Creative Engineering Designg g gModule 8: Conceptual Design: Morphological Method,
Problem Reformulation, Ideal Design, Examples
Centre for Product Design and ManufacturingIndian Institute of Science, Bangalore, India
Amaresh Chakrabarti
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Outline and ModulesModule Topic No of hrsModule Topic No of hrs
1 Introduction: design Thinking across domains, major elements of design thinking, definition of system, design, product design, engineering design, creativity, science, design science (research); Importance of design
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design science (research); Importance of design2 Product life cycle, Structure of systematic product design process, Structure of
systematic product development process, Importance of systematic design, , Case Study4
3 Task Clarification1: overall process and steps, market study, user/habitat analysis using 4role play, observations and interaction with stakeholders
4 Task Clarification 2: Problem identification using requirement checklists, study of products and patents using Innovation Situation Questionnaire (ISQ), steps for collating data from multiple sources into a stakeholder requirement list translating stakeholder
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data from multiple sources into a stakeholder requirement list, translating stakeholder requirements into technical requirements, assigning importance to requirements
5 Task Clarification 3: Problem definition to develop solution neutral problem statements,problem analysis to develop input‐output transformation, case study
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6 Introduction to conceptual design: Identification of functions, Ideation, Consolidation into solution proposals (Concepts), and their systematic evaluation for selection of the most promising concept. Details of function structure generation and brainstorming
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7 Conceptual design 2: Details of Synectics method, Trigger Word technique, Checklist 47 Conceptual design 2: Details of Synectics method, Trigger Word technique, Checklist method, Examples
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8 Conceptual design 3: Consolidation of ideas into concepts, e.g. with Morphological charts. Use of TRIZ Contradiction or ideality to identify and resolve issues with concepts
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l d h d f l l l l d h l9 Conceptual design 4: Methods for simulation: analytical, virtual and physical simulations, for evaluation or improvement.
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10 Comparative evaluation and selection of concepts: ordinal and cardinal methods 4TOTAL 42
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Overview of Module 8
Consolidation of ideas into concepts• Consolidation of ideas into concepts
• Morphological Methodp g
• TRIZ methods
• Problem Reformulation method
• Ideality method• Ideality method
• Examplesp
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Main Stages of the Design ProcessMain Stages of the Design ProcessInput/OutputActivity
SOCIETAL NEED(OR IDEA)
REQUIREMENTS
TASKCLARIFICATION
CONCEPT
CONCEPTUALDESIGN
EMBODIMENTDESIGN
LAYOUT
PRODUCTION
LAYOUT
DETAILDESIGN
PRODUCTIONINSTRUCTIONS
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Conceptual Design…• Purpose: Starting with outcomes from task clarification, develop a set of concepts, and select the most promising conceptp , p g p
• Steps:• Develop function structures – Starting from the requirements list, overall I/O of the
Focus of this module
Develop function structures Starting from the requirements list, overall I/O of the product, and SNPS, develop product and process function structures of the intended product• Develop ideas for each function and associated problems – Use one or more of the ideation techniques (brainstorming, Synectics, Trigger word, Checklist, etc.) to generate q ( g y gg ) gmultiple, alternative ideas to fulfil each function• Combine ideas into concepts – Combine ideas into concepts (e.g. using morphological matrix) where each distinct concept satisfies at least one function using a distinct idea than do any other concepts• Consolidate concepts – Identify problems with how well each concept is likely to satisfy the functions and other requirements from the requirements list (e.g. by identifying contradictions, simulating various aspects of each concept etc) and resolve these issues (using TRIZ principles andsimulating various aspects of each concept, etc), and resolve these issues (using TRIZ principles and other creativity approaches such as brainstorming, Synectics etc.)• Evaluate concepts and select the most promising – Use appropriate portions of the requirements list to evaluate all concepts, and select the best for further developmentrequirements list to evaluate all concepts, and select the best for further development
• Outcome: A set of concepts and a selected concept 5
Techniques for Idea Generation
• To help make search for ideas more efficient• Brainstorming• Synectics• Synectics• Trigger Word Technique• Checklist Technique•Morphological Technique•Morphological Technique• Interaction Matrix Technique• Analysis of Interconnected Decision Areas
(AIDA)
