FRESHâMARKET QUALITY TREE FRUIT HARVESTER PART I: SWEET CHERRY

Abstract

A twounit mechanical harvester was developed to harvest freshmarket quality sweet cherries (Prunus aviumL.). Units were essentially mirror images. On each unit the harvester operator used joysticks to position and engage a rapiddisplacement actuator (RDA) on main scaffolds to effect fruit removal. Catching conveyors were designed to intercept fallingfruit without damage and elevate the fruit to a collecting conveyor. Cushioned catcher pans on each unit were used to sealaround the trunk and connect the two units. Main scaffolds were inclined to reduce damage as cherries fell to the catchingsurface. Ethrel (2chloroethyl phosphonic acid) was used to reduce the fruit retention force of mature cherries to enableremoval without stems or damage. The experimental harvester demonstrated potential for harvesting stemless sweet cherrieswith freshmarket fruit quality comparable to commercial handpicked cherries. The catching/collecting system was effectivewith low damage inflicted to the cherries. About 90% of the cherries were remove from the tree and of those removed, 88%were collected and containerized. These levels are expected to increase with proper tree training and appropriate sizedcatching surfaces. Harvest rate downtherow ranged from 85 to 158 trees/h with harvester capacity up to 1590 kg/h(3500 lb/h).