04 material handling - part4

Arif Rahman – The Production Systems 1
Slide 4
Material Handling
Arif Rahman, ST MT

Arif Rahman – The Production Systems
Storage System
Performance And Location
Strategies
2

Function – to store materials (e.g., parts,
work-in-process, finished goods) for a
period of time and permit retrieval when
required
Used in factories, warehouses, distribution
centres, wholesale dealerships, and retail
stores
Important supply chain component
Automation available to improve efficiency
Storage Systems
3

Type Description
Raw
materials
Raw stock to be processed (e.g., bar stock, sheet
metal, plastic moulding compound)
Purchased
parts
Parts from vendors to be processed or
assembled (e.g., castings, purchased
components)
Work-in-
process
Partially completed parts between processing
operations or parts awaiting assembly
Finished
product
Completed product ready for shipment
Rework and
scrap
Parts that are out of specification, either to be
reworked or scrapped
Types of Materials Typically Stored in Factory
4

Type Description
Refuse Chips, swarf, oils, other waste products left over
after processing; these materials must be
disposed of, sometimes using special
precautions
Tooling Cutting tools, jigs, fixtures, molds, dies, welding
wire, and other tooling used in manufacturing and
assembly; supplies such as helmets, gloves, etc.,
are usually included
Spare parts Parts are needed for maintenance and repair of
factory equipment
5

Type Description
Office
supplies
Paper, paper forms, writing instruments, and
other items used in support of plant office
Plant records Records on product, equipment, and personnel
6

Storage capacity - two measures:
¤ Total volumetric space
¤ Total number of storage compartments (e.g., unit loads)
Storage density - volumetric space available for storage
relative to total volumetric space in facility
Accessibility - capability to access any item in storage
System throughput - hourly rate of storage/retrieval
transactions
Utilization - the proportion of time that the system is actually
being used for performing storage and retrieval operations
compared with the time it is available
Availability (reliability) – the proportion of time that the
system is capable of operating (not broken down) compared
with the normally scheduled shift hours
Storage System Performance: Measures
7

System throughput is limited by the time to
perform a S/R transaction
Elements of storage transaction:
¤ Pick up load at input station
¤ Travel to storage location
¤ Place load into storage location
¤ Travel back to input station
Elements of retrieval transaction:
¤ Travel to storage location
¤ Pick item from storage
¤ Travel to output station
¤ Unload at output station
Storage System Performance: System Throughput
8

The sum of the element times is the
transaction time that determines throughput
of the storage system
Throughput can sometimes be increased by
combining storage and retrieval transactions
in one cycle, thus reducing travel time; this is
called a dual command cycle
When either a storage and a retrieval
transaction alone is performed in the cycle, it
is called a single command cycle
Storage System Performance: System Throughput
9

Randomized storage –
¤ Incoming items are stored in any available
location
¤ Usually means nearest available open
location
Dedicated storage –
¤ Incoming items are assigned to specific
locations in the storage facility
Storage Location Strategies
10

Typical bases for deciding locations:
¤ Items stored in item number sequence
¤ Items stored according to activity level
¤ Items stored according to activity-to-space
ratios
Storage Location Strategies
11

Less total space is required in a storage
system that uses a randomized storage
strategy
¤ Dedicated storage requires space for maximum
inventory level of each item
Higher throughput rates are achieved in a
system that uses dedicated storage strategy
based on activity level
¤ The most active items can be located near the
input/output point
¤ Compromise: Class-based dedicated storage
• Items divided into classes according to activity level
• Random storage strategy used within each class
Comparison of Storage Strategies
12

Storage type Advantage/
Disadvantage
Typical
application
Bulk storage •Highest density is
possible
•Low accessibility
•Low possible
cost/square foot
•Storage of low
turnover, large
stock or large unit
load
Rack systems •Low cost
•Good storage
density
•Good accessibility
•Palletized loads in
warehouses
Types of Storage Equipment and Methods
13

Disadvantage
Typical
application
Shelves and bins •Some stock items
not clearly visible
•Storage of
individual,
commodity items
in shelve/bins
Drawer storage •Contents of
drawer easily
visible
•Good accessibility
•Relatively high
cost
•Small tools
•Small stock items
•Repair part
14

