1. i
FACULTY OF ENGINEERING AND BUILD ENVIRONMENT
DEPARTMENT OF MECHANICAL AND MATERIAL ENGINEERING
KKKP 4274 Product Design
4th
Year Semester I 2011/2012
Product Design Project Final Report :
Arthritis Hand-Aids
Design Team 6
1. CHAN KIEN HO ( A125070 )
2. HOW YONG CHIAN ( A123700 )
3. MOHAMAD MUSTAKIEM BIN MOHD ZAKI ( A123754 )
4. MUHAMMAD IDHAM BIN SABTU ( A124520 )
5. NURUL NUUR ASHIEKEEN BINTI ZULKIFLEE ( A126457 )
Lecturer : PROF. MADYA DR. DZURAIDAH ABD. WAHAB
Supervisor : DR. RIZAUDDIN RAMLI
Due Date : 23 December 2011
2. i
Contents
CHAPTERS PAGES
I. Contents i
II. Acknowledgement ii
III. Executive Summary iii
1.0 Gantt Chart 1
2.0 Brainstorming 1
3.0 Problem Statement 2
4.0 Design Objectives 2
5.0 Analysis Of Survey Results 3
6.0 Quality Function Deployment (QFD) 4
6.1 House Of Quality 7
7.0 Product Design Specification (PDS) 8
8.0 Functional Decomposition 10
9.0 Concept Generation 11
9.1 Morphological Chart 12
9.2 Concept Combination 14
10.0 Concept Evaluation 15
10.1 Pugh’s Concept Selection 16
10.2 Concept Comparison 17
11.0 Concept Selection 18
11.1 Weighted Decision Matrix 19
11.2 Final Concept 19
12.0 Embodiment Design 20
12.1 Product Architecture 21
12.2 Failure Mode & Effect Analysis (FMEA) 22
12.3 Design For X (DfX) 23
13.0 Detailed Design 31
13.1 Exploded View And Bill Of Material (BOM) 32
13.2 Engineering Analysis 33
14.0 Material And Costing 37
14.1 Material Selection 37
14.2 Cost Estimation 39
15.0 Conclusion 40
16.0 References 42
17.0 Appendix 43
3. ii
ACKNOWLEDGEMENT
First and foremost, it is grateful to have team members who are committed and devote a
lot of efforts to finish the project within the time given. Next, a special gratitude to our
lecturer, Prof. Madya Dr. Dzuraidah Abd. Wahab who is dedicated in teaching the
course KKKP4274 Product Design, willing to guide and help us to complete the project.
Besides, we would also like to thank to our supervisor, Dr. Rizauddin Ramli who has
spent his time to do meeting with us, providing us the valuable opinions and suggestions
to improve our project.
We feel very fortunate to be given this opportunity to conduct this task because
along doing this project, a lot of information and knowledge can be gains and very clear
visualize of theory that we learns in class that will apply at real industries. The
knowledge and experience are benefits to us when we entered the real works in future as
an engineer. This project we not considered as burden but it is learning process that
teaches us how to apply the knowledge, skills, interaction and communication to others
and a lot more.
Last but not least, thanks to friends and others that involved in this project for
giving their supports, helps and brainstorm to solve the problem we faced. All this co-
operation is greatly appreciated for completing this product design project.
4. iii
EXECUTIVE SUMMARY
In this project, we were re-designing the current arthritis tool in market so that the
product can be more reliable, high impact resistance, parts inter-changeability and
comfortable to use. 30 survey forms were distributed to the public who are facing the
arthritis problem. The survey was emphasized on difficulty level of daily activities and
the comments & suggestion for the new product. After analyze the survey result, we
determined the engineering characteristic rank order according to the customer’s
requirements in House of Quality. Higher activity diagram is the general information
about the functions that will performed by the product and functional modeling described
the detail function process. For concept generation, few alternatives for each part of
product were presented in graphical method and 15 concepts were chosen based on the
alternatives. 6 concepts left after concept evaluation by using Pugh’s method. The
advantages and disadvantages of each concept were listed and best concept was generated
through weighted decision matrix. The 4 general steps to construct the product
architecture are combined the functional diagram, modular chunks, relationship on
hierarchy components structure and incidental interaction. The parametric designs
include Failure Mode Effect Analysis for part function, detail drawing, dimension &
tolerance, assembly & exploded view and stress analysis in critical parts. Design for X
also has been included inside the report. The material selection by using CES 2005 and
cost estimated for product were the last section in project.
5. 1
1.0 GANTT CHART
Once the team member has been decided, we have planned and executed the activities
and tasks according to the gantt chart below.
2.0 BRAINSTORMING
In order to start the project of product design, all the team member shall sit together and
start brainstorming. Brainstorming is a group creativity technique to generate ideas where
all the member will give suggestions on what product shall be developed. Eventually, we
have decided to focus on Arthritis Multifunctional Tools where we name it as “Arthritis
Hand Aids”. There are several ideas being discussed as listed below and shown in
appendix A1 and A2.
i. Gym Equipment for Handicap
ii. GPS Holder at Motorbike
iii. Portable and Adjustable Chair
iv. Emergency Car Key Chian
v. Arthritis Multifunctional Tools
vi. Adjustable Allen Key
vii. Automatic Lamp
viii. Multifunctional Torch Light
Gantt Chart
Week 11/9 18/9 25/9 2/10 9/10 16/10 23/10 30/10 6/11 13/11 20/1127/11 4/12 11/12 18/12
Task w1 w2 w3 w4 w5 w6 w7 w8 break w9 w10 w11 w12 w13 w14
Brainstorming
( Ideas to develop new product)
Proposal Report 1
(problems, survey results, PDS, QFD)
Proposal report 2
(conceptual design , functions )
Embodiment design
( detail drawing, analysis, )
1 .
2 .
3 . Presentation ‐ brainstorming results
No.
Design Team Formation
4 . Conduct surveys
5 .
7 .
6 . Presentation ‐ proposal report 1
8 Presentation ‐ proposal report 2
9 .
10 . Compile Final Report
11 . Presentation ‐ final report
12 . Team meeting
6. 2
3.0 PROBLEM STATEMENT
Arthritis is a disease that causes pain and loss of movement of the joints. Arthritis
literally means inflammation of one or more joints. However, we would like to focus on
people with hand arthritis who having difficulties using their hands to perform daily
activities. Hand arthritis is specifically very painful and debilitating due to the fact that
hands have nineteen long bones and eight small bones that has several small joints in
between.
People with hand arthritis often find that pain, stiffness and fatigue cause
problems when performing simple task such as opening a door knob and a softdrink can,
using a screwdriver, carrying plastic bags with load during shopping. Therefore, we
would like to design a hand aids tool meanwhile integrate as many function as possible.
The hand aids tool is portable, light weight, easy to use and store. The product
will be given focus on the stress-strain analysis, to ensure it will not undergo deformation
and failure when certain amount of force being applied. The cost of product shall within
the range of RM30-RM50.
4.0 DESIGN OBJECTIVES
4.1 The objectives of designed product is stated as below:
i. To aids the people with hand arthritis to do a range of daily task, solving the
problem of using hand to grip, hold and apply force on something
ii. To develop a hand aids tool which is multifunctional and reliable
iii. To improve the current existing design based on the requirement of customers
7. 3
4.2 The objectives is clarified through the objective tree as below:
Figure 4.1 Objectives Tree
5.0 ANALYSIS OF SURVEY RESULTS
In order to identify the needs of customers, information is being gathered through
customer surveys. A total number of 30 questionnaire is distributed to people who are
suffering from hand pain or arthritis. Part of the survey is being conducted at Hospital
Serdang to obtain a better and accurate information. The questionnaire is shown in
appendix B1 to B4 Basically the questionnaire is divided into 4 sections where part 1 and
part 2 is to investigate the level of difficulty for the response to perform the listed
activities, then focus is given on these elements as to fulfill the customer needs. Whereas
part 3 is to collect the opinion of customer to determine the product features they desired.
Part 4 is to indicate the willingness of customer to purchase product. All the raw data is
summarized into a bar chart as shown in appendix B5 to B7. A mind mapping of survey
question also shown in appendix B8.
8. 4
6.0 QUALITY FUNCTION DEPLOYMENT (QFD)
Quality Function Deployment (QFD) is also known as House of Quality where the main
function we build this diagram in this product design to determine prioritize customer
demands and customer needs, spoken and unspoken, translating these needs into actions
and designs such as technical characteristics and specifications, and to build and deliver a
quality product or service, by focusing various functions toward achieving a common
goal of customer satisfaction for this arthritis tool.
Below are the steps to construct an efficient and accurate QFD. There are 11 steps
involved.
i. The Customer Requirement (Demanded Quality).
We need to identify who is our product’s customer and try to gather the information
from the particular group of people what is the requirement on the new designed
product. From the survey analysis, we only interpreted the result of survey’s
statements that get high customer’s vote to few important functions such as light
weight, clamp and clip tightly, adjustable for different size and task, easy to carry,
easy to put on, multiply the force efficiently and aesthetic.
ii. Regulatory Requirement.
Beside that the requirement that customer requested. We also document requirements
that are dictated by management or regulatory standards that the product must adhere
to. For example, Safety, comfortable used, anti corrosion and robust.
iii. Customer Weight/Important.