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Morphological Method (from Pahl and Beitz, 2007)p g
• The morphological method helps find allth ti ll ibl l ti t bltheoretically possible solutions to a problem
• First the elements that are essential to all solutions, ,called ‘parameters’, are found
• Then an inventory is made of possible realizations• Then an inventory is made of possible realizations of each element, the ‘components’ or ‘ideas’
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Morphological Method…• Problem: Design a manual propulsion system for a small boat
Designparameters
Alternative ideas
Input rotating oscillating reciprocatingInput motion
rotating oscillating reciprocating
Input one Both One foot Both feet Hand source hand hands &footInput device
Hand crank
pedals lever treadmilldevice crankOutput device
fin screw propeller Paddle wheel
jet
mechanism gears Belt pulley
Chain & sprocket
linkage pump
O i i di li i k liOperator position
sitting standing reclining kneeling
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Morphological Method…p g
• Morphological approach strictly separates between creating and evaluating ideas
• ‘Detachment from prejudice is an essentialDetachment from prejudice is an essential requirement of the morphologist’, said Zwicky, the inventor of the methodinventor of the method
• Zwicky described this method as follows:
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Morphological Method…
St 1 F l t th bl t b l d t l
p g
• Step 1: Formulate the problem to be solved as accurately as possible
• Step 2: Identify and characterise all parameters that mightStep 2: Identify and characterise all parameters that might occur in the solution
• Step 3: Construct a morphological chart or multidimensional p p gmatrix, which contains all solutions to the problem
• Step 4: Analyse all solutions carefully and evaluate against the objectivesobjectives
• Step 5: Select and implement the best solutions, in so far as the means are availablethe means are available– practical application may require another morphological study.
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Morphological Method…
• Zwicky used morphological method to discovered new
p g
Zwicky used morphological method to discovered new principles for jet engines and studied the existence of celestial bodies not yet discovered
• Morphological box method is also used as a forecasting technique
• In engineering design the morphological method is one of• In engineering design, the morphological method is one of the most powerful heuristics to generate new solutions
• Exhaustive following of Zwicky’s procedure leads toExhaustive following of Zwicky s procedure leads to completeness– but at the cost of an enormous amount of analysis and evaluation
• In practice morphological method is applied less stringently, since using an incomplete analysis, good – and sometimes even the best – solutions can be generatedeven the best solutions can be generated
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Morphological Chart
• A morphological chart consists of parameters and
p g
p g pcomponents (or ideas)
• The parameters describe the characteristics or functions pwhich a product or process should have or fulfill– what the object should be or have
• The components are the means by which the parameters may be realized
• Parameters are abstract and general– little or no reference is made to material features
• Each parameter indicates a category of similar objects or process
• The components are concrete and specific– specify the elements which pertain to that category 12
Morphological Method: Problemsp g
• The morphological method faces three types of problems • The parameters should be “independent”
– the choice for a component for one parameter should not limit the options for the other parameters
– e.g. in the morphology of screws, apart from length, diameter and type of material, cost price should not be taken as a parameter, since it depends on the decisions on the first three parameterssince it depends on the decisions on the first three parameters
• It is often difficult to find independent parameters• The chart may then give incompatible solutions that have toThe chart may then give incompatible solutions that have to be detected and eliminated
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Morphological Method: Problems…p g
• The second problem is identifying the ‘essential’ parametersth t th t f ll l ti– the parameters that are common for all solutions
• The morphological method does not offer any help in this dregard
• Insight in the field of possible solutions plays a significant role– domain knowledge is often indispensable to achieve good results
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Morphological Method: Problems…p g
• The number of alternative solutions contained in the chart rapidly increases with the no. of parameters and componentsrapidly increases with the no. of parameters and components
• A 10 x 10 chart theoretically contains 10^10 solutions, for which it is Impossible to work out and evaluate all solutionswhich it is Impossible to work out and evaluate all solutions– Even if an alternative takes 1 min. and one works 40 hrs/wk, needs 10^10 minutes = 4 x 10^6 weeks = 80000 man‐ years!needs 10 10 minutes 4 x 10 6 weeks 80000 man years!