Disadvantage
Typical
application
Automated
storage systems
•High throughput
rates
•Computerized
inventory control
system
•Highest cost
equipment
•Automated
material handling
systems
•Work in progress
storage
•Final product
warehousing and
distribution center
•Order picking
15

Bulk storage - storage in an open floor area
¤ Problem: achieving proper balance between
storage density and accessibility
Rack systems - structure with racks for
pallet loads
¤ Permits vertical stacking of materials
Shelving and bins - horizontal platforms in
structural frame
¤ Steel shelving comes in standard sizes
¤ Finding items can be a problem
Drawer storage - entire contents of each
drawer can be viewed
Conventional storage methods and equipment
16

Bulk Storage
Bulk storage
arrangements:
(a)high-density bulk
storage provides low
accessibility,
(b)bulk storage with
loads forming rows
and blocks for
improved
accessibility
17

Arrangements
18

Bulk Storage
19

Pallet Rack System
Pallet loads placed on
racks in multi-rack
structure
(a)Low cost
(b)Good storage density
(c)Good accessibility
20

Cantilever racks
Portable racks
Drive-through racks
Flow-through racks
Other Rack System
21

Cantilever Rack System
22

Drive-trough Rack System
23

Flow-trough Rack System
24

Sliding Rack System
25

Shelves and Bins
Some stock item not
clearly invisible
Storage of individual
in shelves or bins
26

Drawer Storage
Contents easily visible
Good accessibility
Relatively high cost
Small items (tools,
repair parts, etc.)
27

Automated storage
system
28

Mechanized and automated storage
equipment to reduce the human resources
required to operate a storage facility
Significant investment
Level of automation varies
¤ In mechanized systems, an operator
participates in each storage/retrieval
transaction
¤ In highly automated systems, loads are
entered or retrieved under computer control
Automated storage system
29

To increase storage capacity
To increase storage density
To recover factory floor space currently used
for WIP
To improve security and reduce pilferage
To reduce labor cost and/or increase
productivity
To improve safety
To improve inventory control
To improve stock rotation
To improve customer service
To increase throughput
Objectives of Automating Storage Operations
30

Automated Storage/Retrieval System
(AS/RS)
¤ Rack system with mechanized or automated
crane to store/retrieve loads
Carousel Storage System
¤ Oval conveyor system with bins to contain
individual items
Types of Automated Storage System
31

Feature Basic AS/RS Basic Carousel Storage
System
Storage
Structure
Rack system to support
pallets or shelf system to
support tote bins
Baskets suspended from
overhead conveyor trolleys
Motions Linear motions of S/R
machine
Revolution of overhead
conveyor trolleys around oval
track
Storage/Retrieva
l Operation
S/R machine travels to
compartments in rack
structure
Conveyor revolves to bring
baskets to load/unload
station
Replication of
Storage
Capacity
Multiple aisles, each
consisting of rack structure
and S/R machine
Multiple carousels, each
consisting of oval track and
suspended bins
Differences between an AS/RS and a Carousel Storage System
32

33

34

Automated
Storage/Retrieval System
(AS/RS)
35

36

37

AS/RS
Unit load on pallet
AS/RS with one aisle
38

Unit load AS/RS - large automated system for
pallet loads
Deep-lane AS/RS - uses flow-through racks and
fewer access aisles
Miniload AS/RS - handles small loads contained
in bins or drawers to perform order picking
Man-on-board AS/RS - human operator rides on
the carriage to pick individual items from storage
Automated item retrieval system - picks
individual items
Vertical lift storage modules (VLSM) - uses a
vertical aisle rather than a horizontal aisle as in
other AS/RS types
AS/RS Types
39

Unit load AS/RS
40

Deep-lane AS/RS
41

Miniload AS/RS
42

Man-on-board AS/RS
43

Automated item retrieval system
44

Unit load storage and retrieval
¤ Warehousing and distribution operations
¤ AS/RS types: unit load, deep lane (food industry)
Order picking
¤ AS/RS types: miniload, man-on-board, item
retrieval
Work-in-process storage
¤ Helps to manage WIP in factory operations
¤ Buffer storage between operations with different
production rates
¤ Supports JIT manufacturing strategy
¤ Kitting of parts for assembly
AS/RS Applications
45