On a scale from 1 - 5, customers then rate the importance of each requirement. This
number will be used later in the relationship matrix. But on our QFD construction,
we try to analysis the scale based on the number of customer’s vote.
9. 5
iv. Competitive Analysis.
In this section, we also need the customers to judge or give the comments about our
new designed product with compare to the other competitors.
v. Quality Characteristic.
This can be called as “Voice of Engineer”. Few characteristics that we suggested in
order to improve the product quality and meet the customer needs. The
characteristics are No. of color, size, fatigue, toughness, hardness, environment effect,
physical appearance, cost and type of materials.
vi. Direction of Improvement.
Based on our logical thinking and decision, the movement of the each Quality
Characteristic was determined. For example, Size and Cost or the product must be
reduced and Fatigue and Toughness should be increased.
vii. Relationship Matrix.
The relationship matrix is where determines the relationship between Quality
Characteristic and Demanded Quality. Relationships can either be weak, moderate,
or strong. For example, The Weight has the moderate relationship with Size because
Type of Material has a great contribution into the product Weight. But, Size has a
strong relationship with Multiply the Force Efficiently because apply the same force
at different length will get the different torque.
viii. Organization Difficulty.
Rate the design attributes in terms of organizational difficulty. It is very possible that
some attributes are in direct conflict. In our decision, 0 represent easy to accomplish
and 10 represent extremely hard to implement. One of the targets that hard to achieve
or implement among the Quality Characteristic is Fatigue because it requires
expensive software like Autodesk Inventor for stress-strain analysis. Another than
that, plenty time also needed for the design engineer to get the optimum design.
10. 6
ix. Target Value for Quality Characteristic.
The target of the product for each descriptor is still in un-certainty because the
improvement for the features still needed and the mechanism for the adjustable
clamping function is still in un-known state. The target value will be determined
once the final design is coming out.
x. Correlation Matrix.
In this section, we examined how each of the Quality Characteristic impact to each
other. After that, we document strong negative relationships between technical
descriptors and work to eliminate physical contradictions. The number of color in the
product has no relationship with the environment effect. But they type of material
used will has strong effect to the manufacturing cost and conflict will occur between
this two characteristics. Then we need to observe the Rank Order to determine which
Characteristic is the most important among them.
xi. Absolute Importance and Rank Order.
The absolute important for each Quality Characteristic is the product between
Customer Important value and cell value in the Relationship Matrix. After that, we
determined the rank Order according Absolute Important. The higher Absolute
Important will get the priority compare to lower value.
11. 7
6.1 House of Quality
From the figure above, we can conclude that the priority of improvement should
be first given to size , second is fatigue, third is hardness and follow by toughness, type of
material, physical appearance, colours and hardness
Column 1 2 3 4 5 6 7 8 9
Direction of Improvement
▼ ▼ ▲ ▲ ▲ ▲ ▲ ▼ ▲
1 9 7.0 3.0 Light Weight Ο Ο Θ 4 2
2 2.3 1.0 Safety 2 3
3 9 7.0 3.0 Clamp and clip tightly Θ 4 2
4 9 11.6 5.0 Multiply the force efficiently Θ Ο Θ 3 2
5 9 7.0 3.0 Adjust for different size Θ Θ 4 1
6 9 11.6 5.0 Adjust for different task Ο Θ 4 1
7 9 11.6 5.0 Easy to carry Θ ▲ 2 4
8 9 7.0 3.0 Easy to put on Ο 2 3
9 9 2.3 1.0 Confortable used Θ Ο Ο 3 2
10 1 7.0 3.0 Easy to operate ▲ 2 4
11 9 7.0 3.0 Robust Θ Θ Θ Ο Θ Θ 2 3
12 9 11.6 5.0 Anti‐corrosion Θ Ο Ο 4 2
13 9 7.0 3.0 Aesthetic Θ Θ Ο ▲ ▲ 2 3
14
Target or Limit Value
Difficulty
( 0=Easy to Accomplish,
10=Extremely Difficult )
Max Relationship Value in Column 9 9 9 9 9 9 3 9 9
Weight / Importance 62.8 279 258.1 167.4 62.8 195.3 74.4 258 167.4
Relative Weight % 4.2 18.6 17.2 11.1 4.2 13 4.9 17.2 11.1
Rank order 6 1 2 4 6 3 5 2 4
Type of material
Our Company
Competitive Analysis
(0=worst, 5=best)
Row #
Max. Relationship Value In Row
Relative Weight
Weight / Importance
No. of colour
size
Fatigue
Toughness
Competitor 1
3 5 7 3 3 6 2 9
Hardness
Environment effect
Physical appearance
Cost
Quality
Characteristic
Demanded
Quality
12. 8
7.0 PRODUCT DESIGN SPECIFICATION (PDS)
i. Product Title
Arthritis Hand-Aids
ii. Purpose
To provide the hand arthritis people a convenient way to grip, hold and apply force
on something.
iii. New and Special Features
‐ Combination of various function in one tool
‐ Ergonomic handle for better gripping
‐ Adjustable size of gripper to grip objects with different diameter
iv. Competition
Compete against other single function arthritis tool
v. Intended Market
‐ Sell to people who have hand arthritis.
‐ Product will be promoted through medical centre
vi. Need for product
‐ User survey has shown 85% of respondent will to pay more for an aid equipment.
‐ Most of them having difficulty in dressing and grooming, eating.
‐ Activities such as hold and grip are highly ranked as hard to be performed, which
means they demand a tool that helps them to overcome these difficulties.
‐ The designed product should be portable, weight and size are to be concerned.
vii. Relationship to existing products line
This is a start-up venture. No other products currently exist.
viii. Price
We anticipate selling a hand-aids tool for around RM30-50
13. 9
ix. Functional Performance
‐ Allow to hock clothes
‐ Allow to open soft drink cans
‐ Allow to grip on round objects such as door knob, bottle cap
‐ Able to be applied force 100N without failure
x. Physical Requirements
‐ Length 30cm
‐ Light Weight 500g
‐ Cylinder shape with sphere head and round edges
‐ Smooth but not slippery surface
xi. Service Environment
Product Material should be stable from 0°C to 100°C
xii. Life-cycle issues
Gripping mechanism should not fail for 5000 cycles.
xiii. Human Factors
‐ No sharp edges or corners to cause cuts or snag clothing
‐ Handle must be ergonomic shape for comfortable purpose
‐ User friendly, simple to operate the function
xiv. Corporate Constraints
‐ Must be marketed within 1 year
‐ Must confirm to corporate code of ethics
xv. Legal requirements
No toxic materials to be associated with material
14. 10
8.0 FUNCTIONAL DECOMPOSITION
In solving any complex problem, a common tactic is to decompose the problem into
smaller parts that are easier to manage. When customer’s need is captured, a model of
showing how the product should function is required to clarify and design the product
architecture. Product architecture is the arrangement for the physical elements of a
product to carry out its required functions.
In this report, we will develop process description using an Activity Diagram. A
high level user activities are networked to show the full cycle of a product. Next, by using
the Activity Diagram, a function structure for the product is formulated. Function
structure is defined as an input-output model that maps energy, material and signal flows
to a transformed and desired state. A higher activity diagram is shown in appendix C1
and the functional modeling is shown in appendix C2 to C5.
The method to perform functional decomposition are:
i. State the overall function that needs to be accomplished
Develop a “black box” model of the product to shows the flow in and flows out
need to be identified.
ii. Create descriptions of sub-functions
Decomposing the overall function in “black box” into sub-functions. Each sub-
function represents a change or transformation in the flow of energy, material or
information.
iii. Arrange the sub-functions in logical order
For our problem this is a trivial step, but for other design problems it can be major
to follow the sequence of sub-functions
iv. Refine the sub-functions
Refinement stops when a sub-function can be fulfilled by a single solution that is an
object or action, and the level of detail is sufficient to address the customer needs.
15. 11
9.0 CONCEPT GENERATION
The techniques of concept generation including Trigger words, Checklist, Analogy,
Morphological Analysis, and Brainstorming. In this report, we are using Morphological
Analysis where a Morphological Chart is developed to generate 15 concepts. The concept
combination is shown in appendix D1 to D3
A morphological chart is a visual way to capture the necessary product functionality
and explore alternative means and combinations of achieving that functionality. For each
element of product function, there may be a number of possible solutions. The chart enables
these solutions to be expressed and provides a structure for considering alternative
combinations. The method to construct a Morphological Chart are:
i. List the product functions
List functions according to a predetermined order - most important, position in
structure, energy flow, information flow. Care should be taken to list functions and
not components - e.g. 'warning indicator' rather than 'bell'. Always ask 'what function
is this component fulfilling?' Each function should be mutually exclusive.
ii. List the possible 'means' for each function
Think about new ideas, as well as known solutions or components and where possible
ideas should be expressed visually as well as in words. Any important characteristics
of the solutions should be recorded. Try to maintain the same level of generality for
each possible solution.
iii. Chart functions and means and explore combinations
Draw up a chart containing all possible sub-solutions. This is the 'morphological chart'
which should represent the total 'solution space' for the product. Try wherever
possible to express all options visually as to identify feasible combinations of sub-
solutions. The total number of combinations may be very large, so they may need to
be limited to the most feasible or attractive options. Name each viable combination as
a potential solution for further evaluation later.
