stable seeding and fertilization operations.