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.
Storage System Layout
Single Row Elevation View
Height=35 ft
(10 Bins)
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
Bin
Length= 525 ft
(75 Bins)
Storage Layout View (Top View)
Row 1
Row 2
Storage/Retrieval
Machine
P/D
Station
P/D
Station
Row 3
P/D
Station
Row 20
P/D
Station
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