16. 12
9.1 Morphological Chart
Sub functions
Concepts
A B C D E
1.0 Hold the handle of tools
1.1 Grip tool Flat
Rectangular
Centre Hollow
Dent/Groove
Curved
Cylinder
1.2 Grasp to use
tool
Rough & Grain
Surface
Smooth &
Shiny Surface
Rubber Layer
Surface
2.0 To Clip Object
2.1 Positioning
the Clipper
Fixed
Extend &
Retract
Flipped
2.2 Picking up
objects
Pliers Style
Double Fork
Style
Clamping Style
2.3 Using the
clipping
Mechanism
Push button
Slide button
17. 13
3.0 To grip object
3.1 Fitting object
into gripper
Round Head
Square Head
Pentagon
Head
Hexagon Head
3.2 Positioning
the gripper
Fixed
XY plane 180°
Adjustable
XZ plane 180°
Adjustable
XY & XZ plane
180° Adjustable
3.3 Holding
object in
gripper
Flat Teeth
Rough Teeth Full & Flat Full & Rough
3.4 Opening or
turning an
object
Hand Rotate Automatic
Rotate
3.5 Using the
gripper
mechanism
Push Button
Slide Button
4.0 To hook object
4.1 Picking up
object
Sharp Head
Hook
Flat Head
Hook
Round Head
Hook
18. 14
9.2 Concept Combination
Subfunctions
Concepts
A B C D E
1.1
Grip tool
Flat
Rectangular
Centre Hollow
Dent/Groove
Curved
Round
Cylinder
1.2
Grasp to use
tool
Rough & Grain
Surface
Smooth &
Shiny Surface
Rubber Layer
Surface
2.1
Positioning
the Clipper
Fixed
Extend &
Retract
Flipped
2.2
Picking up
objects
Plyer Style
Double Fork
Style
Clamping Style
2.3
Using the
clipping
Mechanism
Push button
Slide button
3.1
Fitting object
into gripper
Round Head
Square Head
Pentagon
Head
Hexagon Head
3.2
Positioning
the gripper
Fixed
XY plane 180°
Adjustable
XZ plane 180°
Adjustable
XY & XZ plane
180°
Adjustable
3.3 Holding
object in
gripper
Flat Teeth
Rough Teeth
Full & Flat
Full & Rough
3.4 Opening or
turning an
object
Hand
Automatic
3.5 Using the
gripper
mechanism
Push Button
Slide Button
4.1 Picking up
object
Sharp Head
Hock
Flat Head
Hock
Round Head
Hock
19. 15
10.0 CONCEPT EVALUATION
Evaluation involves comparison, followed by decision making. To make a valid
comparison the concepts must exist at the same level of abstraction. There are many
techniques for concept evaluation such as Comparison based on absolute criteria, Pugh’s
concept selection method, Measurement scales, Weighted Decision Matrix, Analytical
Hierarchy Process (AHP), and Methods of Decision Analysis.
In this report, we are using Pugh’s concept selection method since it is a
particularly good method for deciding on the most promising design concept at the concept
stage. This method compares each concept relative to a reference or datum concept and for
each criterion determines whether the concept in question is better than, worse than, or
about similar to the reference concept.
This matrix-based approach was proposed by Pugh (1991), which is also known as
Concept Screening. The steps being taken to a construct Pugh’s concept selection table are:
Step 1: Generate an assortment of ideas or concepts
Step 2: Prepare a criteria list
Step 3: Pick a datum
Step 4: Evaluate each alternative by rating them with “+”, “-” and “0”
Step 5 Rank the concept by referring the sums up scores
Step 6 Choose 6 best optimised hybrid concept
Step 7 Seek opportunities for improvement
Step 8: Apply more rigorous engineering disciplines to hybrid design
21. 17
10.2 Concept Comparison
From the Pugh’s concept selection method, the six concepts with highest rank are selected
for further evaluation. The six chosen concepts are concept(4), (5), (6), (8), (12) and (14).
They are to be compared in terms of advantages and disadvantages, where the comparison
of concept (4) is shown as below and remaining is in appendix E1 to E5. The visual view
of six concepts is also shown through hand sketches for better understanding.
I) Concept (4)
Advantages Disadvantages
a) More application and task can be
performing.
b) Very ergonomic such as comfortable to
hold and use.
c) The gripper and clipper can be adjust for
desired size and high accuracy to lock it
properly with the helps of slide button and
other mechanism.
d) Special features such as the clipper can in
and out from the holder.
a) Increase the manufacturing process,
cost and design.
b) Will lower the durability and life
cycles of product due to adding more
function.
c) Do not have high degree of freedom to
move the head part due to fixed.
d) More different material has to use and
must follow standard quality for
medical product.
22. 18
11.0 CONCEPT SELECTTION
Concept selection is the process of narrowing the set of concept alternatives under
consideration. In this report, we are using the Weighted Decision Matrix method which
also known as Concept scoring because it is easy to understand and apply. Concept scoring
is used when increased resolution will better differentiate among competing concepts. In
this stage, we weighs the relative importance of the selection criteria and focuses on more
refined comparisons with respect to each criterion. The concept scores are determined by
weighted sum of ratings.
This approach can be good at indicating the front runners, but numerical methods
like this can be dangerous, as they tend to imply only one 'right' answer. It should always
be remembered that both the weightings and the ratings are subjective and arbitrary, and
thus although a quantitative answer is gained, it too is subjective. This approach is also
extremely sensitive to small changes and it can be easy to 'cook the books', so it needs to
be used with caution. The method to construct a Weighted Decision Matrix table are:
i. List the most important features
These should have been determined during the product definition phase and form
the criteria against which rival solutions will be judged.
ii. Determine weightings
Some features will be more critical than others. Assign weightings to each, so that
their relative merits are accounted for. Ideally, the weightings should be
determined in partnership with the target customers.
iii. Rating each option
Suppose the rating should be led by customers to remove personal bias from
amongst the design team.
iv. Calculate the weighted totals
Multiply the score by the weighting for each feature and sum the totals.
23. 19
11.1 Weighted Decision Matrix
1 . Manufacturing cost 25% 3 0.75 3 0.75 5 1.25 3 0.75 2 0.50 3 0.75
2 . Material 5% 4 0.20 4 0.20 4 0.20 4 0.20 4 0.20 4 0.20
3 . Weight 3% 4 0.12 2 0.06 4 0.12 2 0.06 2 0.06 2 0.06
4 . Aesthetic 2% 5 0.10 4 0.08 1 0.02 5 0.10 3 0.06 3 0.06
5 . Durability 5% 3 0.15 2 0.10 2 0.10 3 0.15 2 0.10 2 0.10
6 . Portability 10% 2 0.20 3 0.30 3 0.30 4 0.40 2 0.20 3 0.30
7 . Comfortable To Hold and Use 20% 5 1.00 4 0.80 3 0.60 4 0.80 3 0.60 3 0.60
8 . Ease of clipping objects 10% 4 0.40 2 0.20 4 0.40 4 0.40 4 0.40 4 0.40
9 . Ease of gripping objects 10% 4 0.40 2 0.20 3 0.30 3 0.30 3 0.30 2 0.20
10 . Ease of hocking objects 10% 5 0.50 5 0.50 3 0.30 3 0.30 5 0.50 3 0.30
Total Score
Rank
Continue ?
R= Rating ( 1 = Inadequate, 2 = Weak, 3 = Satisfactory, 4 = Good , 5 = Excellent )
S = Weighted Score
R
( 6 )
R S
( 8 )
R S
( 12 )
R S
( 14 )
R S
2.92
6
No
2.97
5
No
3.59
2
No
3.46
3
No
3.82
1
Yes
3.19
4
No
SSelection Criteria
Concepts
Weight
( %)
( 4 )
R S
( 5 )
11.2 Final Concept
From the weighted decision matrix table, we have determined concept(4) as the most
preferable concept since it has the highest score among the other concepts. The remaining
concepts will be revised and keep as reference.
In conclusion, our final concept is concept (4) which will be proceeded to
embodiment design and various analysis.
24. 20
12.0 EMBODIMENT DESIGN
The definition of embodiment design according to Pahl and Beitz (2007) runs as follow:
“Embodiment Design is the part of the design process starting from the principle solution
or concept of a consumer product. The design should be developed in accordance with
engineering and economical criteria”. This is a pure technical and economical
consideration of Embodiment Design but a product has more aspects than only the
technical and economical ones. A product can also bring aspects about emotion, beauty,
appeal and happiness the other values in live. People like to pay for these values if the
earnings are higher than the cost of the basic needs.
The embodiment design refines the abstract concepts to blueprints. A blueprint
denotes a model of the institutional rules that is more concrete than in the concept but still
independent of implementation details. In other words, the concept comprises at most a
verbal description of the institutional rules or algorithms. As such, many different
blueprints can be found that realize the same concept. During the embodiment design this
verbal descriptions are transformed into a model with sufficiently low level of abstraction
that traditional design techniques may be applied in order to implement it: the concept
becomes form (Pahl & Beitz 2007).
The Embodiment Design phase is the part of the design process which is concerned
about the production of the product concept, the engineering and the economical feasibility.