Automated storage systems help to regain
control over WIP
Reasons that justify the installation of
automated storage systems for WIP include
¤ Buffer storage in production
¤ Support of just-in-time delivery
¤ Compatible with automatic identification systems
¤ Support of factory-wide automation
AS/RS
46

Storage structure
S/R machine
Storage modules (e.g., pallets for unit
loads)
One or more pickup-and-deposit stations
A control system that required to operate
the AS/RS
Components and Operating Features of an AS/RS
47

ny = number of load compartments along
the length of the aisle
nz = number of load compartments that
make up the height of the aisle
Capacity of the aisle = 2 ny nz
Sizing the AS/RS Rack Structure
48

x = the depth dimensions of a unit load
y = the width dimensions of a unit load
z = the height of the unit load
W = the width of one aisle of the AS/RS rack
structure
L = the length of one aisle of the AS/RS rack
structure
H = the height of one aisle of the AS/RS rack
structure
a, b, c = allowances designed into each storage
compartment to provide clearance for the unit load
and to account for the size of the supporting
beams in the rack structure
49

W = 3 (x + a)
L = ny (y + b)
H = nz (z + c)
50

Assumes:
¤ Randomized storage of loads n the AS/RS
(i.e., any compartment in the storage aisle is
equally likely to be selected for a transaction)
¤ Storage compartments are of equal size
¤ The P & D (pickup-and-deposit) station is
located at the base and end of the aisle
¤ Constant horizontal and vertical speeds of the
S/R machine
¤ Simultaneous horizontal and vertical travel
AS/RS Throughput
51

Tcs = cycle time of a single command cycle
(min/cycle)
L = length of the AS/RS rack structure (m)
vy = velocity of the S/R machine along the length
of the AS/RS (m/min)
H = height of the rack structure (m)
vz = velocity of the S/R machine in the vertical
direction of the AS/RS (m/min)
Tpd = pickup-and-deposit time (min)
AS/RS Throughput: Single Command Cycle
52

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AS/RS Throughput: Single Command Cycle
53

The S/R machine is assumed to travel to
the centre of the rack structure to deposit
a load, and then it travels to ¾ the length
and height of the AS/RS to retrieve a load
AS/RS Throughput: Dual Command Cycle
54

pd
zy
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AS/RS Throughput: Dual Command Cycle
55

Rcs = number of single command cycles
performed per hour
Rcd = number of dual command cycles per
hour at a specified or assumed utilization
level
U = system utilization
Rc = total S/R cycle rate (cycles/hr)
Rt = the total number of transactions
performed per hour
AS/RS Throughput
56

The amount of time spent in performing
single command and dual command cycles
per hour
Rcs Tcs + Rcd Tcd = 60 U
The total hourly cycle rate
Rc = Rcs + Rcd
The total number of transactions
Rt = Rcs + 2Rcd
AS/RS Throughput
57

Each aisle of a five-aisle Automated Storage/Retrieval System
is to contain 40 storage compartments in the length direction
and eight compartments in the vertical direction. All storage
compartments will be the same size to accommodate
standard size pallets of dimension: x = 30 in and y = 40 in.
The height of a unit load z = 25 in. Using the allowances a = 6
in, b = 8 in, and c = 10 in, determine:
¤ How many unit loads can be stored in the AS/RS
¤ The width, length, and height of the AS/RS
Consider that an S/R machine is used for each aisle. Suppose
horizontal and vertical speeds of the S/R machine are 250
ft/min and 50 ft/min, respectively. The S/R machine requires
18 sec to accomplish a pick-and-deposit operation. Find:
¤ The single command and dual command cycle times per aisle
¤ Throughput for the aisle under the assumptions that storage
system utilization = 90% and the numbers of single command
and dual command cycles are equal.
Example
58

59

Horizontal
¤ Operation is similar to overhead conveyor system
used in dry cleaning establishments
¤ Items are stored in bins suspended from the
conveyor
¤ Lengths range between 3 m and 30 m
¤ Horizontal is most common type
Vertical
¤ Operates around a vertical conveyor loop
¤ Less floor space required, but overhead room
must be provided
Carousel Storage Systems
60

61

62

Horizontal Carousel Storage System
Manually operated
horizontal carousel
storage system
63

