To solve the problem of large sowing amount and poor sowing uniformity for millet, according to the physical characteristics of the millet seed and its sowing agronomic requirements, an electromagnetic vibration type fine and small-amount seeder was designed, and the main technical parameters of the seeder were determined, in order to realize the functions of furrow opening, electronically controlled seed metering, soil covering and pressing. Based on the principle of electromagnetic vibration, an electromagnetic vibration type seed metering device was designed to achieve uniform seeding of the millet seed with a small sowing amount; a seeding amount electronic control device was designed using an STM32 microcontroller, which realized the switching to sowing agronomic mode and the adjustment of the seeding amount with sowing operation speed; a vibration experimental bench was set up to simulate the vibration state of field operation, and studies on the seeding performance and vibration damping of the seed metering device by the isolation spring were carried out, as well as field sowing tests for verification. When the working voltage of the seed metering device is 80-160 V, the coefficients of variation for seeding uniformity per row and for total seeding uniformity are not greater than 3.57% and 2.39%, respectively, and the seed damage rate is less than 0.5%. The installation of isolation springs can increase the maximum vibration acceleration of the seed metering device by 10.61-28.20%, significantly reducing the impact of external vibrations on the seed metering device. Within the range of suitable sowing operation speeds, the electronic control device can meet the seeding amounts along with sowing operation speed in the 6, 7.5 and 9 kg/hm2 sowing agronomic modes, and the coefficient of variation for seeding uniformity per row, for total seeding uniformity and for sowing uniformity are not greater than 4.63%, 2.48% and 23.38%, respectively. This study provides a reference for the development of sowing machinery for millet crop.

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 degrees-81.6 degrees, 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.

The new technique of filming in autumn and planting directly through the plastic film in spring is an effective method for water-saving and drought-resistant commercial potato production. However, there are currently no supporting film-drilling seeders available. To address this, a new potato seeder machine has been specifically designed for planting potatoes in the dryland, hilly, and mountainous areas of northwest China. This machine can perform top mulching and hole planting in both the autumn and spring seasons. This innovative potato seeder accomplishes several tasks simultaneously: seeding, inoculation (if desired), hole punching through the mulch film, seed placement, and soil covering. The machine features an optimized spoon-chain seeder with an eccentric coupling mechanism that ensures the hole-punching device stays perpendicular to the ground throughout planting, minimizing damage to the mulch film. Additionally, a dedicated seeding valve opening and closing mechanism was designed to extend the opening time of the hole-forming device's movable mouth beyond the potato's falling time, guaranteeing successful seed placement. Furthermore, a soil-covering device specifically designed for use with mulch film ensures proper soil retention after seeding. Through computer-aided design (RecurDyn V9R5 software) analysis, the hole-punching device's penetrating angle was optimized to minimize the tearing of the mulch film during entry into and exit from the soil. Rigorous field testing demonstrated the machine's effectiveness. The seeder achieved a 92% success rate for proper planting depth, an 88% success rate for accurate seed potato spacing, a 98% success rate for avoiding overplanting, and a 99% success rate for eliminating missed planting spots. These field test results meet or exceed national and industry standards, validating the machine's design goals. In essence, this innovative potato seeder, with its eccentric coupling mechanism, offers a one-pass solution for potato seeding, inoculation (optional), planting, and soil covering, significantly improving efficiency.