• The method needs an evaluation strategy that dramatically limits the no of solutions to be evaluatedlimits the no. of solutions to be evaluated
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TRIZ/TIPS: Theory of inventive problem solving( d t d i il f T i k t l 1998)(adapted primarily from Terninko et al., 1998)
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TRIZ
creativity
age
adult child TRIZ• fears contradiction • not sensitive to contradiction • searches for contradictionfears contradiction• keeps things separate• uses unorganized deduction
not sensitive to contradiction• connects all with all• deduces specific from specific• substitutes problem(P) if failed
• connects all possible• deduces by analogy• substitutes P purposefully
• gives up solution if failedp ( ) p p y
Adult: knowledge without flexibilityChild: flexibility without knowledgeChild: flexibility without knowledgeCreative: purposeful, flexible knowledge
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TRIZ• Assumptions
– Contradictions help solve problems– Ideal design is the goal– Generic knowledge of P solved in past can be used to solve current P
• Levels of innovation (from patent analysis)• Levels of innovation (from patent analysis)– 1: solution by methods well‐known in the specialty of inventor (32%)
– Increase thickness of wall for better insulation (module level few trials)Increase thickness of wall for better insulation (module level, few trials)– 2: Compromise improvement of an existing system within area (45%)
– Adjustable steering column (system level, few hundred trials)– 3: Essential impr, existing system, known tech other disciplines (18%)
– Clutch on electric drill (system level, few thousand trials)– 4: Invention outside technology, little known physical effects (4%)gy, p y ( )
– Cleaning burrs using cavitations; shape metal key (tens of thousand)– 5 Major discovery requiring new science (1%)
Lasers transistors (million trials)– Lasers, transistors (million trials)
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electro magneticchemical
personperson
company
i dindustry
societysociety
Majority of patents within
mechanical thermo dynamicuniverse
Majority of patents within• mechanical• electro magnetic• chemicalchemical• thermodynamic
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Inventive P, psychological inertiap y g
• Inventive P (problems)• Inventive P (problems)– Have contradictions inherent in the problems– Inventive problem solver eliminates the contradictions– Reduce psychological inertia– Rest of designing is to make the solution embodiable etc
h l l• Psychological inertia– Tendency to go in directions familiar (car key syndrome)
T d t i di ti f l– Tendency to go in directions successful
S P
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electro magneticchemical
S PS P
mechanical thermo dynamic
• Team composition and team work could help• But still does not solve misdirected search• knowledge required is to eliminate contradictionsknowledge required is to eliminate contradictions
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TRIZ techniquesq
• Innovation situation questionnaire (ISQ): data collection
bl f l k d l• Problem reformulation: making contradictions explicit
• Resolving contradictions: solving problemg g p
• Striving for Ideal design: solving problem
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ISQ• Features
– Helps reformulation and decomposition of the problem– Use generic terms, record solutions generated during this
• Information about system to be improved; its environment• Name: (if exists):
• screw and screwdriver• Primary function (use active verb, object and constraint)y ( j )
• Screw holds bones surfaces in position during healing• Structure (current / desired): at static state plus drawings
• hollow shank head Allen wrench hole Allen wrench• hollow shank, head, Allen wrench hole, Allen wrench• Functioning (behaviour): how it works to do primary function
• Screwdriver placed in the hole in screw‐head, turned in to place• Screw cuts into the bones, and holds them together• For removal, first tighten the screw to break the connection• Then slowly turn it outThen slowly turn it out
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Problem reformulation• Construct a simple cause‐effect graph
Li k b t th i d b k d th i f ti• Linkage between the primary drawback and the primary function• Harmful function (HF): drawback• Useful function (UF): function
• Steps• Use specific phrases describing HF<‐>UF interactions (next slide)
h h ( ) ( )• Begin with either primary UF (PUF) or primary HF (PHF)• Try to find functions that can be linked to the other (PUF‐> PHF)• Linkage complete when at least on path found between PHF & PUF• And all related secondary problems• Analyse graph to identify possible task statements
