Design and Dynamic Response Analysis of a Small-Scale Seed Rope Planter for Small-Field Agricultural Environments

To address the limited adaptability of conventional large-scale seeders in small-field and confined agricultural environments, the low efficiency of manual sowing, and the challenges of precision seeding of small-sized seeds, a small-scale seed rope planter integrating furrow opening, seed rope laying, soil covering, and compaction was developed. The planter was designed to meet the operational requirements of small-field and confined environments, and its dynamic response characteristics were investigated. The effects of original ground-surface roughness, planter vibration, and operator-applied pushing force on furrow-opening depth and soil-covering thickness were characterized through theoretical modeling and seeding performance experiments. Time- and frequency-domain analyses were conducted to characterize the dynamic behavior of the seeding system, and a three-input, two-output multi-input multi-output (MIMO) transfer function model was identified using the Prediction Error Method (PEM). The results showed that the seeding system was predominantly influenced by low-frequency disturbances and exhibited coupled dynamic responses among the input and output variables. The identified model achieved fit percentages of 83.97% for furrow-opening depth and 84.06% for soil-covering thickness in pushing condition, and 82.09% and 82.30%, respectively, under the pulling condition. The field experiment was conducted to evaluate the practical soil-covering performance of the planter. The measured soil covering thickness at 50 randomly selected sampling points ranged from 18.11 to 27.84 mm, with a mean value of 23.09 mm, a standard deviation of 2.35 mm, and a coefficient of variation of 10.22%. These results indicate that the developed seed rope planter can maintain a relatively uniform soil coverage under actual field conditions, providing a theoretical basis for the design of rope-seeding machines.