design, development and evaluation of a pneumatic seeder for automatic planting of seeds in cellular trays

for planting fine seeds in cellular trays, an automatic pneumatic seeder was designed, constructed and evaluated. catia software was used to design and analysis the system parts of the seeder. different parts of the seeder, including vibrating seed hopper, vacuum boom, seed picking nozzles, seed tube, pneumatic system and electronic control unit for automation of the seeder, were designed and constructed. the area of nozzle orifice was used to calculate the required pressure of nozzle tip. the seeder was evaluated using two sizes of trays. experiments were performed with five replications and the error of planting the seeds in the 105 and 390-cellular trays were 1.9 and 0.46 percent, respectively. the time of planting for 105 and 390 cellular trays reduced from 20 min (for manual seeding) to 35 s and from 90 min to 160 s, respectively.