B fit• Benefits• Useful image of many interrelated smaller problems included in P• You need to eliminate PHF, you need to work on some of these, y
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Problem reformulation• Three basic phrases
• UFn causes HFnUFn causes HFn• UFn is used to eliminate| HFn• UFn required for UFn+1 ;UFn+1 requires UFn; UFn provides UFn+
• Four questions for useful functions (use ISQ info)• Is this UF required for another UF? UFn required for UFn+1• Does this UF cause any HF? UFn causes HFn• Does this UF cause any HF? UFn causes HFn• Is this UF to eliminate a HF? UFn is used to eliminate| HFn• Does this UF require for another UF? UFn‐1 required for UFn
• Four questions for useful functions• Does this HF cause another HF? HFn causes HFn+1
I thi HF d b th HF? HF 1 HF• Is this HF caused by another HF? HFn‐1 causes HFn• Is there a UF to eliminate this HF? UFn is used to eliminate| HFn• Is this HF caused by a UF? UFn causes HFn
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Problem reformulation• Screw removal problem
• A crack formed in the neck joining the leg femur to the ball. The crack was h h h d f h k d bthrough the narrowest diameter of the neck. It was caused by impact directed upward toward the ball from lower right corner of figure. The screw with washer was removed after one year. The head of the other
t t i d d l ft i l L i th t t blscrew got stripped, and was left in place. Leaving the screw not acceptable.
• Desired improvement is removal of the remaining screw• PHF is: screw cannot turn outPHF is: screw cannot turn out
• Four questions for useful functions• Is this HF caused by another HF? Screwdriver slips in slot• Is this HF caused by another HF? Slot is rounded• Is this HF caused by a UF? Large frictional force • Is this UF required for another UF? Screw integrated into bone• Is this UF required for another UF? Screw integrated into bone• Does this UF cause any HF? Screwdriver slips in slot• Is this UF provided by another UF? Bone growth around shaft• Is this UF required for another UF? Heal crack in bone and fill hole
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Screw does ScrewdriverSlot is causes
not turn outslipsrounded
Large f i i l
Screw i d
Requiredf
Heal bone Bone growthRequiredf frictional
forceintegrated into bone
forand fill holeg
around shaftfor
• Find a way to prevent a HF• Find a way to prevent a HF• Find an alternative of a UF• benefit from a HF• Enhancement of a UF• Enhancement of a UF• Resolution of a contradiction (retain good effect, eliminate bad)
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Screw does not turn out
Screwdriverslips
Slot is rounded
causes
not turn outslipsrounded
Large frictional
Screw integrated
Requiredfor
Heal crack d fill h l
Bone growthd h ft
Requiredfor
forceg
into boneforand fill hole around shaftfor
• Way to enhance (heal crack and fill hole)Way to enhance (heal crack and fill hole)• Alternative way to (heal crack…) that doesn’t require (bone growth…)• Way to enhance (bone growth…)• Alternative way to (bone growth…) that doesn’t provide (large frictional…) but provides y ( g ) p ( g ) p(heal crack…) => soften bone, lubricate• Way to enhance (large frictional…)• Alternative way to provide (large frictional…) that provides (screw integrated…) but y p ( g ) p ( g )does not cause [screwdriver slips in slot] and does not require (bone growth…)• (large frictional…) to provide (screw integrated…), not cause [screwdriver slips…]=> dissolve screw, dissolve threads, reduce dimension of screw• Way to benefit from [slot is rounded] => easy‐out left‐handed screw• Prevent [slot is rounded] under condition (large frictional…) => use glue
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Contradiction• When to use
– If your problem fits into the parameters in tables given– If it matches with one of the contradictions given
• Contradictions• Technical: known alternatives improve one aspect worsen another• Technical: known alternatives improve one aspect, worsen another
• Making a container stronger makes it also heavier (analyse existing D)• Physical: if some aspect of a product must have two opposing states
• Car small for city driving, but large for comfort (requirements conflict)• Physical <‐> technical
• Structuring a problem as a contradiction• Structuring a problem as a contradiction• Use ISQ and problem reformulation: UFC provides UFA, causes HFB
• Find alternative way of (C) that provides/enhances (A), not cause [B]• Find a way to eliminate/reduce/prevent [B] under the condition (C)• Alternative way to provide (A) that does not require (C)