The production contains the parts making and the product assembling.
In brief, the embodiment process is the bridge between the conceptual stage of the
design process and the detail design stage. A more detailed analysis of the selected
concepts is undertaken in the embodiment stage of the design process. In this report, our
embodiment design consist of Product Architecture, Failure Mode and Effects Analysis
(FMEA), and Design For X.
25. 21
12.1 Product Architecture
There are 4 basic steps that need to be constructed in order to generate the product
architecture. First, list out the functional structure of the product and arrange in proper
location that close to each other (Appendix F1). Second, categorize and combine the
structures/elements into few building blocks according to their function properties
(Appendix F2). Third, generate the components hierarchy structure and simple geometric
view of product (Appendix F3). Finally, determine the incidental interactions between the
building blocks during operation (Appendix F4).
For the functional structure of the product, the black boxes functional structures
that generated at previous part were simplified and combined together. The inputs of the
model are hand, energy operating situation and after used condition. After using, the
outputs of the model include sound, object and energy released. The energy transit line
for each function will be represented by different colors. For example, the energy transit
line for gripping is in red color.
The modular chunks will be established with combine all the related functional
structures into a block. The major functions of the product include gripping, clipping,
rotate for objects opening and hanging. The main function of handle is to magnify the
applied energy into larger torque. At the rough geometric part section, list out all the
product’s components except the standard parts like screws and nuts. Arrange the
components into hierarchy structure and determine the interaction of the components
between and within chunks. The geometric layout of product is shown in front, back and
also side view.
In the incidental interaction part, the interaction elements include vibration,
bending, stress concentration, unbalance force and environment effect. When hanging the
object by hook, the stress concentration and vibration occur near to the cross head part
due to the screw location. At rotating the adjustable and cross heads, force that applied to
generate torque will bend the handle. Normally, the cross head will be used at kitchen or
bathroom so the environment conditions such as acidity of detergent, water temperature
will give the effect to the product surface. The unbalance force exist because the total
weight of the cross head and adjustable head at the top is not exact same with the weight
of clipper system at the bottom.
26. 22
12.2 Failure Mode & Effect Analysis (FMEA)
Failure Mode and Effects Analysis (FMEA) is a method to identify potential failure
modes for our Arthritis tool product, to assess the risk associated with those failure modes,
to rank the issues in terms of importance and to identify and carry out corrective actions
to address the most serious concerns. To assess the risk associated with the issues
identified during the analysis and to prioritize corrective actions, Risk Priority Numbers
(RPNs) method is used. RPN evaluated by this formulation RPN = Severity (S) x
Occurrence (O) x Detection (D).
For this method, our team was decided to choose picking object, clipping object,
gripping object and opening water tab as a part function. This part function based on the
overall functions and functional modeling for product that being developed. It is
importance to rating the severity, occurrence and detection by refer the guidelines from
books and notes. The purpose by referring the guidelines to give better explanation on
how to numbering and rating the factors mention properly and not by suggestion.
By applied FMEA, It can contribute to improved designs for products and
processes, resulting in higher reliability, better quality, increased safety, enhanced
customer satisfaction and reduced costs. The tool can also be used to establish and
optimize maintenance plans for repairable systems or contribute to control plans and
other quality assurance procedures. It provides a knowledge base of failure mode and
corrective action information that can be used as a resource in future troubleshooting.
Appendix G1 shows the Failure Mode and Effect Analysis (FMEA) for picking
and clipping Arthritis tool product. Meanwhile, Appendix G2 shows the Failure Mode
and Effect Analysis (FMEA) for gripping and opening water tab for Arthritis tool product.
27. 23
12.3 Design For X (DFX)
X in DfX stands for manufacturability, inspectability, recyclability and others. These
words are made up of two parts: life cycle business process (x) and performance measures
(bility), that is X=x+bility. If a DfX tool focuses on one life cycle process and uses more
than one performance metrics, it is referred to as tool of the “Design for the Life Cycle”
type. On the other hand, if a DfX tool focus on one performance metric but covers a range
of life cycle processes, it is then referred to as a tool of the “Design for the
Competitiveness” type.
Most Popular DfX Tools:
Design for Assembly/ Disassembly/ Maintabability (DfA)
Design for Cost (DfC)
Design for EMC (DfE)
Design for Installation (DfI)
Design for Quality (DfQ)
Design for Recycling (DfR)
Design for Reuse (DfR)
Design for Serviceability (DfS)
Design for Speed (DfS)
Design for Six Sigma (DfSS)
Design for Testability (DfT)
Design for Warranty (DfW)
Design for Usability (DfU)
Design for Validation (DfV)
A generic DfX model can provide a platform for integrating a DfX tool with other
decision support systems used in product development such as CAD/CAM (computer
Aided Design and Manufacture), CAPP (Computer Aided Production management), to
facilitate the flow of data and decision between them. Successful DfX tools define clearly
28. 24
their specific areas of concern and thus provide the essential focus for the project team to
make the best use of resources available to them. Below stated the function of a DfX tool:
1) Gather and present facts about products and processes
2) Clarify and analyze relationship between products and processes
3) Measure performance
4) Highlight strengths and weaknesses and compare alternatives
5) Diagnose why an area is strong or weak
6) Provide redesign advice on how a redesign can be improves
7) Predict what-if effects
8) Carry out improvements
9) Allow iteration to take place
As it was too many of DfX tools, it have become difficult to choose a DfX which is
most appropriate for the problem at hand. There is a few general guidelines regarding
when and where to apply what DfX, firs, for tool of Design for Assembly, it should be
used to rationalize products assortments and structures before other types of DfX tools.
Second, the number of factors such as availability, applicability, vendor experience and
others affected which DfX tool should be used. The last but not least, DfX should be used
as early as feasible and the problem is and where it lies determine what DfX to use.
Furthermore, for the design of product arthritis hand tool, there are few of tools have
been selected and focused for the design analysis, as stated below:
Design for Assembly
Design for Manufacturing
Design for Reliability
Design for Human Factors
Design for Environment
29. 25
12.3.1 Design For Assembly (DfA)
DfA were introduced in 1970s, one of the earliest works, Hitachi Assemblability
Evaluation Method (Hitachi AEM). DfA once pushed by automation technology but now
more in manual assembly. DfA meaning as the design of the product for the ease of
assembly. Furthermore, it is defined as making decision in product development related
to products, and process and plants. The aim is to simplify the product so that the cost of
assembly is reduced. Research found that DfA can be the key to high productivity in
manufacturing. The Boothroyd-Dewhurst method for DfA process follow these steps:
i. Select an assembly method for each part
ii. Analyses the parts for the given assembly methods
iii. Refine the design in response to shortcomings identified by the analysis
iv. Loop to step 2 until the analysis yields a sufficient design
Figure 11.3(a): Arthritis Hand Aids product.
C1
C2
B
A C
A1
A2
30. 26
As for part A, the handle, it is actually made of two semi-cylindrical shape, we
mark it as A 1 and A 2. Both parts been engage by two snap-fit joints, located at upper
and lower section A. We have decided to choose type annular snap-fit joints because we
can designed the joint to be either detachable, difficult to disassemble or inseparable,
depending on the dimension of the insert and the return angle. We have decided to make
our product with high maintainability, so the annular snap-fit must be a detachable one.
We have mark the inserts located at A 1 with diameter of 3 mm and the hub located at A
2 with diameter of 5 mm.
Figure 11.3(b): Typical annular snap-fit joint.
For part B, the clipper section, it include bottom and upper clipper. Both was
engage together by fastener. Later, to fit the combine clipper (metal) with the plastic part,
still using fastener. To make sure that the joint between the plastic and metal allows the
plastic part to expand without regard to the expansion of the metal part, we are adding a
shoulder fasteners. When the clipper part itself was assemble, it was engage to the
handler also by a fastener. For part C, the head section which include tab opener and door
opener, both located on opposite side, we mark tab opener as C 1 and door opener as C 2.
To engage C 1 and C 1 use fastener located at the back of each part then when both was
assemble, to fit it into the handler, also using a fastener. For hook attached at Part C, it
was engage to the head by screw fastener.
A 2 A 1
Insert Hub
31. 27
Figure 11.3(c) : Use of shoulder fasteners between the fastener and the plastic.
The Therbligs motions required for operator during assembly process are grasp,
position, hold and lastly assemble, applied for all part A, B and C. There are some basic
guidelines for DfA that our group design try to apply to product arthritis hand tool:
Guidelines Application to product
Minimize part count by incorporating
multiple functions into single parts
Part C, there were two different function,
assemble into single parts.
Modularize multiple parts into single
subassemblies
Part B was attached directly to the handler
subassemblies.
Assemble in open space, not in confined
spaces; never bury important components
However, Part C was designed to be buried
under handler, as for aesthetic and
ergonomic decision.
Make parts such that it is easy to identify
how they should be oriented for insertion
The upper and lower of handler differentiate
by the button channel shape, operator can
easily identified it.
Prefer self-locating parts Part A was insert by snap-fit joints.
Eliminate tangly parts Part B was retract back after use to avoid be
tangled outside product.
Color code parts that are different but shaped
similarly
We may color code at tab and door opener
head for this purpose.
Design the mating features for easy insertion Part C apply this in order to insert it to the
handler.
