Title: Engineering 1000 Chapter 3: Problem Formulation
1Engineering 1000Chapter 3 Problem Formulation
2Outline
- Teams and personalities
- Mental models
- Herrmann Brain Dominance Model
- Whole Brain Model
- Knowledge Creation Model
- Metaphors for creative problem solving
- personalities
- Mental blocks to creative thinking
- lessons from exercises
- Heuristics for problem formulation
- statement re-statement
- present-state desired-state
- Kepner-Tregoe analysis
3Camels
Somewhere in the Middle East, a man owned 17
camels his entire wealth. He had three children
who helped him in his transportation business.
While on one of their trips, the father fell ill
at an oasis. He called his children to his side
and told them his last will the oldest child was
to have half of the camels, the middle child one
third of the camels, and the youngest child one
ninth of the camels (which represented a fair
share of the time each had helped the father in
his business). Then the man died. After the
burial, the children were faced with the problem
of how to divide the camels according to their
fathers wishes. The discussion soon centred,
rather heatedly on how to kill and cut up some of
the camels to come up with the specified
shares. At this moment an old man arrived at
camp, hungry and thirsty, and with a camel in the
same condition. The old man listened to the
argument for a while and then offered to solve
the dilemma by giving them his camel, if they
would provide shelter and food for him for the
night. The children agreed. During the night, the
oldest child decided he better leave with his
share of the camels before the old man or his
siblings had a change of heart. Later, the
middle child awoke, noticed nine camels gone, and
hastened to depart with six. In the morning, the
youngest child, noting that the others had helped
themselves to their inheritance, took the allowed
two camels, and bid farewell to the old man with
thanks. The old man then resumed his journey with
his well-fed and rested camel.
Creative Problem Solving and Engineering Design,
Lumsdaine et al., McGraw Hill 1999
- What is the real problem here?
- How do we identify and formulate problems?
4Problems, Teams, and Personalities
- Much of engineering (and other business) is now
performed in teams - so it is not surprising that a lot of research
has been performed into what makes teams
successful - including the development and management of the
team, the roles and skills of the members, the
personalities of the members, conflict resolution - Along with the team management is a personal
emphasis - how do I learn to be a better team member?
- and hence to do well at my job
- To do this, we need to understand basic aspects
of our personality - so simple and reliable have been developed to
indicate basic personality types - the most famous is the Meyers Briggs test
- e.g. http//www.humanmetrics.com/cgi-win/JTypes1.h
tm
5Advantages and Disadvantages of Teams
- Advantages
- wider knowledge and experience is available
- interaction of people leads to synergy
- better chance of finding optimal solution
- team members accept the solution and work better
to implement it - team members learn from each other
- encourages development of leadership skills
- Disadvantages
- more time and personnel needed to build team
- team process has low efficiency lots of ideas
but few practical ones - team conflict
- group think
6A Good Creative Team
- What makes a good creative team?
7Mental Models
- Mental models are tools for aiding problem
solving - and for understanding why individuals tackle
problems in different ways - We will look briefly at three concepts
- the Herrmann brain dominance model
- knowledge creation
- creative problem solving
8Herrmann Brain Dominance Model
- Loosely based on the anatomy of the brain, this
technique uses a questionnaire to determine a
persons relative strengths in four quadrants
http//www.hbdi.com/
9- The profile for engineers is typically
- very strong in quadrant A
- less strong in B and D
- weak in C
- None of the categories is bad
- the idea is to identify your natural strengths
and to concentrate on developing your less strong
areas - with the aim of being equally strong in all
areas, i.e. multi-dominant or whole brain - Engineers with strengths in each category are
important - e.g. for a bridge construction
A technical specs, financing, project logistics
B low-risk, efficient work flow, how to build it
C connecting people, effect on communities and environment, politics
D traffic projections, different possibilities, aesthetics
10Whole-Brain
Creative Problem Solving and Engineering Design
Lumsdaine et al. McGraw Hill 1999
11In Which Quadrant Are You?
- Based on the data from the previous page give
yourself a score out of 10 for each quadrant - note this is not how the real test is done!
- When in a team, do you find yourself behaving
according to your dominant quadrant? - do you see others displaying other quadrants?