• (Large frictional ) required for (Screw integrated ) causes (screwdriver )• (Large frictional…) required for (Screw integrated…), causes (screwdriver…)• (Large frictional…) should provide (Screw …), not cause (screwdriver…)
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Ideal designg• When to use
l ( h k f f b lb f l h l )– Always! (Shock proof cover for bulbs for lunar vehicle)
• Ideal design: Ideality = all useful effects/all harmful effects• Provides the desired function without existing• Provides the desired function without existing• Function performed by already existing resources
• NASA, Architecture• State the final result and back away as little as possible
• Using the concept of ideal design• Accept current design• Accept current design• Increase numerator by adding/improving functions• Remove unnecessary F/ combine subsystems of F to reduce denominator• Increase numerator at a faster rate than denominator
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Ideal design: exampleg p
– Comparing resistance of different alloys to an acid– Several alloy specimens placed in a closed, acid‐filled container– After certain time container opened and effect of acid measured– But acid damages the container walls => can be coated => costly
• Ideal design: exposing acid without requiring container?• Ideal design: exposing acid without requiring container?• To keep the specimen in contact with the acid without a container• Look for resources available: specimen, air, gravity, adhesion etc.
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Ideal design: Approachesg pp• Two general approaches
– Use of resources: including waste: Thermopane windows, sound bafflesUse of resources: including waste: Thermopane windows, sound baffles– Use of effects: physical, chemical, etc: reinforcing rods, split granite
• Six specific approaches• Exclude auxiliary functions: Paint without solvents (dangerous fumes): use
field to coat metal with powder paint, heat metal and powder melts• Exclude elements: delegate their functions to resources/effectsg /• Identify self‐service: look for aux F fulfilled along with primary F: • Find Turning heavy rotors during transport (shocks cause bearings to
create hollows expensive to turn periodically with engines) Turn usingcreate hollows, expensive to turn periodically with engines). Turn using shocks.
• Replace elements, parts or total system: complex‐>simple, copyCh i i l f i i lif h• Change principle of operation to simplify the system
• Keeping soft glass flat while making is hard as hot soft sheet glass tends to sag between rollers as sheet moves on conveyor. Ideal: no sagging: if rollers were smaller, ideally molecules everywhere: pool of molten tin to convey.
• Utilise resources: Exhaust gas from excavators filtered thru the excavated34
Ideal design: stepsg p
St 1 d ib th it ti t i• Step1: describe the situation to improve • Step 2: Describe the ideal situationp• Step3: Think of how this could be realised
If fi i h• If yes, finish• If yes but with drawback, resolve contradiction• If no, make it less ideal and try
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OVERVIEW
• Alarm clock• ISQ• Problem reformulation• Primary useful and harmful functions• Inter-relationship between the functions• Contradiction• Ideal design• Design solutions through brainstorming
• Shaving razorf• Problem reformulation
• Primary useful and harmful functions• Inter-relationship between the functions
C t di ti• Contradiction• Ideal design• Design solutions through brainstorming
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Name:
Information about system to be improved; its environment
Name:• Primary function (use active verb, object and constraint)
• alarm clock to use sound to interrupt the sleep of a person at the desired time.
• Structure (current / desired): at static state plus drawings• Time-measuring and display device (clock), time deferring g p y ( ), g
device, sound generating device ( speakers), alarm setting system, alarm indication system.
• Functioning (behaviour): how it works to do primary functiong ( ) p y1. Setting the time.2. Setting the alarm time.3 P t l3. Person goes to sleep.4. At the alarm time, the internal system of the clock triggers off
the sound generating device to emit sound.5. Person wakes up partially, activates the time deferring system
(snooze function) and goes back to sleep.6. After the set snooze set time is over, go to step 4 then to step 7.7. Person wakes up fully from sleep, deactivates the alarm setting
system. 40
Available resources: free resources available for use
• how it (should) interact with super-system of which it is a part• Create sound to interrupt sleep is a part of changing theCreate sound to interrupt sleep is a part of changing the
state of human mind. • With any other system with which it interacts.
