Engineering 1000 Chapter 7: Synthesis. Synthesis 2 R. Hornsey Outline Introduction to synthesis...
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Transcript of Engineering 1000 Chapter 7: Synthesis. Synthesis 2 R. Hornsey Outline Introduction to synthesis...
R. HornseySynthesis 2
Outline Introduction to synthesis Design space
what is it? complex and large design spaces expanding and limiting the design space
Design by accident Synectics
making the familiar stange making the strange familiar
Analogies direct, fantasy, personal, symbolic, biological
Morphological charts Prototypes and proof of concept Exercise
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Introduction to Synthesis Synthesis: the putting together of parts or elements so as to
make up a complex whole (Oxford English Dictionary) So far we have been systematically building up towards a
design solution we worked out what the design should do we clarified our objectives and added constraints we refined the problem statement and structured the problem we generated new ideas and thought creatively we structured the search for solutions to sub-problems
Now we are seeking to combine the various elements into a selection of complete and potentially workable solutions
the selection between these potential solutions will occur in the analysis phase
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Design Space What is ‘design space’?
it is a mental framework encompassing all the potential solutions to a design problem
the concept of ‘space’ is useful because it conveys the idea of freedom to movement
Hence, a large design space has many potential solutions or many parameters, and may be difficult to navigate
e.g. a Boeing 747 has approximately 6 million parts A small design space is highly constrained, with minimal
‘freedom of movement’ e.g. the design of an image sensor pixel
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Complex Design Spaces A design space can be complex, even if is not large Complexity can result from the interdependency of even a few
parameters especially if some of the dependencies are very sensitive to each other or if precise conditions cannot be known hence the system is hard to optimise e.g. the image sensor pixel again
We have already covered how to deal with complex design spaces by decomposition
in other words, by subdividing the problem into manageable units We will see a new one here – the morphological chart – which
will help us to: decompose the overall problem into sub-problems identify a means to solve each sub-problem synthesise the parts back into a coherent whole
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Expanding the Design Space When we talked about creative thinking, we were effectively
developing techniques for expanding the design space Using existing information
benchmarking competitors’ products reverse engineering patents
Team activities brainstorming convergent and divergent thinking (explorer and detective) statement restatement Kepner-Tregoe
In the same way we had metaphors for thinking – explorer, engineer, artist judge etc – we can have metaphors for ways to expand the design space
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Design by Accident
The story of Teflon® began April 6, 1938, at DuPont's Jackson Laboratory in New Jersey. DuPont chemist, Dr. Roy J. Plunkett, was working with gases related to Freon® refrigerants, another DuPont product. Upon checking a frozen, compressed sample of tetrafluoroethylene, he and his associates discovered that the sample had polymerized spontaneously into a white, waxy solid to form polytetrafluoroethylene (PTFE).
PTFE is inert to virtually all chemicals and is considered the most slippery material in existence. These properties have made it one of the most valuable and versatile technologies ever invented, contributing to significant advancements in areas such as aerospace, communications, electronics, industrial processes and architecture. As DuPont registered trademark Teflon®, it has become a familiar household name, recognized worldwide for the superior non-stick properties associated with its use as a coating on cookware and as a soil and stain repellant for fabrics and textile products.
The Teflon® trademark was coined by DuPont and registered in 1945; the first products were sold commercially under the trademark beginning in 1946. Applications and product innovations snowballed quickly.