Horizontal Carousel Storage Systems
64

Vertical Carousel Storage Systems
Vertical Carousels
consist of a series of
horizontal trays on a
vertical carousel.
Vertical carousels are
most effective when
floor space is at a
minimum and there is
ample overhead
clearance.
65

Vertical Carousel Storage Systems
66

Storage and retrieval operations
¤ Order picking
Transport and accumulation
¤ Progressive assembly with assembly stations
located around carousel
Work-in-process
¤ WIP applications in electronics industry are
common
Unique applications
¤ Example: time testing of electrical products
Carousel Applications
67

C = circumference of oval conveyor track
L = the length of the track oval
W = the width of the track oval
nb = the number of bins hanging vertically
from each carrier
nc = the number of carriers around the
periphery of the rail
sc = the center-to-center spacing of carriers
along the oval track/carrier spacing
(m/carrier)
Storage Capacity
68

C = 2 (L – W) + π W
Total number of bins = nc nb
sc nc = C
Storage Capacity
69

Assumptions
¤ Only single command cycles are performed: a bin
is accessed in the carousel either to put items
into storage or to retrieve one or more items from
storage
¤ The carousel operates with a constant speed vc:
acceleration and deceleration effects are ignored
¤ Random storage is assumed: that is, any location
around the carousel is equally likely to be
selected for an S/R transaction
¤ The carousel can move in either direction
Throughput Analysis
70

Tc = S/R cycle time (min)
C = carousel circumference (m)
vc = carousel velocity (m/min)
Tpd = the average time required to pick or
deposit items each cycle by the operator
at the load/unload station (min)
¤ The number of transactions accomplished per hour is the same
as the number of cycles
Throughput Analysis
71

c
ct
pd
c
c
T
U
RR
T
v
C
T
60
4
==
+=
Throughput Analysis
72

Suatu sistem penyimpanan carousel tunggal
memiliki suatu rel loop oval dengan ukuran
panjang 40 kaki dan lebar 3 kaki. Delapan
kereta pembawa terpasang dengan jarak sama
sepanjang rel oval. Ada 6 kotak tergantung pada
masing-masing pembawa. Setiap kotak
berkapasitas volumetric 1.25 m2
. Kecepatan
carousel = 80 kaki/menit. Waktu ambil/simpan
rata-rata = 25 detik. Tentukan:
¤ Kapasitas volumetric sistem penyimpanan ini
¤ Laju pengambilan sistem penyimpanan per jam
Example
73

AUTOMATED DATA CAPTURE
74

Also known as automatic identification
and data capture (AIDC)
It refers to the technologies that provide
direct entry of data into a computer or
other microprocessor controlled system
without using a keyboard.
These technologies require no human
involvement in the data capture and entry
process.
Automated Data Capture
75

Collect data in material handling and manufacturing
applications.
¤ In material handling, the applications include shipping and
receiving, storage, sortation, order picking. and kitting of
parts for assembly.
¤ In manufacturing, the applications include monitoring the
status of order processing, work-in-process, machine
utilization, worker attendance, and other measures of
factory operations and performance.
ADC has many important applications outside the
factory; including retail sales and inventory control.
warehousing and distribution center operations, mail
and parcel handling, patient identification in hospitals,
check processing in banks, and security systems.
Automated Data Capture
76

The automatic identification technologies
consist of three principal components,
Encoded. A code is a set of symbols or signals (usually)
representing alphanumeric characters. When data are encoded, the
characters are translated into a machine-readable code.
Machine reader or scanner. This device reads the
encoded data, converting them to alternative form, usually an electrical
analog signal.
Decoder. This component transforms the electrical signal into
digital data and finally back into the original alphanumeric characters.
Automatic Identification Technologies
77

ADC technologies can be divided into the
following six categories :
¤ Optical
¤ Magnetic
¤ Electromagnetic
¤ Smart Card
¤ Touch Techniques
¤ Biometric
ADC Technologies Categories
78

1. bar codes
2. radio frequency methods,
3. magnetic stripe,
4. optical character recognition, and
5. machine vision,
ADC Technologies most widely used
79

ADC Technologies
80

Readable code
The symbol consists of bars and spaces
of varying width or height;
Two basic types:
¤ Linear (one-dimensional), in which the encoded
data are read using a linear sweep of the scanner,
¤ Two-dimensional, in which the encoded data must
be read in both directions.Bar code scanner/reader
Bar code readers and printers
Barcode Technology
81

