Traction Force, Sowing Quality, and Deformation Characteristics of the Coulter of a Grain–Fertilizer–Grass Seeder

The development of restoration technology and meadows, improvement of run-down pastures, and productivity improvement of old crops of perennial grasses is an urgent problem in agriculture. The tillage traction force in seeder designing and manufacturing is an important indicator of energy efficiency. The objective of this work is to reduce traction force and ensure seeding depth uniformity by justifying the optimal chisel parameters of a grain–fertilizer–grass seeder for direct seeding in sod. The Box–Behnken method was applied to investigate the traction force dependence on the seeder velocity, seed embedding depth, chisel width, and mounting angle. The obtained optimal parameters of coulters were justified by the finite element method. Structural and technological parameters were checked using the smoothed-particle hydrodynamics method on the deformation and wear of the seeder working body. The revealed optimal coulter parameters were as follows: chisel width was 20–20.97 mm, chisel length was 145–148.9 mm, mounting angle was 75°–81.6°, and achieved minimum traction force was 720 N. These parameters ensure the quality of grass seed embedding in the sod. The theoretical data of traction force (8.27–8.39 kN) are in accordance with the experimental (8.28–8.63 kN) data under field conditions. These findings are efficient in agrotechnical and mechanical predictions regarding the occurrence of chisel residual stresses and the working lifetime of the part.