http://www.dupont.com/teflon/newsroom/history.html
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Synectics “A method of problem-solving, esp. by groups, which seeks to
illuminate and utilize the factors involved in creative thinking” (OED)
it is designed as an aid to overcoming the barriers to creativity we explored in Chapter 3
The principal exponent of synectics is W.J.J. Gordon see “Synectics: the Development if Creative Capacity”, W.J.J. Gordon,
Harper & Row 1961 (YUL BF 408 G64) Synectic theory is based on three assumptions
creative efficiency in people can be markedly increased if they understand the psychological process by which they operate
in creative processes, the emotional component is more important than the intellectual, the irrational more important than the rational
it is these emotional, irrational elements which can and must be understood in order to increase the probability of success in a problem-solving situation
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Synectics aims to promote creative thinking by two principal techniques
making the strange familiar making the familiar strange
The root of this idea is the recognition that creative thinking is impaired in two potential ways
the problem is so far beyond our everyday experience that we cannot imagine how it could be solved
or that the situation is so familiar that we cannot conceive of a better way of solving the problem, e.g. a paperclip
[see Petroski’s books for discussions on the ‘perfection’ of paperclips] To download a ‘lite’ version of the software Axon ‘idea
processor’, which incorporates elements of synectic thought: http://web.singnet.com.sg/~axon2000/index.htm
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Making the Strange Familiar The mind tends to analyse a new situation by forcing the
problem to fit existing preconceptions the strangeness is compared with data previously known to eliminate
as much of the strangeness as possible this is the whole point of the paradigm and the paradigm shift it is a reflection of the fact that human thought tends to be conservative
In engineering terms, one obstacle in this process is the quantity of analysis required for the translation
Equally, translating everything to the mundane also risks losing the innovation inherent in the strange idea
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Making the Familiar Strange “Genius . . . means little more than the faculty of perceiving in
an unhabitual way” William James, The Principles of Psychology
This action is very tough to perform because strangeness and uncertainty are uncomfortable
To overcome this, synectics makes extensive use of analogies personal analogy direct analogy symbolic analogy fantasy analogy
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Post-It Notes Making the familiar – adhesive – strange by Art Fry from 3MMy work has always been in new product development. Post-it note had its start in 3M's Central Research Department when Dr. Spence Silver was looking for ways to improve the acrylate adhesives we use in many of our tapes and in the medical, industrial and office markets. He was really trying to make them stronger by experimenting with new materials in the molecule and by changing the way they were made. What followed was a classic case of serendipity, where you find something you are not looking for.
He had discovered an adhesive that formed itself into tiny spheres the diameter of a paper fiber. The spheres would not dissolve, could not be melted, were very sticky individually. When they were coated onto tape backing, they would not stick very strongly, because the little spheres made intermittent contact between the tape backing and whatever you tried to stick them to, as compared to normal adhesives with smooth surfaces that make complete contact. He tried it again, and got the same result. It is always exciting for scientists to be able to duplicate their work.
Spence had discovered a new adhesive, but had no good idea of how to use it. If he had thrown it away, we all would have been the losers. Instead, he diligently told about his discovery to others in 3M that used adhesives. I went to one of his seminars and scratched my head, thinking that it was interesting, but I, too did not know how to use this new adhesive.
This was a long introduction to your question about how I felt when I invented the notes and how I feel in retirement. I can remember the aggravation when it was time to stand up and sing in my church choir, only to find that the little piece of paper that I used to mark the music had fallen out, making me fumble about, trying to find the right page. This was followed by a dull sermon and my mind was wandering back to the music problem when I had one of those "flashes of insight": Eureka! I think I could make a bookmark, using Dr. Silver's adhesive, that would stick and remove without damaging the book.
R. HornseySynthesis 13
The next day at work, I gathered paper and adhesive and prepared samples of the bookmark. I gave samples to my secretary, my supervisor, and to other colleagues. They were pleased to get them, but after two weeks when I asked them if they wanted more, they said the bookmarks were working well, but they had not used all of the samples I had given them.
A short time later, I was writing a report and had a question about a piece of information, so I attached a sample of my bookmark to the report with an arrow pointing to the information and my question on the note. Bob Molenda, my manager at the time, wrote his answer on the bottom of the note and attached it to an item he was returning to me. It was during a coffee break the afternoon when we both realized that what we had was not just a bookmark, but a new way to communicate or organize information.
Self-attaching Notes!
Wow! we were very excited. My colleagues started using their bookmark samples as notes and soon were at my desk saying that they were instant addicts and demanding more samples. As the circle of addiction quickly spread within our product development laboratory, I came to the very exciting and satisfying realization that those little, self-attaching notes were a very useful product.
This of course, was just the beginning of the innovation process. Samples had to be tested for every conceived and inconceivable application that we could think of. Many people thought they were frivolous or too expensive as compared to scratch-paper, but management still gave our small team the chance to continue. Our team soon was enlarged by others who recognized the merit of the notes and we set off on the tough task of building a business structure.
I remember the reaction of engineering and production people who said, "What you are asking us to do is very difficult! None of our coating processes is suitable for your product. We do not have a good means of measuring the minute amounts of adhesive you need, and we can find no one that knows how to put sticky sheets of paper into the precise pads that you ask for!" I said, "Really. That is great news! If it were easy, then anyone could do it. If it really is as tough as you say, then we are the ones who can do it." People like a challenge that measures them. They like to contribute their time to something that they feel will succeed. We had many tough problems to solve in manufacturing, quality, packaging, and sales. It took a lot of us to solve those problems, and we all feel good about what we did.
quoted from http://mustang.coled.umn.edu/inventing/Postit.html
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Analogies
In the early 1940's, Swiss inventor George de Mestral went on a walk with his dog... Upon his return home, he noticed that his dog's coat and his pants were covered with cockleburrs. His inventor's curiosity led him to study the burrs under a their natural hook-like shape.