Eliminate fasteners We cannot avoid this as all part was best fit
by fastener to make sure of its engagement.
Place fasteners away from obstructions;
design in fastener access
All fasteners on the product has its own
access.
Deep channels should be sufficiently wide to
provide access to fastening tools; eliminate
channels if possible
Fastener was attached before the Part A was
snap-fit together, so fastening tool easily
reach to fasteners.
Ensure sufficient space between fasteners and
other features for a fastening tool
No fasteners was designed close to each
other on the product.
32. 28
12.3.2 Design For Manufacturing (DfM)
DfM is the process of proactively designing products to optimize all the manufacturing
functions such as fabrication, assembly, test, procurement, shipping, delivery, service and
repair. Furthermore DfM is to assure the product has the best cost, quality, reliability,
regulatory compliance, safety, time-to-market, and customer satisfaction.
Besides that, it is important to use specific design guidelines for part to be
produced by specific processes. Part A and C was completely produced by plastic
injection molding process. Besides that, polypropylene plastic is well known for molding
process. Part B, the clipper also was made by same material where it is made in
house. Same as with fastener, we are using the standard size and shape. The product also
was design avoiding mirror image parts, it can be use both right or left hand modes.
Although the product not design symmetrical, worker or robot could still easily install the
part either upward or backward. It means that product can be installed starting first by
Part C or Part B. Any other way, but it must the assemble of Part A become the last
process.
12.3.3 Design For Reliability (DfR)
Reliability is the ability of an assert to survive a specific period of time without failure.
At present there are three main approaches to ensuring that a design will be reliable:
reliability prediction, design techniques and development or pre-production reliability
testing. From these, designers can model their designs quickly and simply to identify
areas which are most likely to cause reliability problems. In this report, has been included
design technique using Failure Mode and Effects Analysis (FMEA) as to determine the
product reliability.
33. 29
12.3.4 Design For Human Factors (DfHF)
Human factors discover and applies information about human behavior, abilities,
limitations, and other characteristics to the design of product and environments for
productive, safe, comfortable, and effective human use. As the product focused for
people with arthritis disease condition, they have certain capabilities and limitations, and
the product must be designed with an understanding of the patients component subsystem
requirements. Besides that, our group design have been referring to The Material
Information Society for Medical Material to make sure that material been decided is safe
for use of arthritis patients. The material been used is polypropylene plastic. We also
have referring to NIOSH’s guide for hand tools. From that, we have try to follow few
guidelines with our product design, stated as follow:
Guidelines Application to product
Handle diameter is 1 ¼ inches to 2 inches
(31.75 mm to 50.8 mm)
The product has handle with diameter of
40mm.
For double-handled pinching, gripping, or
cutting tools, applied spring-loaded to
return the handles to the open position
The product clipper was attached with
spring-loaded in between.
For task requiring high force, tool’s handle
length must longer than widest part of
hand, between 4 inches to 6 inches ( 101.6
mm to 152.4 mm)
When consumer using either the clipper
part or opener part, their hand was in
between handler, length about 100 mm.
Table 11.3(a) : NIOSH’s guide for hand tools
34. 30
12.3.5 Design For Environment (DfE)
The goal of DfE is to enable design teams to create eco-efficient and eco-effective
products while adhering to their cost, quality and schedule constraint. There at least two
types of guidelines, prescriptive and suggestive guidelines. Prescriptive is about what
designers should or should not do, also known as design rules. On the other hand,
suggestive is guidelines represent accumulated knowledge but not strict rules. Here are
steps to designing innovative products with minimal environmental impact:
1) Map the product lifecycle
2) Identify the main environmental impacts
3) Select relevant DfE strategies
4) Generate design concepts
Next, DfE guidelines was then are divided into four principles strategies, design for
dematerialization, design for detoxification, design for revalorization and design for
capital protection and renewal. Our group design decided to focus more on design for
revalorization which is seeks to recover, recycle or reuse the residual materials and
energy that are generated at each stage of product life cycle, thus eliminating waste and
reducing virgin resource requirement. This later was discuss more during topic of Product
Recovery, Reuse and Recycle.
35. 31
13.0 DETAILED DESIGN
In the engineering drawing of the Arthritis Hand Aids product, we have split it into 3
main section namely Head, Handle and Clipper. The Head section consists of sub-part
such as Adjustable Head, Tap head , Belt , Teeth, Screws and Hook. Whereas, the Handle
section consists of Top Handle, Bottom Handle, Top Button For Clipper, Bottom Button For
Teeth, Top Button For Teeth and Screws. Finally, the Clipper section consists of Upper Clipper,
Bottom Clipper, Pin, Spring and Screw. In this report, the parts such as screws, spring and
pin are not included in drawing because they are standard parts. By Using Solid Work
2010 software, the product is being sketched in 3D view as shown figure 12.0(a) and
figure12.0(b). The detail drawing of each sub-parts is also shown in this report in
appendix F1 to F5.
Figure 12.0(a) Arthristis Hand Aids (tap head 3D view)
Figure 12.0(b) Arthristis Hand Aids (adjustable head 3D view)
37. 33
13.2 Engineering Analysis
Engineering analysis is performed for two critical part which are handle and tap head.
The material Polyamides (PA) type 6 is selected for stress and displacement analysis
because it is the most-used engineering materials, with excellent impact strength,
moldability and paintability, fair heat resistance, and good wear and friction
characteristics. The analysis is shown as below:
13.2.1 Handle
I) Stress Analysis For Handle ( Force Applied =100N )
Figure 12.3(a) Von Mises Stress Analysis For Handle
38. 34
II) Displacement Analysis For Handle ( Force Applied =100N )
Figure 12.3(b) Displacement Analysis For Handle
III) Summary of Handle Analysis Results
39. 35
13.2.2 Tap Head
I) Stress Analysis For Tap Head ( Force Applied = 100N )
Figure 12.3(c) Von Mises Stress Analysis For Tap Head
II) Displacement Analysis For Tap Head ( Force Applied = 100N )
40. 36
Figure 12.3(d) Displacement Analysis For Tap Head
III) Summary of Handle Analysis Results
From the analysis done on the two components using Software Solid Word 2010,
the result differentiates based on the shade of colours. Blue area means that area is of a
lower stress and lower displacement, high stress and displacement the red is of the
opposite condition. Both components show that they can withstand the force being
applied without failure. Analysis for Mass properties for overall design is shown in
appendix H, the total mass of product is 320g and the volume is 28.60m3
.
41. 37
14.0 MATERIAL AND COSTING
14.1 Material Selection
By using Cambridge Engineering Selector (CES) 2005, we have set a few stage to filter
according to the desired range of material properties.
Stage 1
For Stage 1, material which are having young modulus, 0.1GPa and fracture toughness
0.1MPa /m2
is taking into consideration. This is to ensure our product can withstand
certain amount of force without failure.
Figure 14.1(a) Material Selection-Stage 1 using CES
42. 38
Stage 2
For stage 2, material which has good durability against wear and fresh water is taken into
consideration. The product should have good resistivity to water because it is used to
open water tap in bathroom or a washing sink. The product should also not easy to tear
and wear so that it will have a longer life cycle.
Figure 14.1(b) Material Selection-Stage 2 using CES
Stage 3
Finally, the stage 3 is a limit stage where we limit the material to polymers, price of
material below RM15/ kg and a maximum density 1200 kg/m3
This will help in narrow
down the choices and we can compare the properties of remaining material easily.
Figure 14.1(c) Material Selection-Stage 3 using CES
43. 39
14.2 Cost Estimation
In order to fabricate a Arthritis Hand Aids, there are 9 manufactured parts and another 9
purchased parts need to be assembled to become the final product. We have chosen
Polyamides (PA), as the material to fabricate our product since it has average material
cost, high durability against water and wear. The details of PA is shown in appendix I.
i. Manufactured Parts ( Total Manufacturing Cost =RM20 )
Part
No.
Description Material volume
(m3
)
Density
(kg/m3
)
Mass
(kg)
(RM)
cost/ kg
Qty
Cost
(RM)
001 Adjustable head PA 3.0E-04 1130 3.4E-01 14.5 1 4.92
002 Belt PA 7.5E-06 1130 8.5E-03 14.5 1 0.12
003 Bottom clipper PA 6.0E-06 1130 6.8E-03 14.5 1 0.10
004 Bottom handle PA 8.0E-05 1130 9.0E-02 14.5 1 1.31
005 Hook PA 6.0E-06 1130 6.8E-03 14.5 1 0.10
006 Tap head PA 3.0E-04 1130 3.4E-01 14.5 1 4.92
007 Teeth PA 8.0E-06 1130 9.0E-03 14.5 4 0.52
008 Top handle PA 8.0E-05 1130 9.0E-02 14.5 1 1.31
009 Upper clipper PA 6.0E-06 1130 6.8E-03 14.5 1 0.10
Total Material Cost 13.39
ii. Purchased Parts
Item
No.