Barcode Technology
82

Advantages:
¤ Data entry is faster,
¤ Data input is more accurate,
¤ Data search is more integrity,
¤ Reduce Costs,
¤ Management Performance Improvement
Barcode Technology
83

Barcode Technology
84

Barcode Technology: LINEAR BARCODE (1 D)
85

Universal product code
¤ A numeric barcode
¤ Has a fixed length about 12 digits. Six digits to
identify the manufacturer, five digits to identify
the product, and the final digit is a check
character.
¤ UPC is used for retail product labelling.
¤ This symbol is made to ease of authenticity of
a product. UPC numbers must be registered
or registered with the Uniform Code Council.
86

Code 39
¤ An alphanumeric barcode (full ASCII).
¤ Has a varied length.
¤ Code 39 is used for product identification,
inventory control, and automation of the
check-out procedure. And also for asset
tracking and identity recognition.
87

Code 128
¤ An alphanumeric barcode (full ASCII).
¤ Has a varied length with high density.
¤ Code 128 is used for shipping and
warehouse management.
88

89

Advantage:
¤ Has higher capacity to store much greater
amounts of data at higher area densities. It has
better speed, accuracy of data and the number of
characters that can be accommodated. With
capacity up to 2000 characters, 2D Barcode is
enough to encode some text and compressed
image files.
¤ 2D Barcode can be printed in smaller space.
• Stacked Bar Codes
• Matrix Symbologies.
¤ A digital camera and an application can be
implemented as devices to scan and read 2D
Barcode
Barcode Technology: Two-dimensional
90

91

92

BARCODE SCANNER / READERS
¤ Barcode reader/scanner adalah perangkat
untuk membaca kode-kode garis visual
barcode. Hanya dengan menyapukan segaris
sinar laser, ia dengan cepat membaca
fragmen terang gelap pada barcode yang
tercetak di kertas dengan sangat cepat dan
akurat. Pada perkembangan selanjutnya,
sinar laser yang dipancarkan tidak hanya
sebentuk garis saja tapi berupa kombinasi
pola yang rumit sehingga mampu membaca
barcode dari sudut manapun.
Barcode Technology
93

BARCODE PRINTERS
¤ Simbol barcode bisa dihasilkan dengan
beragam cara mulai penandaan langsung
(direct marking) atau mencetak dengan ink jet
atau mencetak simbol barcode kedalam label
terpisah (separate label). Printer barcode
adalah sebuah peralatan komputer yang
digunakan untuk mencetak label barcode
maupun kartu penanda (tag). Sekali label
barcode dicetak maka akan dapat ditempel
pada obyek fisik seperti barang-barang retail
dan perkapalan.
Barcode Technology
94

Radio frequency identification
Magnetic stripes
Optical character recognition
Machine vision
Other ADC Technologies
95

metode identifikasi dengan menggunakan
sarana yang disebut label RFID atau
transponder untuk menyimpan dan
mengambil data jarak jauh
96

terdiri dari dua bagian:
¤ RFID reader
• Membaca kode-kode pada tag
¤ RFID tag atau label
• sebuah benda yang bisa dipasang atau
dimasukkan di dalam sebuah produk, hewan atau
bahkan manusia dengan tujuan untuk identifikasi
menggunakan gelombang radio
97

98

Dilampirkan pada produk yang biasanya
digunakan untuk mengidentifikasi dalam
aplikasi gudang dan persediaan
Film plastik yang tipis yang mengandung
partikel magnetic kecil yang dapat
digunakan untuk mengkode data menjadi
bentuk film.
Pita warna hitam
Dapat dibaca ataupun ditulis (R/W)
Magnetic stripes
100

Magnetic stripes
101

Sistem komputer yang dapat membaca huruf, baik yang
berasal dari pencetak maupun tulisan tangan
Metoda pembacaan data oleh scanner optik dan
menterjemahkan data tersebut ke dalam bentuk data biner
yang dapat dibaca oleh komputer.
Mengubah hard copy menjadi softcopy
Pencocokan pola
Dua metode:
¤ Matric matching (pencocokan pola karakter dengan data base)
¤ Feture Extruction (mendeteksi karakter dari ruang kosong, garis
diagonal, bentuk yang berpotongan, dan perpotogan garis)
Memudahkan penyortiran surat di kantor pos, pemasukan
data di perpustakaan, mendeteksi tanda tangan, sidik jari
scaner
Pola gambar  kode huruf-huruf berupa angka
Optical Character Recognition
102

