Dibber Drill for Precise Placement of Seed and Granular Pesticide

Abstract The objective of the work was to produce a lightweight dibber drill, employing simpler mechanisms than previous experimental designs, capable of precisely metering small doses of granular pesticide with each seed. A simple, novel solution to the problem of transfer, acceleration and delivery of seeds and granules from a slow speed, 0·2 m/s, cell wheel metering system into a high-speed, 1·8 m/s, dibber placement system using a venturi air jet device was developed. A compact dibber wheel employing pneumatically actuated, rapid-acceleration dibber plungers was also produced. High-speed video was used for visualizing and refining seed transfer trajectories and dibber plunger timing control. Using lettuce as a benchmark crop, the new drill performed equally well (84% emergence) to its more complicated predecessor (82%) and significantly better than a conventional coulter drill (71%).