Smart Bag
A Personal Belonging Reminder System
ENGR 103 Section A-065 Group 01
Engineering Design Lab III
Fall 2013-14
Group Members:
Sida Liu
Nooraldean Aldabdoub
Nicholas Maffei
Roland Ngaba
1
Table of Contents
Executive Summary ................................................................................................... 3
Proble m State ment ..................................................................................................... 4
Objective Statement
................................................................................................. 5
Evaluation of Alte rnatives ......................................................................................... 6
Design ........................................................................................................................ 10
The Constraints of the Designs ................................................................................... 14
Standard of HF-RFID technology .............................................................................. 15
Analys is of Potential Hazard ..................................................................................... 15
Materials Used in Design ......................................................................................... 16
Cost Analysis of Prototype ...................................................................................... 18
Cost of Production ................................................................................................... 18
Marketing ................................................................................................................. 20
Conclusion ................................................................................................................ 21
References ................................................................................................................. 23
Appendix ................................................................................................................... 24
Gantt Chart .............................................................................................................. 24
Rank Ordering .......................................................................................................... 24
Weighting Factors..................................................................................................... 25
The Smart Bag ......................................................................................................... 26
2
List of Figures
Figure 1 Smart Bag Mk. I Circuit Diagram ................................................................... 12
Figure 2 Smart Bag Mk. II Circuit Diagram ................................................................ 13
Figure 3 The Smart Bag ........................................................................................... 26
List of Tables
Table 1 Decision Matrix ......................................................................................... 6
Table 2 Gantt Chart ............................................................................................. 24
Table 3 Rank Ordering ........................................................................................ 24
Table 4 Weighting Factors .................................................................................. 25
3
Executive Summary
Many people have a lot of things to keep track of during the day. Students, for
example, have to make sure they have particular books with them for different
classes. Lawyers need to have different client files with them at different times.
In
both of these cases, not having the required items at the correct times can result in
many problems. The Smart Bag’s goal is to provide a means of easily keeping track
of which items are needed at what time and whether you currently have them with
you or not. Using RFID scanners and tags, the Smart Bag can determine which items
are in the bag and which are not. An integrated control board interfaces with a
smartphone via a cable with an adapter to allow powering the device and scanning for
tags.
Using the free Smart Bag app for Android and iOS devices, the consumer can
program in which tags are attached to what items and which items are necessary at
what times.
The app will alert them when they need to pick up a new item and the
current status of their backpack can be checked by attaching the smartphone to the
backpack.
Problem Statement
4
The memories of human beings are not perfect. Almost everybody has experiences of
leaving personal belongings behind, such as keys, wallets, books, or medications.
Therefore, people need a system to remind them what they can leave behind and what
they should bring. The problem is that people don’t always remember what they
should bring and how to check whether they have everything in their bags. According
to the statistics from Hermann Ebbinghaus, the average person can only remember 40%
of what they learned 20 minutes ago. This means even if one finds out that he needs to
bring an object with him 20 minutes later, without any reminding mechanism, there is
only a 40% chance that he will remember to bring this object with him. If this object
is a textbook then he will go to class and probably waste the whole time because he
forget his textbook. If something like the house keys were forgotten, one may be
locked out of their house for hours before getting help from others. If some essential
medication was forgotten, a life could be threatened or even lost simply due to
forgetfulness. The consequences of this problem can be as little as a waste of couple
hours or a matter of life and death. Therefore, people need a system to remind them
what they leave behind and what they should bring, especially for people who tend to
forget things often and people who always need to bring important belongings with
them.
5
Objective Statement
The objective of this project is to design a device that allows the consumer to
know both what they need and whether they currently have it in their bag, ready to go.
This device would need to be easy to use, affordable, durable, and aesthetically
pleasing in both look and feel. The weight of the added material should be kept at a
minimum so as to keep the added strain on the user to a minimum. Also, minimal
