Evaluation - Controlled Convergence vs. Weighting and Rating Weighting and Rating Matrix
• Produced our final concept • More logic and mathematical
calculation involved• Incorporates the users’
preferences in terms of features available
• Need to refer to PDS more than controlled convergence matrix
Controlled Convergence Matrix
• Narrowed down our choice of concepts
• Involved a lot of personal opinion
• Can achieve a better idea of performance compared to competitors
• Allows comparison against another product
Group Practical Logical Quick OutcomeYES PRACTICAL
COMPARISON
YES NO MORE IMPARTIAL
Group Practical Logical Quick Outcome YES PRACTICAL
COMPARISON
YES QUICKER THAN WEIGHTING AND RATING
COULD HAVE BEEN IMPROVED
Evaluation – Dot sticking • Quick and easy to use• More successful when used with
scamper and force fitting techniques to add or change features within concepts
• Allows for more creativity development within concept evaluation
• All based on personal opinion – risk of ‘following the crowd’ and pushing through of ideas
Group Practical Logical Quick Outcome YES and NO
PRACTICAL and THEORY
NO YES PERSONAL OPINION
Design for Safety and Reliability - FMEA Part Function Potential Failure Mode Potential Effects of Failure Mode
Severity Potential Causes of Failure
Occurrence Detection Prevention
Detection RPN Actions
Ear CoversProvides a means of playing music to be heard by the user Hearing damage caused by loud music Causes permanent hearing loss in user 8
The need to play music at a very loud level 3 NONE DESIGN MARGIN 7 168
Have a warning when music is at damaging levels - constant beeping
Plastic covering snaps/cracks Cuts user's finger, speakers stop working 4Bad material choice, insufficient material strength 5 VISUAL INSPECTION DESIGN MARGIN 6 120
Use strong, thermosetting plastic
Speakers stop working correctly Headphones become useless 3 Bad design 7BAD QUALITY DURING USE TESTING 9 189 Buy-in high quality speakers
Noise flip switch sticks Headphones become useless 3 Wear, repetitive use 3 NONETESTING, DESIGNED PREVENTION 5 45
Connection to headband snaps Cuts user, headphones become useless 4Bad material choice, insufficient material strength 2 NONE DESIGN MARGIN 7 56
Padding becomes loose and becomes lodged in the ear Causes temporary/permanent damage to the ear 6
Bad material choice, manufacturing mistake 8 VISUAL INSPECTION TESTING 8 384 Put a cover over the padding
Connection between covers and headband is no longer tight and simply falls out Headphones become useless 3 Wear, repetitive use 6 INSPECTION TESTING 4 72
A young child chokes on padding Child stops breathing temporarily, causes death 10Bad material choice, manufacturing mistake 3 NONE
DESIGN, MATERIAL CHOICE 10 300
Place a cover over the padding
Telescopic headbandSecures the headphones to the head of the user Padding falls off
Headphones don't make secure connection with head 2 Manufacturing mistake 7 VISUAL INSPECTION TESTING 7 98
Sliding mechanism sticks Headphones will no longer be compact 1 Wear, repetitive use 3 INSPECTION TESTING 4 12
Surface becomes scratched and cracked Looks bad, causes small injury, collects germs 4Bad material choice, insufficient design for use 2 VISUAL INSPECTION DESIGN MARGIN 5 40
A small child's finger becomes trapped in sliding mechanism Causes injury, causes loss of finger 8 Bad design 2 NONE DESIGN MARGIN 10 160
No physical gap between sliding parts
Hair becomes trapped in sliding mechanism Causes pain 5
Bad design, telescopic fails to lock in place 6 NONE DESIGN MARGIN 10 300
No physical gap between sliding parts
Spring wireProvides a connection between the headphones and the audio device Wire snaps Headphones become useless 3 Defect in wire 8 VISUAL INSPECTION
TESTING, DESIGN MARGIN 7 168 Buy-in high quality wire
Person wraps wire around their fingerReduces blood flow in finger, causes loss of finger 8 Incorrect use of product 7 NONE
DESIGN, MATERIAL CHOICE 10 560
Warn of incorrect use on packaging
Wire gets caught around neck while cycling Results in strangulation, causes death 10 Wire is too long 3 NONE DESIGN 10 300 Reduce the length of the wire
Wire gets tangled on the seat belt in a car
User also becomes tangled, could cause strangulation 10 Wire is too long 3 NONE
DESIGN, MATERIAL CHOICE 10 300 Reduce the length of the wire
Wire snaps at volume control Headphones become useless 3 Defect in wire 8 VISUAL INSPECTIONTESTING, DESIGN MARGIN 6 144 Buy-in high quality wire
