Logistic Management 11 02 2022

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LOGISTICS MANAGEMENT A.Y. 2021-22 - Prof.Marco Melacini 2nd call - February 11th 2022 EXERCISE 1 2 lOMoARcPSD|20562176 EXERCISE 1.1 Consider an AS/RS warehouse whose layout is shown in Figure 1, consisting of 4 storage aisles with double-deep storage racks. The I/O system is located at the first level. A conveyor connects storage area to 4 picking stations. The unit loads (ULs) handled by the AS/RS warehouse are palletized ULs. At the picking stations, the pickers pick cartons from the ULs. Assuming the following additional information: number of storage levels: 10; number of storage columns: 30; gross size of each storage location (= storage bay): 2,600 (depth) * 1,800 * 1,600 (height) mm; each storage location can hold 4 ULs; number of forks per each S/R machine: 1; item allocation to the storage locations: random; horizontal speed: 2.5 m/s; vertical speed: 1.1 m/s; fixed time for positioning: 4 s; fork cycle time: 5 s; acceleration + deceleration delay: 6 s; S/R machines availability: 100%; the required UL is never stored behind another UL (assumption only for Exercises 1.1 to 1.3); the expected cycle time can be estimated through FEM 9851 rule, Estimate the average single command cycle time. Enter your answer 3 EXERCISE 1.2 Considering the same setting described in Exercise 1.1, estimate the average dual command cycle time. Enter your answer 4 EXERCISE 1.3 Considering the AS/RS warehouse described in Exercise 1.1 and the following assumptions: the warehouse works 3 shifts/day; the storage activity is performed every day during the third shift; carton picking is performed every day during the first and second shift; on average, the number of customers orders is 10 orders/hour; on average, each order consists of 10 order lines, with 3 cartons per order line; in 90%…