space should be consumed by the added components. Cost of materials will be kept as
low as possible through researching the correct technologies to use in the design.
However, effectiveness of the product will not be sacrificed for cost as long as the
difference in function is not large. Market research will be performed to determine the
correct audience to market this product to and for future improvements.
6
Evaluation of Alternatives
After performing rank ordering1 , durability was determined as the most important
factor of the evaluation and ease of use follows as the second most important. Cost is
considered less important than the other two factors and aesthetics is considered the
least important aspect in the evaluation. Then each criterion is given a specific
weighing factor corresponding to its importance. Later, each alternative is evaluated
and gets a single score range from one to ten for each criterion. Finally, The Decision
Matrix (Table 1) was generated to show the results of comparing our designs against
the other alternatives.
Table 1- Decision Matrix
Goals
Durability
Ease of use
Cost
Aesthetics
Weighting Factors
Design Alternatives
90
80
40
30
Total
1. Reminder
6/540
3/240
9/360
4/120
1260
2. Smart Bag Mk.I
9/810
8/640
7/280
9/270
2000
3. Smart Bag Mk.II
8/720
9/720
6/240
9/270
1950
4. Smartphone Apps
7/630
5/400
10/400
7/210
1640
In the Decision Matrix, the scores from the polling are multiplied by the weighing
factors to generate a weighted score. Then the four weighted scores of each alternative
are summed to the total weighted score for this alternative.
Before any analysis upon the results from the decision matrix, a brief description
of each alternative should be introduced.
7
The first alternative is a reminder, namely a notebook or a sheet of printed
schedule on a paper, which can remind a person what to bring each day.
The second alternative is Smart Bag Mk. I. It is a small tag containing a passive
Radio Frequency Identification (RFID) circuit inside which can be detected by a
scanner transmitting out radio waves with specific frequencies. The tag can be
attached to a specific item and the scanner is embedded into the bag. The scanner will
be able to detect the tag when it is connected to a smartphone. If the scanner picks up
the signal from the tag, then the item attached by the tag is known to be inside the
bag.
The third alternative is Smart Bag Mk. II, which acts similar to the Smart Bag Mk.
I. The only difference is that it applies the Battery Assisted Passive Radio Frequency
Identification (BAP-RFID) technology instead. This means each tag will have a
circuit with a small battery that can transmit back a stronger signal when it is
activated by the scanner.
The last alternative is a simple smartphone reminder app.
This uses your smart
phone’s native apps to set up reminders or a notebook computer to remind you when
you need items for classes or meetings.
The first evaluation factor is durability. Smart Bag Mk. I gets a score of 9 because
it doesn't require any batteries to operate and doesn't need to replace any part if
operated properly by the user. The Smart Bag Mk. II gets a score of 8, slightly lower
than the Smart Bag Mk. I because each tag in the Smart Bag Mk. II needs a small
8
battery to operate. However, the battery can last years since the device doesn't draw
power from it most of the time. The smartphone app gets a score of 7 because upon
several tests, the smartphone doesn't send notice when it is silenced or in vibration
mode and the battery of a smartphone lasts only hours. Lastly, the reminder gets a
score of 6 because the reminder itself can be left behind or forgotten by the owner.
The second criterion is ease of use. The Smart Bag Mk. II gets a score of 9
because it only takes seconds to check every single tag inside the bag and find out
what is left behind. The Smart Bag Mk. I gets a score of 8, because the signal
transmitted back by the tag is weaker and easier to be blocked by metal or water,
causing the scanner to miss that an item is, in fact, in the bag. The smartphone app
gets a score of 5 because it takes too much time and effort to set up notices every day
for each meeting or class. The reminder gets a score of 3 because it is a tedious job to
write down everything one needs to use and requires the user to check the notebook
against everything in the bag to make sure they have it.
The third criteria is cost, which in the case of the smartphone app, costs nothing
extra if you already have a smart phone, so it gets a score of 10.
A notebook only
costs several dollars and can last months, thus it gets a score of 9. The Smart Bag Mk.
I may cost more, but can be used continuously without recharging or replacing.
Therefore it gets a score of 7.
Lastly, the Smart Bag Mk. II costs most and may need
to replace the tags or batteries after a couple years, thus it gets a score of 6.
9
The forth criteria is aesthetics. Both the Smart Bag Mk. I and the Smart Bag Mk.
II get a score of 10 because they are light-weight and do not affect the aesthetics of
the original bag.
A smartphone app gets a score of 7 because you have to bring a
smartphone whenever you need to check all the belongings in the bag.
The reminder
gets a score of 4 because it adds more weight to the bag and it takes additional space.
Overall, the Smart Bag Mk. I gets a total score of 2000 and the Smart Bag Mk.II
gets a total score of 1950. They are considered the best alternatives after the
evaluation process. The smartphone app gets a total score of 1640 and the reminder
gets a score of 1260, neither of which is a match for the Smart Bag Mk. I or Mk.II.
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Design
Before introducing our designs, let's have a look at the question:
What is Radio Frequency Identification (RFID) technology?
RFID is a wireless, radio-frequency labeling method. Objects are given a
particular identification, stored on a tag, which can be read at range by an RFID
reader. Usually, RFID tags require very little space and energy, and can be stored in
other objects without causing a problem. Typical range is less than three meters, but
with more power, can be extended to hundreds of meters. This system can be used for