Jack and MP3 connection Connects the wire to the audio deviceWire snaps at connection between wire and jack Headphones become useless 3 Defect in wire, insufficient strength 8 VISUAL INSPECTION
TESTING, DESIGN MARGIN 4 96
Connection between jack and audio device snaps
Headphones become useless, audio device also gets broken 4 Defect 2 VISUAL INSPECTION TESTING 7 56
Jack and MP3 become water logged Could cause small electric shock 8Bad design, insufficient protection from water 3 NONE DESIGN 8 192 Provide a waterproof cover
• A good overview of problems which may occur when the product is being used by its intended end user, does not give any detail about problems which may occur during the manufacturing or design process
• Highlights areas which may have been otherwise neglected
• Needs expertise to identify the current detection/prevention which is being implemented
• Can be completed more quickly if one person carries out the task instead of a group discussion
• Surprisingly good tool for innovation and creativity
Ear Covers
Provides a means of playing music to be heard by the user
Hearing damage caused by loud music
Causes permanent hearing loss in user 8
The need to play music at a very loud level 3NONE
DESIGN MARGIN 7
168
Have a warning when music is at damaging levels - constant beeping
Plastic covering snaps/cracks
Cuts user's finger, speakers stop working 4
Bad material choice, insufficient material strength 5
VISUAL INSPECTION
DESIGN MARGIN 6
120
Use strong, thermosetting plastic
Group Practical Logical Quick Outcome YES and NO
THEORY NO NO TOP-LEVEL OVERVIEW
Design for Safety and Reliability – Root Cause Analysis• Produces a very thorough overview of one problem
• Would be beneficial to the design process if every problem highlighted in the FMEA chart was analised like this
• Takes a very long time to complete
• Outcome could have been improved if experts from each major category had collaborated to produce the diagram – would have delivered a more knowledgible, accurate outcome.
Group Practical Logical Quick Outcome NO RESEARCH
and THEORY
YES NO OPPORTUNITY TO BE IMPROVED
Design for Manufacture and Assembly - Value Analysis vs. Value Engineering
Value Analysis• Develops thoughts of
manufacture and assembly during the design stage
• Could be used as a comparative with existing products as a form of evaluation
• More visual output, easier to use
• Takes a while to complete, finding costs can be difficult and can incur errors
Value Engineering• Takes the innovative design
ideas and makes them achievable – thoughts and ideas on how the product will fit together
• More robust design achieved because thought is given to components and parts
Group Practical Logical Quick Outcome NO RESEARCH
and THEORY
YES NO VALUABLE INFORMATION
Group Practical Logical Quick Outcome YES IDEA
GENERATION
NO QUICKER THAN VALUE ANALYSIS
COULD HAVE BEEN IMPROVED
Design for Manufacture and Assembly
Group Practical Logical
Quick Outcome
YES RESEARCH and IMPLEMENTATION
YES NO GOOD VISUAL AID FOR WHAT HAD BEEN ACHIEVED THROUGH VA AND VE
End of life Product Strategy – General DFE guidelines vs. Life Cycle Analysis
• Still leaves room for innovation, however results can be very similar
• Can take a long time to complete
• Driven by goals set by the designer – ensure the goals of the project are achieved
• Can be repetitive
• Usually produced the same results as DFE guidelines process
• Good to take a different viewpoint and concentrate on the environment instead of basing everything purely on users’ needs
• Takes a long time to process• Produces a very inclusive
product
Group Practical Logical Quick Outcome Better for continuity if it is done individually
IDEA GENERATION and RESEARCH
YES NO REPETITIVE, POINTS FOR PDS
Group Practical Logical Quick Outcome Better for continuity if it is done individually
IDEA GENERATION and RESEARCH
YES NO REPETITIVE, VISUAL
End of Life Product Strategy - Outcomes
• Outcome – made the concept more recyclable, achieved at the concept stage by using different materials and making it easier to assemble.
• Makes the entire disposal stage easier and ensures this stage is incorporated in the design from the beginning
• The graphs shows the impacts of the product at different stages during the design process.
• Regular weekly meetings on a Tuesday afternoon
• Extra meetings when required• ‘TO DO LIST’ – shared amongst group• Deadlines for method/task completion
emailed to members• Use of Facebook and email to share
information
Project Management