103

Data capture merupakan proses konversi suatu
dokumen (hardcopy) menjadi suatu file gambar
(BMP).
Preprocessing merupakan suatu proses untuk
menghilangkan bagian-bagian yang tidak
diperlukan pada gambar input untuk proses
selanjutnya. contoh preprocessing adalah noise
filtering.
Segmentasi adalah proses memisahkan area
pengamatan (region) pada tiap karakter yg akan
dideteksi.
Normalization adalah proses merubah dimensi
region tiap karakter dan ketebalan karakter.
Dalam OCR algoritma yang digunakan pada
proses ini adalah algoritma scaling dan thinning.
Feature Extraction adalah proses untuk
mengambil ciri-ciri tertentu dari karakter yang
diamati.
Recognition merupakan proses untuk
mengenali karakter yang diamati dengan cara
membandingkan ciri-ciri karakter yang diperoleh
dengan ciri-ciri karakter yang ada pada
database.
Postprocessing pada umumnya adalah proses
yang dilakukan pada tahap ini adalah proses
koreksi ejaan sesuai dengan bahasa yang
digunakan.
104

105

Definisi
¤ Sensing of vision data and its interpretation by
a computer
Terdiri atas
¤ Camera and digitizing hardware
¤ Digital computer
¤ Hardware and software necessary to interface
them (preprocessor)
Machine Vision
106

Fungsi di dalam Operasi MV
¤ Terdiri daripada 3 fungsi dalam machine
vision
• Fungsi I: Sensing and digitizing image data
• Fungsi II: Image processing and analysis
• Fungsi III: Application
¤ Setiap fungsi mempunyai kepentingan
masing-masing dalam satu sistem machine
vision
Machine Vision
107

Machine Vision
108

Pengenalan Fungsi I
¤ Sensing and digitizing image data
• Hardware
 Camera
 Lighting
 Frame Grabber
• Teknik dan Aplikasi
 Signal conversion
 Image Storage/Frame grabber
 Lighting
¤ Memerlukan teknik pencahayaan (lighting) yg
istimewa
¤ Frames mengandungi pictures elements/ pixels
¤ Image bagi setiap frame disimpan dan dibawa ke
Fungsi ke II
Machine Vision
109

Pengenalan Fungsi II
¤ Image Processing and Analysis
• Hardware
 Computer (processor)
 Monitor/keyboard
 Stored programs/algorithm
 Data reduction
 Segmentation
 Object recognition
¤ fungsi II, sistem machine vision harus dilatih
Machine Vision
110

Pengenalan Fungsi III
¤ Application
• Hardware
 Robot controller
 Inspection
 Identification
 Visual navigation
Machine Vision
111

Techniqu
e
Time
to
Enter
Error
Rate
Equipment
Cost
Advantage/
(disadvantages)
Manual
Entry
Slow High Low Low initial cost
Requires human operator
(slow speed)
(High error rate)
Bar code :
1 D
Mediu
m
Low Low High speed
Good flexibility
(low data density)
Bar code :
2 D
Mediu
m
Low High High speed
High data density
(high equipment cost)
Radio
Frequency
Fast Low High Label need not be visible
(expensive labeling)
Perbandingan teknik ADC
112

Techniqu
e
Time
to
Enter
Error
Rate
Equipment
Cost
Advantage/
(disadvantages)
Magnetic
Stripe
Mediu
m
Low Medium Much data can be encode
Data can be changed
(vulnerable to magnetic
field)
(Contact required to
reading)
OCR Mediu
m
Mediu
m
Medium Can be read by humans
(low data density)
(high error rate)
Machine
Vision
Application
Fast *** Very high Equipment expensive
(not suited to general)
ADC
Perbandingan teknik ADC
113

It’s end of slides…It’s end of slides…
…… Any question ?Any question ?

04 material handling - part4

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04 material handling - part4