A Pneumatic Dibbling Machine for Plastic Mulch

A machine capable of placing planting holes for a wide variety of spacings in plastic mulch beds with very little physical reconfiguration was designed and tested. The three-point hitch mounted machine was demonstrated with two horticultural crops which have widely varying within-row and between-row spacing requirements: onions and potatoes. The piercing mechanisms were powered by pneumatic cylinders, and the on-board controls allowed users to adjust the number and spacing of holes. Switches enabled between-row spacing to vary by placing from one to four planting holes across a standard 76-cm (30-in.) bed. For the algorithm used, a dial was set to create the within-row spacing between 15 and 61 cm (6 and 24 in.). These control settings and a fixed tractor speed acted as inputs to a microprocessor which calculated hole placement frequency and initiated cylinder activation.