- do you see their contributions as valuable to the
team?
12Knowledge Creation Model
- How can the whole-brain model be extended to give
an understanding of the innovation process? - in Creative Problem Solving and Engineering
Design Lumsdaine et al. combine the whole-brain
approach with lessons for innovation drawn from
Japanese companies - The idea is that knowledge is created as we move
from one quadrant of the Herrmann diagram to the
next - It is important here to identify two types of
knowledge - Explicit knowledge
- hard knowledge that can be expressed in
formulae, descriptions, instructions, diagrams - it can be transmitted readily by manuals,
documents etc. - Tacit knowledge
- know-how, experience, intuition, craft, skill
- tacit knowledge must be transmitted by
interaction and personal instruction
13- The combined knowledge creation diagram
identifies four stages - socialization shared vision, corporate culture
- externalization discussions and brainstorming
- combination analysis and evaluation of concepts
- internalization learning and integrating the new
knowledge
Creative Problem Solving and Engineering Design
Lumsdaine et al. McGraw Hill 1999
14- You can see similarities/connections with
- the design process itself
- the levels of failure from Ch.2
15Example Oakland Bay Bridge
Early History Soc. Public discussion and increasing traffic needs after WW1.
Extern. 38 proposals and design concepts by 1928.
Comb. Board of 3 distinguished engineers recommends analysis of preferred site for more detailed design and cost estimates. benefits of bridge versus tunnel.
Intern. Focus on bridge failures with large cantilever designs.
Bridge Authority Soc. Political efforts underway
Extern. Creating a publicly-owned facility
Comb. Financing, appointment of state highway engineer, boring and analysis of potential sites
Intern. Detailed traffic studies, best route, California Toll Bridge Authority
Bridge Design Soc. Many engineers and consultants work together, port expansion wishes accommodated
Extern. Intensive design work on many designs, scenic beauty a factor
Comb. Engineering experience and judgement play key roles in narrowing down design possibilities. Switch from cantilever to suspension bridge on San Francisco section for economic, safety and aesthetic reasons.
Intern. Model testing carried out because multiple-span suspension bridge was a new concept
- Completed in 1936 ahead of schedule and within
budget
16http//www.lib.berkeley.edu/Exhibits/Bridge/bb_ce0
06.html
17Metaphors for Creative Problem Solving
- So far, we have considered the thought processes
and dynamics of knowledge creation - now we consider the mind-sets required at each
stage of the process - These mind-sets can be conveniently though of in
terms of fictitious personalities - these are the roles required during the different
phases of the knowledge creation process - Explorer
- is needed to seek out new ideas and to see the
opportunities presented by the big picture - Detective
- performs a more detailed analysis of the
situation - problem formulation typically ends after these
two roles - Artist
- generates creative and imaginative ideas
- but may not analyse them critically
18- Engineer
- shapes the creative ideas into something more
practical, examine the technical issues,
optimisation - Judge
- identifies flaws in the solutions proposed and
works with the artist and engineer to
overcome them - Producer
- puts it all together to come out with a good
product, i.e. solves the problems of
implementation - may be the project sponsor higher up in the
organisation - Without any one of these personalities, a
critical element of the problem-solving team is
absent - These personalities fit with the Herrmann diagram
and the knowledge creation cycle as shown on the
next page
19Creative Problem Solving and Engineering Design
Lumsdaine et al. McGraw Hill 1999
20Mental Blocks to Creative Thinking
- There are three common barriers to creative
thinking - false assumptions
- habitual thinking
- attitude barriers
- From the following list, choose who you think is
the most creative group of people - NASA engineers, high school teachers, homemakers,
college students, first graders, journalists,
movie producers, abstract painters, auto mechanics
21- An intelligent mind is a good thinker ?
- Not necessarily untrained intelligent people may
be poor thinkers for a number of reasons - they can create a good justification for any
point of view and do not see the need to explore
alternatives - they confuse verbal fluency for good thinking
- their mental quickness leads them to jump to
conclusions - they think that quick thinking is good
understanding - they use intelligence to criticise rather than
construct - Other valuable attributes
- play
- humour
- what if ?