Description Material (RM)
Cost/Qty
Qty. Cost (RM)
1 Pin Cast iron 0.40 1 0.40
2 Spring Cast iron 0.80 1 0.80
3 Screw for clipper Cast iron 0.10 1 0.10
4 Screw for teeth Cast iron 0.10 4 0.40
5 Top button for clipper Polyamides (PA) 0.50 1 0.50
6 Bottom button for teeth Polyamides (PA) 0.50 1 0.50
7 Screw for button up Cast iron 0.10 1 0.10
8 Top button for teeth Polyamides (PA) 0.50 1 0.50
9 Screw fot head and handle Cast iron 0.10 4 0.40
Total Purchasing Cost 3.70
Overall Cost = Manufacturing Cost + Material cost + Purchasing Cost
= RM 20 + RM 13.39 +RM 3.70
= RM 37.09 /product#
44. 40
15.0 CONCLUSION
We have started this product design project by forming group, listing out all the task to be
done using a Gantt Chart. Eight ideas has been generated during the brainstorming
session, where decision is made by everyone to proceed our project with a product
namely "Arthritis Hand Aids".
We have identified the problems and define three main objectives of designed
product to be achieved at the end of project. The designed product shall comprise the
good elements such as features, performance and convenience. A survey is conducted
where 30 questionnaires is distributed to gathered information and needs of customers.
The surveys shows that most of respondent are having difficulties in performing daily
task such as open a door knob, open water tap, picking up clothes and other activities.
The collected information enables us to proceed with Quality Function
Deployment(QFD), where a House of Quality is developed to show the priority of
improvement should be given to size of product and mechanical properties such as
fatigue and hardness.
Next, we have developed an activity diagram and functional modeling which
comprises the 4 main activities namely Gripping, Opening, Picking and Clipping. After
which, we proceed to the concept generation by using a Morphological to obtain 15
different combination of sub-function concepts. We have evaluated the 15 concepts using
Pugh’s Concept Selection then reduced to 6 concepts. The remaining 6 concepts are
being further compared through Weighted Decision Matrix, eventually the concept(4) is
chosen as the final concept.
In this report, our embodiment design consist of Product Architecture, Failure
Mode and Effects Analysis (FMEA), and Design For X. For the detail design, we have
split the product into 3 main section namely Head, Handle and Clipper. CAD drawing of
each parts is skectched, follow by an Exploded View and Bill Of Material (BOM) which
shows that product consist of 18 parts.
45. 41
The engineering analysis shows that the handle part can withstand 100N force and
the tap head can withstand 50N force. Polyamides (PA) is selected to fabricate some parts
our product whereas other standard parts is purchased. The overall cost for our product is
RM37.09 which satisfy the statement in PDS.
In brief, our objectives in this project is achieved because we have developed a
tool to assist the hand arthritis people to perform certain daily task. The tool is
multifunction and better than current existing design since we the have the adjustable
gripper head which allow to grip different diameter objects, as well as the extendable and
retractable clipper which is convenient to use and store.
46. 42
16.0 REFERENCES
Dieter, G.E. 2000. Engineering Design: A Materials and Processing Approach (3rd
Edition), New York: McGraw Hill Inc.
Moultrie, J. 2011. Morphological Charts.
http://www.ifm.eng.cam.ac.uk/dmg/tools/concept/morph.html
Otto, K.N. and Wood, K.L. 2000. Product Design: Techniques in Reverse Engineering
and New Product Development, Prentice Hall.
Pahl, G. and Beitz, W. 2007. Engineering Design - A systematic Approach (2nd Edition),
London: Springer-Verlag.
Quality-One International, Inc. 1995-2001. QFD (Quality Function Deployment).
http://www.quality-one.com/services/qfd.php
ReliaSoft Corporation, 2004. Basic Concepts of FMEA and FMECA.
http://www.weibull.com/hotwire/issue46/relbasics46.htm.
Sullivan, L.P., 1986. Quality Function Deployment. Quality Progress, pg 39-50.
Ulrich, K.T. & Eppinger, S.D. 2007. Product Design and Development (4th edition),
McGraw-Hill.
Ullman, D.G. 2003. The Mechanical Design Process (3rd Edition), New York: McGraw-
Hill Inc.
David, M.A. 2011. Design For Manufacturability.
http://www.design4manufacturability.com/DFM_article.htm
47. 43
Appendix A1
i. Gym Equipment For Handicap
Handicaps often cannot use standard workout
equipment, so they need alternatives.
The designed equipment is comfortable and allows
those with physical handicaps to get the exercise that
they need to be healthy
ii. GPS Holder At Motorbike
Motorbikers having difficulty in using GPS while they
are travelling, they need something to hold the GPS.
The designed holder shall easy to install and release
on the vehicle, provide extra safety for the GPS
devices
iii. Foldable And Adjustable Chair
The common chairs are with fixed height and
consume space to store it.
The designed chair shall not too heavy, bulky, or
complicated, meanwhile it should be portable and
stackable, provide suitable height for adult or children.
iv. Emergency Car Key Chain
The designed car key chain is useful during
emergency such as during an accident, being trapped
in car. It comprises a safety blade seat belt cutter,
steel point auto glass breaker, battery powered LED
light and sonic alarm sound
48. 44
Appendix A2
v. Arthritis Multifunctional Tools
A multifunctional tools that helps the arthritis patients
to grip object is designed since some daily performed
action might cause pains on their joints.
Example of functions: bottle opener, key turner, door
knob opener, tap turner etc
vi. Adjustable Allen Key
A common allen key set consists of different head
sizes allen key.
The newly designed adjustable allen key is to
integrated all head sizes into a single component.
vii. Automatic Lamp
The ordinary lamp post in a park or garden can be
improved to be self-supply electricity by adding a
solar panel.
It recharged by sunlight and automatic turning on at
dusk with a built-in light sensor.
viii. Multifunctional Torch Light
A torch light is very useful during jungle tracking or
during black out at night
A multifunctional torch light is to be designed for long
period outdoor activities purpose, has a solar panel to
recharge itself and also charge other electronic items
such as handphone, and as a defense tool
53. 49
Appendix B5
Questionnaire Part I
Part I - Question
I-A1 : Dress yourself with shoelaces and buttons
I-A2 : Shampoo your hair
I-A3 : Brushing teeth using toothbrush
I-B1 : Stand up from straight chair
I-B2 : Get in and out from bed
I-B3 : Get in and out from car
I-C1 : Lift a full glass to your mouth
I-C2 : Using fork and spoon / chopsticks
I-C3 : Using hand to hold and lift food to your mouth
I-D1 : Walk on flat ground
I-D2 : Walk on uneven ground
I-D3 : Climbing up and down of stairs
Question No I-A1 I-A2 I-A3 I-B1 I-B2 I-B3 I-C1 I-C2 I-C3 I-D1 I-D2 I-D3
Total Count of
(3) And (4)
25 14 21 18 16 15 19 23 17 9 14 17
Relative Frequency 83.3 46.7 70.0 60.0 53.3 50.0 63.3 76.7 56.7 30.0 46.7 56.7
Table 4.1 Total Count Of (4) And (5) And Relative Frequency For Questions In Part I
Figure 5.1 Pareto Diagram - Frequency Of Responses Against Question Number
83.3
76.7
70.0
63.3 60.0 56.7 56.7 53.3 50.0 46.7 46.7
30.0
0.0
20.0
40.0
60.0
80.0
100.0
Relative Frequency ( % )
Question No.
Pareto Plot of Responses ‐Part I
54. 50
Appendix B6
Questionnaire Part II
Part II - Question
II-A1 : Wash and dry your body
II-A2 : Get on and off the toilet
II-B1 : Reach something from above your head
II-B2 : Bend down to pick up something
II-C1 : Open door knob
II-C2 : Open water tab
II-C3 : Open jars lid
II-C4 : Open car doors
II-C5 : Pulling a shirt
II-C6 : Pull a plug
II-C7 : Pull a key from a door knob
II-D1 : Writing using pen
II-D2 : Taking a pan from kitchen
II-E1 : Driving a car
II-E2 : Run errands/ shopping
II-E3 : Do chores (vacuuming, laundry, gardening)
II-E4 : Swimming
Table 5.2 Total Count Of (4) And (5) And Relative Frequency For Questions In Part II
Figure 5.2 Pareto Diagram - Frequency Of Responses Against Question Number
Question No II-A1 II-A2 II-B1 II-B2 II-C1 II-C2 II-C3 II-C4 II-C5 II-C6 II-C7 II-D1 II-D2 II-E1 II-E2 II-E3 II-E4
Total Count of
(4) and (5)
13 13 25 22 24 23 25 22 16 22 23 22 23 20 16 25 27
Relative
Frequency
43.3 46.4 83.3 75.9 80.0 76.7 86.2 73.3 53.3 73.3 76.7 73.3 79.3 69.0 53.3 83.3 90.0
90.0 86.2 83.3 83.3 80.0 79.3 76.7 76.7 75.9 73.3 73.3 73.3 69.0
53.3 53.3
46.4 43.3
0.0
20.0
40.0
60.0
80.0
100.0
Relative Frequency (%)
Question No.
