IE5600 – Applied Programming for Industrial Systems

Tan Wee Kek, tanwk@comp.nus.edu.sg 1

IE5600 – Applied Programming for Industrial Systems
AY 2021/22 Semester 2
Individual Assignment 2 - PyWarehouse


Objectives

At the completion of the individual assignment, you should:

1. Develop a better understanding of how to apply the computational problem solving
process to a complex problem that requires the use of appropriate data structures and
algorithms.

2. Implement procedural and object-oriented programming paradigms in Python.

3. Apply appropriate user-defined data structures and algorithms.


General Requirements

You are required to develop a Python program known as PyWarehouse which is essentially
a warehouse management system for a typical manufacturing and import/export company.
PyWarehouse will manage the storage locations in the warehouse, the inventory items stored
in the storage locations as well as the inbound and outbound movement of these inventory
items.

Figure 1 shows a layout plan of a typical warehouse divided into several zones such as
reception, loading & unloading, picking and storage. As illustrated in the layout plan, the
storage zone is further organised into multiple storage racks.

Figure 2 shows a hypothetical layout plan based on Figure 1 which will constitute the actual
warehouse that PyWarehouse would be managing. In this hypothetical layout plan, the
storage racks are numbered sequentially with the odd numbered racks on one side and the
even numbered racks on the other side.

Each storage rack is further divided into one or more levels of storage spaces known as
shelves. Each storage shelf can be further divided into one or more compartments known as
storage bins. Each storage bin is characterised by various key parameters such as length,
width, depth, volumetric space, and load capacity. Refer to Figure 3 for a three-dimensional
view of a typical storage rack. An inventory item may only be allocated to a storage bin of
sufficient volumetric space and adequate load capacity. In addition, no part of the item should
protrude out of the storage bin, i.e., the length, width and depth of an item should all be less
than or equal to the corresponding dimensions of the storage bin. For example, an item might
meet the volumetric space and load capacity of a storage bin but the depth might be too high.
In this case, the item should not be allocated to this bin.
IE5600 – Applied Programming for Industrial Systems

Tan Wee Kek, tanwk@comp.nus.edu.sg 2

Figure 1 – Layout plan of a typical warehouse.


Figure 2 – Hypothetical layout plan of PyWarehouse.





Loading &
Unloading
Reception
Picking,
Putaway,
Packing
Storage
R
ac
k
1
R
ac
k
3
R
ac
k
11

R
ac
k
7
R
ac
k
9
R
ac
k
5
R
ac
k
2
R
ac
k
4
R
ac
k
12

R
ac
k
8
R
ac
k
10

R
ac
k
6
Forklift
Parking
X
IE5600 – Applied Programming for Industrial Systems

Tan Wee Kek, tanwk@comp.nus.edu.sg 3

Figure 3 – Three-dimensional view of a typical storage rack (with numbering of rack, shelves and bins).

In general, the load capacity of a storage bin will remain the same or decrease as the shelf
level increases in order to maintain the overall stability of the storage rack. In other words,
heavier items should be stored on lower storage shelves. If a storage bin is shared among
multiple items, it is necessary to check that the odd-shaped volumetric space remaining is
sufficient and a heavier item is not stacked on top of a lighter item. See the two examples
depicted in Figure 4.


Figure 4 – Sharing of storage bins by multiple items.

Existing Item
Bin 2
Existing Item
Bin 1

New Item that is lighter weigh

Length
Width
Depth
Remaining odd-shaped volumetric space
Rack 1
Shelf 1
Shelf 2
Shelf 3
Bin 1
Bin 2
Bin 3
Rack 1 Shelf 2 Bin 2
IE5600 – Applied Programming for Industrial Systems

Tan Wee Kek, tanwk@comp.nus.edu.sg 4
Design and Implementation of Classes

Design a set of suitable classes together with the necessary inheritance and/or association
relationships to represent the warehouse shown in Figure 2 that PyWarehouse would be
managing. You do not need to draw a UML class diagram as part of the deliverable
submission. You are only required to define the classes in a Python module and import this
module for use in the actual PyWarehouse program.