22Exercises
- 1a. Which of these figures is different from the
rest? Why? - Reason
- 1b. An army must move some soldiers to a
different location. If a maximum of 39 soldiers
and their gear fit into a bus, how many buses are
needed to move 1261 soldiers? - (a) 31 (b) 32 (c) 32.33 (d) 33 (e) 34
- Answer
- 2. How many squares are there?
23- 3a. Join all the dots with 4 straight lines with
no more than one line through any dot - 3b. Sketch a path from A to B
24- 4. What do you see below?
25- 5a. What do you see?
- 5b. Can you find all 9 people?
http//www.grand-illusions.com/
26Bad Habits
- Exercise 1a 1b
- it is possible to make a good case for any shape
being the odd one out - hence the question is too vague
- Block 1there is more than one correct answer
- Corollary to exercise 1
- in order to know the best answer of those we
have, we must look at the context - Block 2 do not look at the problem in isolation
- Exercise 2
- the simple answer is that there are 17 squares
- but this is limited thinking, e.g. it assumes
that the picture is 2-D what happens if this is
looking at the top of a column of blocks? - Exercises 3a 3b
- thinking outside the box
- Block 3 following the rules
27- Exercise 4 to check progress
- chances are you answered a black dot
- possibly a rectangle containing a black dot
- in fact 95 of the rectangle is white space!
- Exercise 5a 5b
- shows ambiguous images can you see both images
interchangeably? - Block 4 discomfort with ambiguity
- very little in life is 100 clear including
ENG1000 assignments - Attitudinal blocks
- Block 5 risk avoidance/fear of failure
- if you never fail, youre not reaching far
enough - Block 6 negative thinking
- itll never work
28Problem Formulation
- Following our knowledge creation cycle, the
explorer and then the detective personalities
are appropriate for problem formulation - Problem formulation (or problem definition) is
needed to - ensure everyone realises that there is a problem
- and to specify the real problem
- On the following page, we see how the two
personalities approach the same issues
29Creative Problem Solving and Engineering Design
Lumsdaine et al. McGraw Hill 1999
30The Explorer
- The explorer personality is used for divergent
thinking - quadrant D thinking
- taking the far view
- spotting trends
- predicting the future
- How you become a trend spotter?
- be selective about information you take in
- read articles that contain ideas
- talk to people
- have broad-ranging interests
- synthesise ideas (i.e. think!)
- observe what is around you
- ask questions
- identify how things change over time
- find opportunities
http//www.angelfire.com/me/jakub/indy/
31The Detective
- In contrast to the explorer, the detective
specialises in convergent thinking - quadrant B personality
- looks for root causes
- accumulates information, surveys, data
- who, what, when, where, why, how much?
- Kepner-Tregoe approach (see later)
- explicit and tacit knowledge
- persistent
http//www.sherlock-holmes.org.uk
32Heuristics
- A heuristic technique is essentially a trial and
error approach - a number of options are generated and the best is
selected - a try-it-and-see experimental approach
- a rule of thumb
- We will look at several heuristic approaches to
problem definition - statement re-statement
- source and cause
- revision method
- present state and desired state
- Kepner-Tregoe situation analysis
- Remember that these (and the methods we have
already discussed) are merely aids for thinking - not guaranteed to produce good results
33Statement Re-statement Technique
- This approach aims to promote a better
understanding of a problem by stating and
re-stating the problem in different ways - hence focusing in on the problem
- The statement re-statement technique consists of
four parts - for which we assume there is a problem statement
of some sort already in existence - 1. Determine the real problem
- this can be done by rewriting the problem
statement to see what solutions are triggered - see next page
- 2. Determine actual constraints and boundaries
- sometimes the perceived constraints are tougher
than the real ones - in the problem statement, relax the constraints
to see if it has changed in a significant way if
not the original constraints were too tough - e.g. car gt500km/h replaced by car gt 200km/h
- e.g. lowest price replaced by affordable
34Restatement Description Increase the number of commuters who use the TTC
Vary the emphasis Has the focus of the problem itself changed? How? Is it a better statement? Increase decrease fares? Make more convenient Commuters advertise benefits of TTC to commuters TTC bus lanes, subway to York
Substitute explicit definitions Is the problem statement clearer and more precise? In what way? Why? Commuter ? people travelling to work each day encourage employers to reward TTC users. TTC ? trains/buses make working easier on trains/buses
Change positives to negatives and vice versa Reverse the statement. Instead of how to make the car faster, ask what slows the car down. Reduce the number of commuterswhy dont more people use TTC? Fix reasons.