Pareto Plot of Response ‐Part II
55. 51
Appendix B7
Questionnaire Part III
Part III - Question
A : The weight of product
B(i) : Appearance- Shape
B(ii) : Appearance- Color
C : Size of the product
D : Alarm siren for emergency used
E : Product material
F : Easy to carry along at any time
Question No A B(i) B(ii) C D E F
Total Count Of (4) And (5) 26 11 6 23 13 19 22
Relative Frequency 86.7 36.7 20.0 76.7 43.3 65.5 73.3
Table 5.3 Total Count Of (4) And (5) And Relative Frequency For Questions In Part III
Figure 5.3 Pareto Diagram - Frequency Of Responses Against Question Number
Questionnaire Part IV
86.7
76.7 73.3
65.5
43.3 36.7
20.0
0.0
20.0
40.0
60.0
80.0
100.0
A C F E D B(i) B(ii)
Relative Frequency
Question No.
Pareto Plot of Response ‐Part III
57. 53
Appendix C1
Higher Activity Diagram
Purchase
Transport Un-pack Store
Operating Condition
Gripping Opening Picking Clipping
Move gripper
head to object
Adjust to fit
Apply force
to rotate
Pull out
Store
Attach cross
head to tab
Press to fit
the head
with tab
Apply force
to rotate
Pull out
Find out the
hang point
Attach hock
to hang
point
Pick up tool
and object
Release
object
Clipper
open
Positioning
Release
force to clip
Apply force to
release object
Pick up tool
and object
Adjust to loss
NO
NO
58. 54
Appendix C2
I) Picking Object (hook)
Find the hang
point on the
object
Reach tool near to
the object
Attach hook to the
hang point
Pick up the object
upwards
Locating the object
to desired place
Release object from
the hook
Object
Hand force
Situation Object
location
Hand
force
Holding
force
Hanging
location
Sound
Not
good
Good
Pull
force
Force
Object ,
Hand
59. 55
Appendix C3
II) Clipping Object
Larger
force
Force
Object
Stop motion
Clip objectMove to clip object
Guide to clipping
object
Convert to
larger force
Apply hand
force
Reach
clipper near
to the object
Hand
force
Situation
Low clip ability
Clipper
near to
object
Hand
Kinetic energy Force
High
force
Motion
Release motionRelease Force
Perfect
clipped object
Kinetic energy in
object, sound
60. 56
Appendix C4
III) Gripping Object
Object & hand
Force
Release tool
Object opened
Stop motion
Force
Apply larger
force to rotate
Sound
Apply force to
rotate
Adjust the
mechanism to
fix
Fix or loss
Holding force Hand force
Situation
Apply force to
attach the head
to object
Hand & Object
Force
Release motion
Force
Large force
61. 57
Appendix C5
IV) Opening Water Tap
Holding force
Hand force
Situation
Press and
fit
Object & hand
Apply force to
rotateWater tap shape
Sound,
Large Force
Convert to large
force
Force
Guide to rotate
Large force
Anticlockwise
motion
Low
High
Stop motion
After used
Apply opposite
rotating force
Water flow
condition
Convert to large
force
Large force
Guide to rotate Stop motionWater stop
Move and attach
to water tap
Force Release
Kinetic force
Hand
62. 58
Appendix D1
Sub functions
Concepts
(1) (2) (3) (4) (5)
1.1 Grip tool
Dent/Groove
Round
Cylinder
Curved
Dent/Groove
Dent / Groove
1.2 Grasp to use
tool
Rough & Grain
Surface
Rubber Layer
Surface
Smooth &
Shiny Surface
Rubber Layer
Surface
Rubber Layer
Surface
2.1 Positioning
the Clipper
Fixed
Extend &
Retract
Extend &
Retract
Extend &
Retract
Flipped
2.2 Picking up
objects
Clamping Style
Clamping Style
Double Fork
Style
Pliers Style
Double Fork
Style
2.3 Using the
clipping
Mechanism
Push button
Push button
Slide button
Slide button
Push button
3.1 Fitting object
into gripper
Hexagon Head
Round Head
Round Head
Round Head
Round Head
3.2 Positioning
the gripper
Fixed
XY & XZ plane
180°
Adjustable
XY & XZ plane
180°
Adjustable
Fixed
XY plane 180°
Adjustable
3.3 Holding
object in
gripper
Rough Teeth
Full & Rough
Full & Flat
Rough Teeth
Full & Flat
3.4 Opening or
turning an
object
Automatic
Automatic
Automatic
Hand
Automatic
3.5 Using the
gripper
mechanism
Push Button
Push Button
Slide Button
Slide Button
Push Button
4.1 Picking up
object
Sharp Head
Hock
Flat Head Hock Flat Head
Hock
Round Head
Hock
Round Head
Hock
63. 59
Appendix D2
Sub functions
Concepts
(6) (7) (8) (9) (10)
1.1 Grip tool
Flat
Rectangular
Centre Hollow
Dent/Groove
Round
Cylinder
Curved
1.2 Grasp to use
tool
Rubber Layer
Surface
Smooth &
Shiny Surface
Smooth &
Shiny Surface
Rough & Grain
Surface
Rubber Layer
Surface
2.1 Positioning
the Clipper
Flipped
Extend &
Retract
Extend &
Retract
Flipped
Fixed
2.2 Picking up
objects
Pliers Style
Double Fork
Style
Pliers Style
Double Fork
Style
Pliers Style
2.3 Using the
clipping
Mechanism
Slide button
Push button
Slide button
Slide button
Push button
3.1 Fitting object
into gripper
Square Head
Round Head
Pentagon
Head
Square Head
Square Head
3.2 Positioning
the gripper
XY plane 180°
Adjustable
XZ plane 180°
Adjustable
XY & XZ plane
180°
Adjustable
Fixed
Fixed
3.3 Holding
object in
gripper
Rough Teeth
Full & Flat
Flat Teeth
Full & Flat
Full & Rough
3.4 Opening or
turning an
object
Hand
Automatic
Hand
Automatic
Hand
3.5 Using the
gripper
mechanism
Slide Button
Push Button
Slide Button
Slide Button
Push Button
4.1 Picking up
object
Flat Head
Hock
Round Head
Hock
Flat Head
Hock
Sharp Head
Hock
Sharp Head
Hock
64. 60
Appendix D3
Sub functions
Concepts
(11) (12) (13) (14) (15)
1.1 Grip tool
Flat
Rectangular
Centre Hollow
Round
Cylinder
Curved
Flat
Rectangular
1.2 Grasp to use
tool
Rough & Grain
Surface
Rubber Layer
Surface
Smooth &
Shiny Surface
Rough & Grain
Surface
Smooth &
Shiny Surface
2.1 Positioning
the Clipper
Fixed
Flipped
Fixed
Flipped
Extend &
Retract
2.2 Picking up
objects
Double Fork
Style
Clamping Style
Pliers Style
Clamping Style
Clamping Style
2.3 Using the
clipping
Mechanism
Push button
Slide button
Push button
Slide button
Slide button
3.1 Fitting object
into gripper
Pentagon
Head
Round Head
Pentagon
Head
Pentagon
Head
Hexagon Head
3.2 Positioning
the gripper
XZ plane 180°
Adjustable
Fixed
XZ plane 180°
Adjustable
XY plane 180°
Adjustable
XY & XZ plane
180°
Adjustable
3.3 Holding
object in
gripper
Full & Flat
Full & Flat
Flat Teeth
Rough Teeth
Full & Rough
3.4 Opening or
turning an
object
Automatic
Automatic
Hand
Automatic
Automatic
3.5 Using the
gripper
mechanism
Push Button
Push Button
Slide Button
Push Button
Push Button
4.1 Picking up
object
Round Head
Hock
Round Head
Hock
Flat Head
Hock
Flat Head
Hock
Sharp Head
Hock
65. 61
Appendix E1
II) Concept (5)
Advantages Disadvantages
a) More application and task can be
performing.
b) Very ergonomic such as comfortable to
hold and use.
c) The gripper and clipper can be adjust for
desired size and high accuracy to lock it
properly with helps of slide button.
d) Very flexible to flip or move for
comfortable used by customer to perform
certain task.
e) Less power to gripping and turning since
it helps with automatic system.
a) Increase the manufacturing process,
cost and design.
b) Will lower the durability and life cycles
of product due to adding more function.
c) High tendency especially the part that
can be rotate or flip to fracture.
d) Increase the weight of the product
since additional power source such as
Battery cell is added.
66. 62
Appendix E2
III) Concept (6)
Advantages Disadvantages
a) More application and task can be
performing.
b) Certain part in the product such as gripper
or holder and fitting shape is easy to
make.
c) The gripper and clipper can be adjusted
for desired size.
d) Very flexible to flip or move comfortably
to perform certain task.
a) Increase the manufacturing process,
cost and design such as we have to
remove the sharp edges.
b) Not very ergonomic especially at the
tool holder since it is flat and the fitting
shape is not very convenience to fit
other shapes.
c) Will lower the durability and life
cycles of product due to adding more
function.
d) High tendency to fracture
especially the part that can be rotate or
flip.
67. 63
Appendix E3
IV) Concept (8)
Advantages Disadvantages
a) More application and task can be
performing.
b) Very ergonomic such as
comfortable to hold and use.
c) The gripper and clipper can be adjusted
for desired size.
d) Reduce type material of material since the
overall part not using rubber material.
e) Special features such as the clipper can in
and out from the holder.
a) Increase the manufacturing process,
cost and design such as we have to
remove the sharp edges.
b) It may be slippery to hold since no
rubber layer, not suitable to used when
the hand is wet.
c) Will lower the durability and life cycles
of product due to adding more function.
d) High tendency to fracture especially the
part that can be rotate or flip.