many different things, most commonly for inventory management, assembly line
tracking, or even tagging livestock. Commerce is a growing market for RFID
technology, as some credit cards now have embedded RFID tags for checking out at
registers.
However, there is more than one RFID standard available and each RFID
standard has its own strengths and weakness. Therefore, by comparing different RFID
standards, the best RFID standard can be determined for this project.
When categorized by frequency, there are three major types of RFID standards;
the Low-Frequency RFID (LF-RFID), the High-Frequency RFID (HF-RFID) and the
Ultra-High-Frequency RFID (UHF-RFID). First, the LF-RFID tags have the best
penetration strength and LF-RFID tags have the lowest cost. However, typically
LF-RFID tags only have a range of 4 inches. Second, the HF-RFID tags have strong
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penetration strength, a reasonable range of about 1 to 3 meters and each tag only costs
a couple of dollars. Finally, the UHF-RFID tags have the best range among the three.
However, UHF-RFID tags have low penetration strength, so little, that a bottle of
water or a piece of metal can block almost all of the signals.
Also each UHF-RFID
tag costs more than $50. Overall, the best one for the project is the HF-RFID tag.
When categorized by power source, there are also three major types of RFID
standards broken into to categories, namely Passive RFID systems and Battery
Assisted Passive RFID (BAP-RFID) systems. First, the Passive RFID system does not
require a battery to run the tags. Therefore, it costs the least to maintain and can be
made into flexible shapes such as a plastic sticker. However, it can only send out a
weak signal which is difficult for the scanner to pick up. Second, the BAP-RFID
system has tags powered by a watch battery and the tags only draw power from the
battery to transmit out a signal when it is activated by the scanner. Therefore, it will
have a better range and penetration strength. Lastly, the Active RFID system has a tag
that is constantly powered by a battery so that it can be more sensitive and can send
out strong signals to the scanner. However, it needs a large battery and the battery
usually dies in a matter of days. Overall, either the Passive RFID system or the
BAP-RFID system can be adapted for the Smart Bag project.
With the analysis on which type of RFID is suitable for this project, either
Passive HF-RFID or the BAP-HF-RFID should work well. Without building a
prototype for both options, there is no way to find out which one of them is better.
12
Therefore, our project has two prototypes, namely the Smart Bag Mk. I, utilizing
HF-RFID and the Smart Bag Mk. II, utilizing BAP-HF-RFID.
Figure 1
The Smart Bag Mk. I Circuit Diagram (Figure 1) shows the blueprint of the
circuit design for the Smart Bag Mk. I. The system contains two major components,
the RFID Scanner Unit and the RFID Tag Unit. The RFID Scanner unit is embedded
into the bag or backpack with a cable that can be used to connect a smartphone or
tablet. The RFID Tag Unit is attached on a specific item as a tracker. When a
smartphone or tablet is connected to the scanner control unit, the scanner control unit
13
sends a specific signal that can activate a specific tag to the RF choke. The RF choke
converts the digital signal from the scanner control unit to a sine wave signal so that it
can be broadcasted into the air as radio. If the tag is inside the bag, its antenna will
pick up the signal. Then the RFID Tag will convert this wave signal to a different
electric signal with its identification information embedded. This electric signal will
be transmitted by the antenna of the RFID Tag Unit and the RFID Scanner Unit will
pick up the signal and decode the identification information embedded. Finally, the
scanner control unit will send confirmation that this item is in the bag to the
smartphone or tablet and start a scan on the next tag. However, if the tag is not inside
the bag, there will be no signal picked up by the scanner unit and the scanner control
unit will deny that this item is in the bag and send this information to the smartphone
or tablet.
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Figure 2
Smart Bag Mk. II circuit diagram (Figure 2) shows the blueprint of the circuit
design for the Smart Bag Mk. II. It uses almost the same mechanism as the Smart Bag
Mk. I. The only difference is that when a tag picks up the activation signal from the
scanner unit, it draws power from the small battery and uses that power to transmit
out the radio with its identification embedded
The Constraints of the Designs
One factor that needs to be kept to a minimum is the added weight to the
backpack that is chosen. Most likely, this will not be a problem, as the RFID tags
and scanners should be very light weight and take little room. This also means that
the available space in the backpack should not be adversely affected by the added
RFID technology.
Another factor to keep in mind is the power draw we pull from the
smart phone. Most smart phones have a limit on how much power can be utilized by
an accessory, so the device will need to pull less than that amount.
One important difference between the two versions of the Smart Bag system
when looking at constraints is that the Mk. II requires batteries for the tags to
work. This greatly increases the overall weight of each of the tags and will need to
be taken into account when considering the MK II as a viable option.
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Standard of HF-RFID technology
1. ISO/IEC 14443 Identification cards -- Contactless Integrated Circuit Cards -Proximity Card
The frequency of the radio used for communication is set as 13.56 MHz.
This standard also specifies the data transmission protocol between the HF-RFID
tag and the HF-RFID scanner. There are several techniques which can be applied
to avoid interference between individual HF-RFID tags, thus the HF RFID
reader only reads HF-RFID tags one by one.
2.
MIFARE
This is the standard to manufacture HF-RFID readers and HF-RFID tags based on
the ISO/IEC 14443. A majority of the manufacturers on the market use this standard
to manufacture the HF-RFID reader and HF RFID tags.
Analysis of Potential Hazard