You need to take into consideration that each storage rack consists of multiple storage shelves
and each shelf is further divided into multiple storage bins as shown in Figure 3 and 4.

In addition, the classes also need to be able to represent inventory items that are stored in the
warehouse. For simplicity, PyWarehouse is only required to track inventory items in broad
lot quantity that are packaged in carton boxes or pallets. In other words, each unit of an
inventory item manifest as a single carton box or pallet stored at a particular storage bin.
Other than the physical dimensions, weight and quantity, you only need to keep track of the
stock keeping unit (SKU) code of an item together with its name. Here is an example of an
inventory item record with reference to the storage rack depicted in Figure 3:

• SKU Code – MASK
• Name – COVID-19 3-Ply Face Mask (100 Boxes)
• Dimensions (LxWxD) – 100 cm x 100 cm x 100 cm
• Volumetric Space – 1,000,000 cm3
• Weight – 20 kg
• Quantity – 10:
o 1 – Rack 1 Shelf 1 Bin 1
o 2 – Rack 1 Shelf 1 Bin 1
o 3 – Rack 1 Shelf 1 Bin 2
o 4 – Rack 1 Shelf 1 Bin 2
o 5 – Rack 1 Shelf 1 Bin 3
o 6 – Rack 1 Shelf 1 Bin 3
o 7 – Rack 1 Shelf 2 Bin 1
o 8 – Rack 1 Shelf 2 Bin 1
o 9 – Rack 1 Shelf 2 Bin 2
o 10 – Rack 1 Shelf 2 Bin 2

It is mandatory to apply the object-oriented programming paradigm to this assignment.
Otherwise, you would only be awarded 50% of the marks for the use cases.

IE5600 – Applied Programming for Industrial Systems

Tan Wee Kek, tanwk@comp.nus.edu.sg 5
Use Cases

Use the classes that you have defined to implement the following use cases for PyWarehouse
without the use of any Python modules. In other words, your program should NOT contain
any import statement unless you are importing your own user-defined module(s).

S/N Use Case Use Case Description/Business Rules
1 Create Storage Rack
(2 marks)
• Create a new storage rack in the warehouse.
• You may assume that all storage bins in a rack has the
same parameters.

Sample Input:
• Rack Number – 1
• Number of shelves – 3
• Number of bins per shelf – 3
• Bin Length – 200 cm
• Bin Width – 200 cm
• Bin Depth – 200 cm
• Computed Volumetric Space for each Bin –
8,000,000 cm3
• Bin Load Capacity – 50 kg

Sample Output:
• Created the following storage bins:
o Rack 1 Shelf 1 Bin 1
o Rack 1 Shelf 1 Bin 2
o Rack 1 Shelf 1 Bin 3
o …
o Rack 1 Shelf 3 Bin 3
2 Create Inventory Item
(1 marks)
• Create a new inventory item record.

Sample Input:
• SKU Code – MASK
• Name – COVID-19 3-Ply Face Mask (100 Boxes)
• Length – 100 cm
• Width – 100 cm
• Depth – 100 cm
• Computed Volumetric Space for each Unit –
1,000,000 cm3
• Weight – 20 kg
IE5600 – Applied Programming for Industrial Systems

Tan Wee Kek, tanwk@comp.nus.edu.sg 6
S/N Use Case Use Case Description/Business Rules
3 Add Inventory
(4 marks)
• Add one or more units of an inventory item.
• For each unit of inventory item, the program should
search the warehouse for all available storage bins and
recommend them to the user for selection.
• The user should only select one storage bin for each
unit.
• If no suitable storage bin is available, print an error
message and stop processing the current and
subsequent units.
• It is important to perform a check on whether a storage
bin is able to accommodate the item based on the
dimensions, volumetric space and weight.