This was to become the basis for a unique, two-sided fastener - one side with stiff "hooks" like the burrs and the other side with the soft "loops" like the fabric of his pants.
The result was VELCRO® brand hook and loop fasteners, named for the French words "velour" and "crochet.” www.velcro.com
R. HornseySynthesis 15
Direct Analogy Analogy:
inference that if two or more things agree with one another in some respects they will probably agree in others
resemblance in some particulars between things otherwise unlike The direct analogy makes links between the present problem
and similar problems that have already been solved Sun Tzu’s “The Art of War” is used for business strategy Lego is analogous to real building bricks “rip-stop” fabrics are derived from parachutes to miniaturise an MP3 player, see how digital cameras are miniaturised if you want to make a lightweight, strong laptop, look to see how other
light and strong objects are made (e.g. planes)
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Fantasy Analogy ‘Fantasy” in this case is interpreted as ‘beyond belief’ Many of today’s commonplace technologies were imagined by
earlier science fiction/fantasy writers escalator moving staircases (Arthur C. Clarke) the laws of robotics (Isaac Asimov) submarines (Jules Verne)
Fantasy analogies can be used to remove a block in the design process
“imagine the solution to this exists, and let’s carry on” Or can be used to approach a practical solution from the
reverse
“When I examine myself and my methods of thought, I come to the conclusion that the gift of fantasy has meant more to me than any talent for abstract, positive thinking.” Albert Einstein
solution fantasy analogydirect analogy
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Symbolic Analogy The symbolic analogy sums up the objective in a way that is
not technically accurate but captures the essence of the situation
we want a car that moves like ‘greased lightning’ a seal that is tighter than a ‘clam shell’ a solution that is ‘outside the box’ a basketball shoe that sticks to the floor ‘like glue’
Many of these subconscious similes can suggest ways in which the problem can actually be solved
This can also involve ‘pictorial’ thinking e.g. imagining electrons in an atom to orbit the nucleus like planets
around a sun electrons in a semiconductor to act like balls (see below)
R. HornseySynthesis 18
Personal Analogy In the personal analogy, the designer imagines being part of
the system when I teach how transistors work, I encourage students to “think like
an electron” electrons move in response to voltage gradients like a ball does to
physical hills and valleys (a symbolic analogy!) so you can imagine how you would respond to the electrical
environment as if you were the electron I used to think that this pictorial thinking was rather simplistic until I
discovered that the famous physicist Richard Ferynman did the same thing for quantum mechanics
This requires a certain empathy with the problem at hand i.e expertise and familiarity with the situation
R. HornseySynthesis 19
Bionics – Biological Analogies
In many situations, particularly in mechanical and civil engineering, nature has solved the problem already
Velcro being a good example animal backbones are similar to bridges bamboo is similar to (and in some
countries used for) scaffolding tubes are used for mechanical stiffness in
many applications e.g. truck crank shaft, spider legs, many plants, pipes, bones
artificial neural networks are based on models of the brain
radar and sonar are similar to the echo location of bats, whales and other sea mammals
www.batworld.org
R. HornseySynthesis 20
Many medicines are derived from naturally occurring substances
a famous example is aspirin
The effects of aspirin-like substances have been known since the ancient Romans recorded the use of the willow bark as a fever fighter. The leaves and bark of the willow tree contain a substance called salicin, a naturally occurring compound similar to acetylsalicylic acid, the chemical name for aspirin.
In 1897, a German chemist with Friedrich Bayer and Company was searching for a treatment for his father's arthritic pain and began to research acetylsalicylic acid, which worked well. As a result, he developed a product introduced as Aspirin. By 1899, The Bayer Company was providing aspirin to physicians to give to their patients.
www.bayeraspirin.com
R. HornseySynthesis 21
Checklisting Asking the appropriate questions can often hasten the
determination of a solution Checklisting is one approach to this which combines elements
of Kepner-Tregoe and statement re-statement what is wrong with it? what doesn’t it do? what is similar to it? why is it necessary? what can be eliminated? how can its assembly be improved? what new materials could be used? in what way is it costly? are there any other applications? in what way is it inefficient? can it be improved ergonomically?
