Fruit grading robot

A grading robot for deciduous fruits such as peaches, pears, and apples to automatically provide fruits from containers and to inspect all sides of fruit was developed. The grading robot consists of a 3 DOF manipulator, 12 suction pads as end-effector, 12 color TV cameras, and 28 direct lights. 12 fruits were sucked up by a manipulator at a time and 12 bottom images of fruits were acquired during the manipulator moving to trays on a conveyor line. Before releasing the fruits to the trays, 4 side images of each fruit were acquired by rotating the suction pads for 270 degrees. The stroke of the manipulator was about 1.2 m and it took about 4.3 seconds to move back to the initial position that meant that this robot could grade three fruits per second.