68. 64
Appendix E4
V) Concept (12)
Advantages Disadvantages
a) More application and task can be
performing.
b) Comfortable to hold and use.
c) The gripper and clipper can be adjusted
for desired size.
d) Unique and comfortable holder
e) Less power to gripping and turning since
it helps with automatic system.
a) Increase the manufacturing process, cost
and design.
b) Will lower the durability and life cycles of
product due to adding more function.
c) Do not have high degree of freedom to
move the head part due to fixed.
d) More different material has to use and
must follow standard quality for medical
product.
e) Increase the weight of the product since
additional power source such as Battery
cell is added.
69. 65
Appendix E5
V) Concept (14)
Advantages Disadvantages
a) More application and task can be
performing.
b) Very ergonomic such as comfortable to
hold and use.
c) The grip, grasp and clipping object can be
adjusted for desired size.
d) Unique and very comfortable holder
where the rough and grain surface reduce
the slippery.
e) Less power to gripping and turning since
it helps with automatic system.
a) Increase the manufacturing process, cost
and design.
b) Will lower the durability and life cycles of
product due to adding more function.
c) Increase the weight of the product since
additional power source such as Battery
cell is added
d) The overall shape do not convenience and
not portable.
70. 66
Appendix F1
I) Functional Structure of product
Press to fit
Adjust to fix
with object
Reach to the
object
Lock to the
location
Hold the body
tightly
Rotate Reverse
rotation
Reverse
mechanism
Hock
Lift
Release object
Pull out clipper
from body Release to clamp Un-clamp
Retract
Pull out
directly
Pull out
directly
Hand
Force
Situations
Reach to the
object
Apply force to
open clipper
After used
Sound, energy
Object
Sound,
energy
71. 67
Appendix F2
II) Cluster the Elements into Module Chunks
Press to fit
Adjust to fix
with object
Reach to the
object
Lock to the
location
Hold the body
tightly
Rotate Reverse
rotation
Reverse
mechanism
Hock
Lift
Release object
Pull out clipper
from body Release to clamp Un-clamp
Retract
Pull out
directly
Pull out
directly
Hand
Force
Cross head
Adjustable head
Handle
Hook
Sound, energy
Object
Sound
energy Reach to the
object
Apply force to
open clipper
Gripper
Situations
72. 68
Appendix F3
III) Rough Geometric Layout
(1) Components hierarchy
Arthritis tool
Handle
Adjustable
head
Cross
head
Clipper Hook
Upper
LowerGripping
tooth
Belt
Rubber
Rubber
Button
Rubber
Upper
h lf
Lower
Button
Pin
Spring
Interaction between chunks
Interaction within chunks
73. 69
Appendix F3
(2) Geometric Layout
Handle
Cross head
Rubber
Adjustable headButtons
Clipper
Front view
Front view
Side view
Gripping
tooth
74. 70
Appendix F4
IV) Incidental Interactions
Environment
Handle
Clipper
Hook
Cross
head
Adjustable
head
Bending,
Environment
Vibration
Environment
Stress concentration
Unbalance
force
75. 71
Appendix G1
Part
function
Mode of
failure
Cause of
failure
Effects of
failure (S) (O) (D)
Risk of
Priority
(RPN)
Detection
method
Correction
action
New
(S)
New
(O)
New
(D)
New
(RPN)
Picking
object
-Hook
does not
attach to
object and
not fitted.
-The hook
is
slagging.
-Unable to
hang
object.
-Improper
thickness at
the tip of
hook.
-Heavy load.
-Length of
curve at hook
is short.
-Unable to
picking
object.
-Fracture or
failure of
hook.
-The object
easy to slip.
6
4
5
5
4
4
7
6
9
210
96
180
-Difficulty in
attach object
to the hook.
-The shape of
hook slightly
deformed.
-Inspection at
the hook
-Use better
material that
not effected
by large force
apply.
-Use high
robust
material.
-Improve the
design
3
2
4
4
2
3
7
6
9
84
24
108
Clipping
object
-The end
of clipper
unable to
open and
close.
-The
clipper
stuck.
- Hard to
clip the
object.
-Malfunction
Of spring at
the clipper.
- Failure of
push button
mechanism.
- Worn out of
clipper teeth
and
alignment.
-Unable to
clip the
object.
-The clipper
unable in
and out.
-Improper
to clipping
object.
5
6
3
3
8
2
7
6
5
105
288
30
-Inspection
and remove
the clipper
from gripper.
-The clipper
does not
function.
-Difficulty to
clipping.
-Replace with
standard new
clipper.
-Find the
source of
failure and
try to adjust
if possible.
-Replace with
new clipper.
4
5
3
2
5
1
7
6
5
56
150
15
76. 72
Appendix G2
Part
function
Mode of
failure
Cause of
failure
Effects of
failure (S) (O) (D)
Risk of
Priority
(RPN)
Detection
method
Correction
action
New
(S)
New
(O)
New
(D)
New
(RPN)
Gripping
Object
-Gripper
does not
attach
smoothly.
-Unable
to retract
and
expand.
-Unable
grip for
object
that
slippery
and tight.
- Teeth
broken or
worn out.
- Failure of
push button
and the
mechanism.
-Unsuitable
force and
torque applied
-Object
does not
grip
safely.
-Unable
to adjust
with
different
size.
-Fracture
or broken
and
damage
the object
6
6
7
5
7
6
6
4
8
180
168
336
-Inspection to
the gripper.
-No changes
When press.
-Difficulty to
rotate and
pull.
-Replace the
renewable
teeth.
-Use better
material for the
mechanism.
-Apply the
sufficient and
try to minimize
force and
torque initially.
5
5
5
5
6
4
6
4
8
150
120
160
Opening
Water
Tab
-Unable
to open
the water
tab that
too tight
-Unable
to attach
or fitted
object
smoothly
-Unsuitable
force and
torque
applied.
-Unsuitable
press applied.
-Fracture
or
broken.
- Object
does not
open
safely.
5
6
6
4
8
5
240
120
-The opening
water tab
hard to adjust
and control.
- Inspection
to the
attached part
- Avoid using
at tight water
tab and more
suitable use for
plastic material
water tab.
-Apply
sufficient
amount of
force when
press to fit the
head and tab.
4
5
5
2
8
5
160
50
83. 79
Appendix I
Polyamides (Nylons, PA)
i. Composition
(NH(CH2)5C0)n
ii. Caption
Polyamides are tough, and easily colored.
iii. General properties
Density 1120 - 1140 kg/m^3
Price 13.8 - 15.18 MYR/kg
iv. Mechanical properties
Young's Modulus 2.62 - 3.2 GPa
Shear Modulus *0.9704 - 1.185 GPa
Bulk modulus 3.7 - 3.9 GPa
Poisson's Ratio 0.34 - 0.36
Hardness - Vickers 25.8 - 28.4 HV
Elastic Limit 50 - 94.8 MPa
Tensile Strength 90 - 165 MPa
Compressive Strength 55 - 104.3 MPa
Elongation 30 - 100 %
Endurance Limit *36 - 66 MPa
Fracture Toughness *2.218 - 5.617 MPa.m^1/2
Loss Coefficient *0.0125 - 0.01527
v. Thermal properties
Thermal conductor or insulator? Good insulator
Thermal Conductivity 0.233 - 0.253 W/m.K
Thermal Expansion 144 - 149.4 £gstrain/¢XC
Specific Heat *1601 - 1665 J/kg.K
Melting Point 209.9 - 219.9 °C
Glass Temperature 43.85 - 55.85 °C
Maximum Service Temperature 72.85 - 86.85 °C
Minimum Service Temperature *-123.2 - -73.15 °C
vi. Impact on the environment
Nylons have no known toxic effects, although they are not entirely inert biologically.
Nylons are oil-derivatives, but this will not disadvantage them in the near future. With
refinements in polyolefin catalysis, nylons face stiff competition from less expensive
polymers.
84. 80
vii. Processability (Scale 1 = impractical to 5 = excellent)
Castability 1-2
Mouldability 4-5
Machinability 3-4
Weldability 5
viii. Durability
Flammability Average
Fresh Water Very Good
Sea Water Very Good
Weak Acid Good
Strong Acid Poor
Weak Alkalis Very Good
Strong Alkalis Good
Organic Solvents Average
UV Average
Oxidation at 500C Very Poor
ix. Supporting information
Design guidelines
Nylons are tough, strong and have a low coefficient of friction, with useful properties
over a wide range of temperature (-80 to +120 C). They are easy to injection mould,
machine and finish, can be thermally or ultrasonically bonded, or joined with epoxy,
phenol-formaldehyde or polyester adhesives. Certain grades of nylon can be electroplated
allowing metallisation, and most accept print well. A blend of PPO/Nylon is used in
fenders, exterior body parts. Nylon fibers are strong, tough, elastic and glossy, easily
spun into yarns or blended with other materials. Nylons absorb up to 4% water; to
prevent dimensional changes, they must be conditioned before molding, allowing them to
establishing equilibrium with normal atmospheric humidity. Nylons have poor resistance
to strong acids, oxidizing agents and solvents, particularly in transparent grades.