Sample Input:
• SKU Code – MASK
• Quantity – 2
• Unit 1:
o Choose storage bin:
 Rack 1 Shelf 1 Bin 1
 Rack 1 Shelf 1 Bin 2
 Rack 1 Shelf 1 Bin 3
 …
 Rack 1 Shelf 3 Bin 3
o User selects – Rack 1 Shelf 1 Bin 1
• Unit 2:
o Choose storage bin:
 Rack 1 Shelf 1 Bin 1
 Rack 1 Shelf 1 Bin 2
 Rack 1 Shelf 1 Bin 3
 …
 Rack 1 Shelf 3 Bin 3
o User selects – Rack 1 Shelf 1 Bin 1

Note that for MASK, each storage bin in Rack 1 can store
8 units based on the volumetric space. But due to the load
capacity constraint (50 kg), we can only allocate two units
of MASK (2 x 20 kg) to each bin.
IE5600 – Applied Programming for Industrial Systems

Tan Wee Kek, tanwk@comp.nus.edu.sg 7
S/N Use Case Use Case Description/Business Rules
4 Remove Inventory
(1 mark)
• Remove one or more units of an inventory item.
• The program should display the list of all available
units and the corresponding storage bin to the user for
selection.
• The user should select the required units by entering
the corresponding storage bin number.

Sample Input:
• SKU Code – MASK
• Quantity – 1
• Choose unit:
o 1 – Rack 1 Shelf 1 Bin 1
o 2 – Rack 1 Shelf 1 Bin 1
• User select 1

Note that in use case 3, we added 2 units of MASK to
Rack 1 Shelf 1 Bin 1.
5 Query Inventory Item
(1 mark)
• Display information about an inventory item.
• The available inventory units and their corresponding
storage bin should also be displayed.

Sample Input:
• SKU Code – MASK

Sample Output:
• SKU Code – MASK
• Name – COVID-19 3-Ply Face Mask (100 Boxes)
• Dimensions (LxWxD) – 100 cm x 100 cm x 100
cm
• Computed Volumetric Space for each Unit –
1,000,000 cm3
• Weight – 20 kg
• Quantity On Hand – 1
o 1 – Rack 1 Shelf 1 Bin 1

Note that in use case 3, we added 2 units of MASK to
Rack 1 Shelf 1 Bin 1 and in use case 4 we removed 1 unit
of MASK.
IE5600 – Applied Programming for Industrial Systems

Tan Wee Kek, tanwk@comp.nus.edu.sg 8
S/N Use Case Use Case Description/Business Rules
6 Query Storage Bin
(1 mark)
• Display information about a storage bin.
• The available inventory items currently in the storage
bin should also be displayed.

Sample Input:
• Rack – 1
• Shelf – 1
• Bin – 1

Sample Output:
• Dimensions (LxWxD) – 200 cm x 200 cm x 200
cm
• Computed Volumetric Space – 8,000,000 cm3
• Load Capacity – 50 kg
• Inventory Items:
o 1 – MASK

Note that in use case 3, we added 2 units of MASK to
Rack 1 Shelf 1 Bin 1 and in use case 4 we removed 1 unit
of MASK.


Deliverable Submission

The assignment deliverable to be submitted to the LumiNUS Files tool are to be placed in a
single zip archive file with the following folders structure:

• source subfolder containing:
o All Python source files that constitute your program.
o The main source file containing the program entry point should be named as
pywarehouse.py, i.e., your program should be runnable with the command
python pywarehouse.py

Upload this zip archive file to the designated LumiNUS Files tool folder: “Deliverables
Submission > Individual Assignment 2”.

Your deliverables must be submitted latest by Sunday, 1 May 2022, 11:59 pm. No
assignment will be accepted for assessment after this date/time and you will be awarded 0
marks. In addition, please take note that the LumiNUS Files tool submission folder will be
closed after the submission date/time.



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