Warehouse Model at the Athletic Shoe Company

Anh Pho & Gail Savage

Simulation & Modeling Analysis (DSES 6220)

Professor: Ernesto Gutierrez-Miravete

12-21-00

Introduction

Project is based on Case #3 in Harrell– Warehouse modeling problem

Project involves 2 tasks– Designing shoe storage area– Modeling customer shipments process & stock

receiving process

Shoe Storage System

Needs to fit in physical space Needs to hold 3,000,000 pairs of shoes with

3,000 different SKUs Designed bin storage able to hold 112 prs.

Single Row Elevation View

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75

Storage Layout View (Top View)

Height=35 ft (10 Bins)

Length= 525 ft (75 Bins)

Storage Bin

Storage/RetrievalMachine

Row 1

Row 2

Row 3

Row 20

P/DStation

P/DStation

P/DStation

P/DStation

Storage System Layout

Simulation Model

Shipping Process– Entity is the customer order– Filled by a single filler

Stock Receiving Process– Entity is the receiving order– Stocking is done by a single “put away guy”

Assumptions

All SKUs are equally shipped Warehouse is fully stocked at beginning Receiving arrival rate and shipping arrival

rate are the same No down time Fillers and “put away guys” have the same

service rate Warehouse runs 24 hours/day

The Simulation Model Reduced model

Shipping Rate (pairs/day) 7,000 – 8,000

Inventory Requirement (pairs) 6000

Quantity per Shipping Order (pairs/order) 1 – 4

SKU per Order (Sku/order) 1 – 4

Receiving Rate (pairs/day) 7,000-8,000

Model elements

Locations Resources

Customer order pickup Fillers

Inspection table Packers

Packing queue Inspectors/Sorters

Packing table Put away guys

Pickup tables

Put away tables

Receiving table

Shipping queue

Stocking queue

Verification/Validation

Verification– Found syntax errors– Watch model animation– Semantic errors– Watch selective trace runs

Validation– Watch model animation behavior– Counter values– ProModel demo program

Performance Metrics

Metric Goal Simulation Results

Resource Utilization At least 80% Above 80%

Inventory Level Approx. 6,000 prs 5,738 prs.

No. prs.Shipped/Day

7,000 – 8,000 prs 7,656 prs

Resource Utilization

Conclusion

Storage area was designed Model was created, verified and validated Meets all current performance metrics Can be used to perform “what ifs” for

future demands