Aural senses and human touch• Aural senses and human touch.• With any other system located in close proximity with which it
interacts indirectly.• Neural network and human touch.
• Natural system surrounding it• Needs to be above the ambient decibel level and below
the level that disturbs persons other than the subject (s).
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Available resources: free resources available for use
• Substance: materials• Air, skin, plastic, metal, glass, quartz, human body, moisture.
• Field: energy/actions• Surrounding air, light, sound, temperature, triggering signal,
Chemical energy of the battery, electric field, spring force, gy y, , p g ,body temperature.
• Functional: what functions are available already• A substantial input to any of the human senses will result inA substantial input to any of the human senses will result in
interruption of sleep.• Informational: what information is available
S t ti i di ti f ti d l• Set-time, indication of time and alarm.• Time: What time is available
• Time required to set ,count-down for alarm, ringing time, snooze, simultaneous countdown and timing.
• Space: What space is available• Nesting (Space to keep the alarm clock), space within theNesting (Space to keep the alarm clock), space within the
outer casing, sweep envelope for human hand.42
Information about the problem situation
• Drawbacks to eliminate or desired improvementsp• Ringing volume is not enough to interrupt the sleep.• No option for volume control (should travel through hindering
media like pillows blankets etc )media like pillows, blankets, etc.).• Disturbs your sleep but does not wake up.• Disturbance to others who might not need to wake up.• Absence of the alarm indicator. • No alarming time greater than 12/24 hours can be set.• Just one alarm can be set at a time.• No option for a weekly alarm system.• Final decision of waking up is not controlled by the system
(option of multiple snoozing provides for not waking up)(option of multiple snoozing provides for not waking up).• Volume level of the alarm is not adaptive to ambient sound
levels.
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Information about the problem situation
• Mechanism which causes the drawback to occur, if it is clear• No volume control device (potentiometer, etc.) in alarm
controls.• Media in between reducing the intended alarm volume• Media in between reducing the intended alarm volume
(pillows, quilts, etc.)• The clock is itself a 12/24 hour system, so cannot put alarm
for more than 12/24 hours respectivelyfor more than 12/24 hours respectively.• Easy switching off and snoozing disturb the sleep but not
wake up.N li d l t• No personalized alarm system.
• No provision for date setting.• No feedback from the environment about the required q
decibel level.• Aural sensation alone is not sufficient to wake a person up.• Multiple parallel processing required to have multipleMultiple parallel processing required to have multiple
alarms.• Alarm volume reduces the battery power. 44
Information about the problem situation
• Other problems to be solved: modify direction of development?• Affecting multiple senses (water sprinkling, bright light, etc. )g p ( p g, g g , )• Induce physical/mental activity in the subject to wake him/her
up (treadmill, noises etc) .• Make the switching off the alarm clock difficult (password• Make the switching off the alarm clock difficult (password,
etc.).• Biologically/ psychologically controlling the sleeping/waking
sensationsensation.• Feedback about the slumber state/ degree of sleepiness of the
subject.
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Changing the System
• Allowable changes: complete/major/small changes and why• Multiple features be provided in the system like password, multipleMultiple features be provided in the system like password, multiple
alarms, date setting, repetitive alarm.• Activation of multiple senses is possible.• Feedback from the ambient environment• Feedback from the ambient environment.• Using alternate energy source or back-ups to maintain the alarm level
at all time.S i hi ff b d diffi l• Switching off system can be made difficult to operate.
• Limitations to changing the system: what can/not be changed• The biological system of the body is best left undisturbed.e b o og ca syste o t e body s best e t u d stu bed• Cost is a constraint when applying new technologies.• Should still remain handy.
B tibl ith th• Be compatible with the energy source.• Should be simple and easy to use.
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Criteria for selection of solution concepts
• Desired technological • Expected degree of noveltycharacteristics• User interface.• Optimum energy to drive the
• Unexpected but desired features.