Although the chance is very small, the radio transmitted by the Smart Bag
system may interfere with some sensitive electronics. However, the frequency
used in this system (13.56Mhz) is very different from the frequency used for cell
phones (800Mhz-1900Mhz) or wifi devices (2.4Ghz or 5.0Ghz). Therefore, the
Smart Bag system is highly unlikely interfere with most electronics.
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
The Smart Bag system contains small parts. The Smart Bag system should be
kept away from children at all times. It can cause seriously injures or even
fatalities when swallowed by children.

Some parts of the Smart Bat system may contain materials that are known to the
state of California to cause cancer.

Connecting this system to unsupported smartphones or other devices may burn
down the system and cause serious injuries or even fatalities.
Materials Used in Design
In the Smart Bag Mk. I

The antenna of the HF RFID scanner is made of copper wires because copper is
flexible and has great electric conductivity.

The circuit board of the scanner will be a multi- layer printed circuit board which
can reduce the size and weight of the scanner unit. The board is made of plastics
and copper.

There will be a plastic box used to enclose the circuit board.

There will be three different types of HF RFID tags:
o
A tag for key chains
Hard plastics with a circuit board embedded.
o
A sticker tag for smooth surfaces
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Flexible plastics with a circuit board embedded inside.
o
A card tag for wallets
Hard card-shape plastics with a circuit board embedded.
Smart Bag Mk. II

The antenna of the HF RFID scanner is made of copper wires because copper is
flexible and have great electric conductivity.

The circuit board of the scanner will be a multi- layer printed circuit board which
can reduce the size and weight of the scanner unit. The board is made of plastics
and copper.

There will be a plastic box used to enclose the circuit board.

