Apple orientation on two conveyors: performance and predictability based on fruit shape characteristics.
Throop, J. A., Aneshansley, D. J., Upchurch, B. L. and Anger, B.
Transactions of the ASAE. Volume 44, Number 1, 2001. Pages 99-109.
2001
บทคัดย่อ
Two sizes of 11 apple cultivars were placed on a bicone conveyor used in commercial sorting machines and on an experimental conveyor. In less than 18 seconds, apples were oriented into one of two modes, either parallel (desired) or non-parallel (undesired) to the stem/calyx axis. The commercial conveyor gave desired orientation to 94% of 88 Washington State Red Delicious apples but to only 4% of 772 apples from eastern cultivars. The experimental conveyor gave desired orientation to 83.4% of the apples from cultivars normally produced in the eastern USA but to only <1% of Washington State Red Delicious apples. Cortland, Empire, small Fuji, Jonagold, McIntosh, and Rome apples, when placed so that they rotated perpendicular to the stem/calyx axis, moved to the desired orientation 95 to 100% of the time. Only 82% of large Fuji apples moved to the desired orientation. In addition, 47 to 80% of the Golden Delicious, Granny Smith, Crispin, Eastern Red Delicious, and Gala apples, when placed to rotateon the undesired axis, moved to the desired orientation. Washington State Red Delicious apples, when placed on the experimental conveyor to rotate on the desired axis, changed to the undesired orientation for 87 of 88 apples. Linear discriminate analysis was performed using up to 19 of the shape factors measured from silhouette images of the side and top views of each apple. The height-width ratio of the side view of the apples predicted both desired and undesired orientation on both conveyors almost as well as any combination of shape factors. Cortland, Empire, small Fuji, Jonagold, McIntosh, and Rome apples have height-width ratios of approximately 0.8, and all oriented to the desired axis on the experimental conveyor and to the undesired axis on the commercial conveyor. Washington State Red Delicious apples had height-width ratios of 1.03 and oriented to the undesired axis on the experimental conveyor and to the desired axis on the commercial conveyor. Apples with average height-width ratios between 0.8 and 1.0 were inconsistent, but more than half of these apples oriented correctly on the experimental conveyor. The commercial conveyor oriented elliptically shaped objects to rotation about an axis passing through the centre of gravity and where the centre of gravity is lowest. This axis typically corresponded to the stem/calyx axis of the Washington State Red Delicious apples. The experimental conveyor oriented elliptically shaped objects to rotation about the shortest axis where the contact point on the powered roller was the highest. For both devices, the height-width ratio from the side views of each apple was a measure of this ellipticity.