Design and evaluation of a pneumatic metering mechanism for power tiller operated precision planter

Power tiller is the most common prime mover in medium and marginal farms due to its light weight, compact design and low cost. Many attachments for power tiller have been developed except for precision pneumatic planter which is necessary to plant irregular, small and expensive seeds. In the present work, a pneumatic seed metering mechanism was designed for the power tiller operated 3-row precision planter. It was tested for planting soybean, pigeon pea and corn seeds at 20 cm spacing. The best design and operating parameters of the modular seed metering device were identified by conducting experiments on the sticky belt test stand considering various performance indices on the basis of pareto dominance criterion. The seed metering disc having 8 holes of 3.5 mm diameter on pitch circle diameter of 116 mm and operated at 0.11 ms(-1) peripheral speed and 6 kPa suction were found to be the best combination of design and operating parameters for the precise metering of seeds. More than 67% of the seeds got distributed in the range of 15-20 cm spacing.