• Multiple features along withOptimum energy to drive the system.
• Ease of manufacturability.• Desired economic characteristics
Multiple features along with the alarm.
• Likelihood of getting a patent.• Desired economic characteristics
• Cost incurred.• Quick to set and use.
patent.• Other criteria
• Effectiveness of the system in waking a person up• Space economy.
• Desired timetable• Use of available and simple
in waking a person up.• Adaptability to the
environment.Use of available and simple technologies.
• Avoid systems that might use lengthy research processes.
• Modularity of feature attachments.
lengthy research processes.
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Problem reformulation
• Waking up problem• Waking up problem• A person validates the current time and sets up the alarm time.
At the set time, the system triggers off the ringer and a sound is t d th t i t t th l f th Hgenerated that interrupts the sleep of the person. However,
many a times, the alarm is very conveniently avoided or switched off and sleep is continued. Hence the primary purpose is defeatedis defeated.
• PUF: Reliable waking up of a person comfortably.• PHF : Alarm does not wake a person up always.
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Signal not sent to hand
Validate time Switch off the snooze
Alarming deferredGo back to sleep
sent to hand
Indication of time
Time count going on
Setting the alarm with specific snooze time
Indication of time to wake up
Countdown of alarmDoes not
Energy source discharging
Timer stopsPHF: Alarm does not wakea person up always.
Alarm triggered at set time Sound at pre-set volumeLow volume
High volume
Does not disturb others
Other people are disturbed
Switched off by someone
PUF: Reliable waking up of a person comfortably. Switch off and wake up
Sound waves transmitted through the common medium of air
Interrupt sleepChange of medium leads to lowering of volume
someone other than the subject
Continuous aural sensation
Si l t t b iSignal sent by the brain to theD i i ki l ft t th b iSignal sent to brain the brain to the hand and the ear
Decision making left to the brain
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PHF : Alarm does not wake a person up always.
PUF: Reliable waking up of a person comfortably.
Useful functions: yHarmful functions:
1. Going back to sleep.
Useful functions:
1. Interruption of sleep.2 Alarm triggered at the right time 2. Too loud sound.
3. Medium dependent sensation.4. Low sound volume.
2. Alarm triggered at the right time.3. Induced physical and mental
activity.4 Setting and validation of time
5. Easy control over switching off / snooze option.
6. Decision making left to brain.
4. Setting and validation of time.5. Indication of time / waking up
time.6 Continuous time count going
7. Switched off by someone other than the desired subject.
8. Other people are disturbed.
6. Continuous time count going on.
7. Easy control over switching off / snooze option.
9. Switching off is dependent on physical body parts (movements).
10. Limited energy source.
snooze option.8. Signal sent through a common
medium through easy propagation.
11. Signal sent through a common medium and is medium dependent.
12. Pre-set volume.
p p g9. Signal sent to brain.10. Pre-set volume.
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Contradictions/Task StatementsAlternate way to:1. Interruption of sleep without allowing the person to go back to sleep.2 S f2. Signal amplified enough to wake up the person without disturbing
others.3. Use an easily available signal propagating medium without making it a y g p p g g g
common one.4. Gradual waking up of a person without giving him the option to defer the
waking up time indefinitely.waking up time indefinitely.5. Signals sent to the brain without leaving the entire decision of waking up on
it.6 M k th b d h i ll ti ith t d di h i l6. Make the body physically active without depending upon physical
movements.7. Supplying energy to the system without reducing the source power level.8. Variable signal generation at the source without variation at the receiving
end.9 Signal transfer without propagation9. Signal transfer without propagation.10. Send multiple sensory input to the brain without increasing system
complexity. 53
Ideal design: Alarm clock
• Ideal design: waking up a person without using• Ideal design: waking up a person without using any external device.
• Alarm in the biological clock of a person.• Very bright sunlight that surrounds the sleeping person
t th ti f k ( t li bl t bli d l dat the time of wake-up (not applicable to blind people and for night time alarms).
• Use the carbon-dioxide exhaled by the person during the y p gsleeping hours to accumulate and wake him up by inducing discomfort.
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