R. HornseySynthesis 22
Limiting the Design Space All the previous examples were intended to expand the design
space but instead we sometimes need to limit the design space so we can
reach a manageable solution Here we can use some of the tools already introduced for
structuring the search for a solution general constraints (safety etc) objectives and specific constraints (design goals) order and structure our objectives (trees and Kepner-Tregoe) eliminate impossible solutions
R. HornseySynthesis 23
Morphological Charts Morph charts are a widely used technique for getting an idea
of the size of the design space and for synthesising partial solutions to the problem
morphology is the study of structure or form (Webster) again, the start of the process is similar to the objectives tree, except
we are primarily interested in features and functions rather than objectives
The morph chart is a means to select ideas that really work The list of functions and/or features should be at the same
level of detail in the objectives tree and now we include all the possible ways of achieving these
functions/features we will return to our beverage container example from Chapter 2 …
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Beverage Container Objectives Tree Features and functions of the
container might include contain beverage material for container access to juice display product information sequence manufacture of juice
and container These are identified with the
general objective to “promote sales”
How might we implement each item on the list?
C.L. Dym & P. Little, "Engineering Design: A Project-Based Approach", Wiley, 2000
R. HornseySynthesis 25
Contain beverage can, bottle, bag, box
Material for container aluminum, plastic, glass, waxed cardboard, lined cardboard, mylar film
Provide access to juice pull-tab, inserted straw, pop-up straw, twist-top, tear corner, unfold container, zipper
Display product information shape of container, labels, colour of material
Sequence of manufacture serial, concurrent
Implementation
R. HornseySynthesis 26
Beverage Container Morph Chart The morph chart shows this information in a visually useful
way
All we need to do is choose one option (1,2,3 …) for each feature, as above
1 2 3 4 5 6
Contain beverage can bottle bag box
Material for container
aluminum plastic glasswaxed card
lined card
mylar
Provide access to juice
pull tabinserted
strawtwist top
tear corner
unfold zipper
Display product information
shape labels colour
Sequence of manufacture
concurrent serial
means
feature/function
R. HornseySynthesis 27
Design Space and Morph Charts How many potential design options are there?
4 x 6 x 6 x 3 x 2 =864! Of course, not all of these 864 solutions are feasible
e.g. glass can with a tear-off corner Hence the morph chart can be used to highlight impossible
solutions and hence to limit the design space constraints etc. can also be employed in the same way also incompatible pairs can be eliminated (e.g. card and zipper) this is effectively the activity of synthesis
Note that the functions and features were all identified with a fairly high (less detailed) level in the objectives tree
means of achieving shock and temperature resistance would be included on a separate morph chart because they were considered to be at much more detailed
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Example:AnalogComputer
C.L. Dym & P. Little, "Engineering Design: A Project-Based Approach", Wiley, 2000
R. HornseySynthesis 29
Prototypes The next stage of the design process might be to build a
prototype of the outcome of the morph chart or to perform modelling or simulation of several of the options
A prototype is a working example of the finished design, or part of a design
it should resemble the final design as far as possible in its functioning although the method of manufacture may be different (e.g. individually
crafted rather than moulded or stamped – hand produced instead of mass-produced)
Extensive testing of the prototype identifies behaviours that were not anticipated in the original design and provides an opportunity to fix them
prototypes may also be used to obtain data for improved modellingm theory and simulation
Pre-production models (equivalents of beta versions of software) may also be tested on eventual users of the product
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Proof of Concept Proofs of concept are similar to prototypes but are usually
closer to the ‘R’ end of R&D They are typically versions of a final object that are restricted
in some way they are used to prove that an idea works and is worth exploring further the idea should, in principle at least, be expandable or scaleable to the
final object For example
Marconi’s first transatlantic radio transmission Bell’s first telephone call Bardeen, Brattain, and Shockley’s first transistor
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Summary In this chapter, we have explored the concept of design space
and how synthesis fits within the design process We looked again at how the design space could be expanded
to increase the number of new design options synectics is one technique for expanding the design space we also considered analogies as a means to understand and solve
problems Morphological charts provide a good way to reorganise design
possibilities to help identify new combinations and to eliminate impossible
combinations Prototypes and proofs of concept are often essential ways of
demonstrating and evaluating new designs
R. HornseySynthesis 32
Homework Read Chapter 7 of textbook
there are some sections we didn’t cover here Read case studies 7.1 to 7.9 – they’re interesting! Do problems 7.1 to 7.10