There will be three different types of HF RFID tags:
o
A tag for key chains
Small hard plastics with a circuit board and a battery embedded inside.
o
A sticker tag for smooth surfaces
Hard plastics with a circuit board and a battery embedded.
o
A card tag for wallets
Hard card-shape plastics with a circuit board and a battery embedded
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Cost Analysis of Prototype
Smart Bag Mk. I
Each tag will cost around $0.40 for the RFID tag and the material it is
attached to. The RFID reader will cost $35 and be attached to an integrated
circuit board design, costing $10 per board and cables. A backpack bought from
Wal-Mart or Target may cost about $50. One backpack along with 10 RFID tags
and 2 RFID readers will cost roughly $120.
Smart Bag Mk. II
Each tag will cost around $3.00 for each RFID tag and the material and
battery it is attached to. The RFID reader will cost $35 and be attached to an
integrated circuit board design, costing $10 per board and cable. The backpack
from Wal-Mart or Target may cost about $50. With a setup of 10 RFID tags and 2
RFID readers and one backpack from Wal-Mart, the total cost of this prototype
adds up to about $170.
Cost of Production
In-House Production
In-house production will involve producing the circuit boards for the RFID
scanners, as well as integrating the boards into the backpack. Equipment to print
the boards will need to be purchased, as well as the space necessary to generate
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the number of boards required for production.
A small assembly workshop
would need to be constructed to integrate the RFID boards into the backpacks and
package the product to be sold. Roughly, it would cost more than $1 million to
build the production line and an extra $2 million to build the facility which holds
the production line. To maintain full productivity, the production line may need at
least 20 workers. According to the average wage of workers in the U.S.A, labor
will add up to $1 million. Even without adding tax into the cost, this facility will
cost about $3 million to build and $1 million to keep running. Even with a profit
margin of 15%, it will not make any profit unless total sales reach 8 million
dollars per year.
Outsourcing the Production
Outsourcing the production of the boards would increase average variable
cost slightly because of the tariff and the cost of shipping, but reduces the average
fixed cost vastly, making the average total cost stay relatively low. However, if
the sales reach more than 8 million dollars per year, outsourcing the production
can be costly.
To be safer, with the total sale under $10 million, the production of the Smart
Bag system should be outsourced. However, if sales reach $10 million and the
cost of production in the U.S. does not change much, then in-house production
will be a better choice.
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Marketing
The Smart Bag will be marketed towards students and others who require several
different items for various activities during the day, or who do not want to
accidentally leave an item somewhere.
For a student this may mean textbooks,
notebooks, and papers for particular classes each day. For others, it could be used to
ensure that important business documents or folders are available at meetings with
clients or during conferences.
It could even be used by parents to keep track of their
child's belongings after going on a class trip, or to ensure you bring everything of
importance home after a vacation away from home.
Marketing will begin with students in high school and college by selling the
product at college campuses and high school stores. A web site will also be available
from which the smart bag will be sold. Commercials will be run during prime time
local and eventually network television to advertise the utility of the Smart Bag for
students, parents, and businessmen alike. Ad space will also be bought from
YouTube to run during videos. The commercials, as well as the website will attempt
to show that the Smart bag is both a cool and useful piece of technology and can be
used in many different ways. Eventually, agreements will be made with large
commercial retail stores to sell the Smart Bag on their floor space as normal items.
Selling the Smart Bag in school stores to start with should incur very little
cost. Design and maintenance of the website should cost roughly $15,000 , with a
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$2,000 a year cost after that, based on expected network traffic.
A prime time local
Commercial time costs around $10,000 per 30 second ad, while a Network
commercial costs around $100,000. Buying in bulk should reduce these costs. Ad
space for 1000 ads can be bought on YouTube for $60. Contracts can be obtained
with retailers by setting wholesale prices and meeting with retailer agents to show
them the product.
The Smart Bag system will retail for $149.99.
Conclusion
The Smart Bag is a new and innovative way to keep track of all the things you
require during the day. It can be useful for anyone in any number of professions or
circumstances and can certainly save you from the situation of being without what
you need when you need it most. Some future design improvements include stronger
tag signals, so that items buried deeply in the backpack or wrapped in a thick layer are
not accidentally listed as missing.
Also, including more tags in the product as they
can be created for less would be a great improvement.
As RFID technology develops, the price and size of tags and readers will
decrease, allowing the product to cost even less.
As a future design, the Smart Bag
System could be integrated into many different types of containers, such as briefcases,
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luggage suitcases, or even cars.
This would allow for even more different uses,
where a backpack would be sub-optimal to use.
Alternate versions of tags, such as
tagged paperclips could also be a possible improvement in the future.
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References
Sen, Dipankar; Sen, Prosenjit; Das, Anand M. (2009),RFID For Energy and Utility
Industries, PennWell, ISBN 978-1-59370-105-5, pp. 1-48'
Weis, Stephen A. (2007), RFID (Radio Frequency Identification): Principles and
Applications, MIT CSAIL
ISO/IEC 14443-1:2008 Identification cards -- Contactless integrated circuit cards -Proximity cards -- Part 1: Physical characteristics
ISO/IEC 14443-2:2010 Identification cards -- Contactless integrated circuit cards -Proximity cards -- Part 2: Radio frequency power and signal interface
ISO/IEC 14443-3:2011 Identification cards -- Contactless integrated circuit cards -Proximity cards -- Part 3: Initialization and anti-collision
ISO/IEC 14443-4:2008 Identification cards -- Contactless integrated circuit cards -Proximity cards -- Part 4: Transmission protocol
"MIFARE SmartCard IC's." Mifare.net :: MIFARE SmartCard IC's. NXP
Semiconductors, 2 Feb. 2008. Web. 02 Dec. 2013.
Kjpcb 旗舰店. "Cost of Outsourcing Production." Interview by SIDA LIU. Oct. 10th
2013
Kjpcb 旗舰店. "Cost of Prototype Production." Interview by SIDA LIU. Oct. 15th
2013
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Appendix
1
Week
2
3
4
5
6
7
8
9
10
11
12
Needs Assessment
Problem Formulation
Alternative Design
Polling
Materials&Production
Cost analysis
Marketing
Report writting
Presentation preparation
Rehearsal of Presentation
Table 2 Gantt Chart
cost
aesthetic
cost
aesthetic
ease of use (user friendly)
durability
ease of use
1
0
0.5
1
1
1
Table 3 Rank Ordering
durability
Total Score
0.5
0
1.5
0
0
0
0.5
2
0.5
2.5
25
WEIGHTING FACTORS
100
95
90
durability
CRITICAL
85
80
ease of use
75
70
65
60
IMPORTANT
55
50
45
40
35
OPTIONAL
30
25
20
cost
aesthetics
15
10
5
0
Table 4 Weighting Factors
26
Figure 3