BROKEN CASE PICKING SYSTEMS

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World-Class Warehousing and Material Handling

Person-aboard ASRSs are far and away the most expensive PTS equipment alternative. Hence there must be enough storage density and/or productivity improvement over cart and tote picking to justify the invest ment. Also, because vertical travel is slower than horizontal travel, typical picking rates in person-aboard operations range between 40 and 250 lines per person-hour. The range is large because there are a large number of oper ating schemes for person-aboard systems. Person-aboard systems typically are appropriate for slow-moving items where space is fairly expensive. Robotic Item Picking Robotic picking vehicles (Figures 7.41 and 7.42) travel automatically through a sequence of picking locations, receiving power and communication from rails in the floor and ceiling. The vehicles are equipped with a small carousel to permit order sorting, accumulation, and containment. The carousel travels up and down a mast on the robot as it traverses the picking aisle(s). The robot can automatically extract a storage drawer from a storage location onto the picking vehicle. The robot’s arm is guided by an onboard vision system to direct item picking from a specific storage compartment in a storage drawer. Only in rare instances are robotic item picking systems justifiable.

Figure 7.41 Robotic item picking

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