Replace persuasive and/or implied words Where obviously or clearly occur, examine the reasoning. If reasoning is flawed, what effect will this have? Underlying reasoning is that by increasing TTC ridership, we reduce number of private cars, pollution etc. i.e. number of commuters is constant. Promote telecommuting instead.
35- 3. Prioritise goals
- as we saw in Ch.2, not all objectives are equally
important - satisficing
- 4. Link outputs to inputs
- determine what transforms inputs (raw materials,
people, money) into outputs (the desired benefits
of the design) - are any stages of the transformation process
missing? - are any stages unpredictable? What would you do
about them? - re-state problem statement to reflect what is
known, unknown, desired, and unpredictable
36Present State and Desired State
- An alternative heuristic approach to problem
definition is to focus on the present and desired
states - by manipulating statements of the present state
(PS) and the desired state (DS) we aim to make a
clear correlation between the two
PS too many commuters use private cars DS less
traffic PS too many commuters use private cars
because there is no viable alternative DS less
traffic PS too many people use private cars
because they must commute and they dont take
public transport DS we need to reduce commuting
by private car PS too many people use private
cars because they must commute and they dont
take public transport DS people should be
encouraged to reduce their commute or take public
transport PS too many people use private cars
because they must commute and they dont take
public transport DS people allowed to work
closer to/at home or public transport should be
made attractive
37- How would this sequence have been different if
the DS had been reduced pollution? - The PS/DS approach can be expressed
diagrammatically - in the so-called Duncker diagram
Engineering by Design G. Voland, Addison
Wesley, 1999
38- This is very similar to the objectives and
functions trees we saw in Ch.2 - except that the aim is to start from the PS and
DS and work from both ends - it enables both more complex and multiple
statements to be included simultaneously
39KepnerTregoe Analysis
- In their 1981 book The New Rational Manager
Kepner and Tregoe developed a four-step problem
solving approach - Situation Analysis (SA) critical aspects first
- Problem Analysis (PA) what past event may have
caused problem? - Decision Analysis (DA) what actions are needed
to correct problem? - Potential Problem Analysis (PPA) how to prevent
further problems? - SA and PA are relevant here
- DA and PPA are used later in the design process
- Kepner-Tregoe is now a large management
consulting and strategy company - http//www.kepner-tregoe.com
- This analysis is primarily intended for
engineering problems in progress - but can aid in structuring the search for the
real problem in any design process
40Situation Analysis (SA)
- The current situation is analysed according to
three criteria - timing which is the most urgent problem?
- trend is the problem getting better or worse?
how quickly? - impact what are the consequences of the problem
being left unsolved? - For each problem and sub-problem, each criterion
is given a high, medium, or low ranking of
importance - see example from p.90 of Engineering by Design
(reproduced here for convenience)
41Example The Water Tank Disaster
- The following news story is based on the Nassau
edition of Newsday, the Long Island, N.Y.,
newspaper (April 24, 1981 ) and OPLOW, American
Water Works Association, vol.7, no.6,June 1981,
p.3. - Inadequate safety precautions and an accident
inside an empty water tank caused the deaths of
two workmen in New Jersey on April 23. At 4 P.M.,
a scaffold inside the tank collapsed and caused
the two men painting the tank to fall to the
bottom. Stranded there, they were overcome by
paint fumes and eventually lost consciousness.
John Bakalopoulos, 34, of Brooklyn, N.Y., and
Leslie Salomon, 31, also of Brooklyn, were not
wearing oxygen masks. The Suffolk County Water
Authority's contract for the painting job
specified that workmen wear "air hoods," masks
connected to air compressors. The masks were
available, but Bakalopoulos and Salomon had
decided not to wear them because they were
unwieldy. Instead, Bakalopoulos wore a thin gauze
mask designed 4to filter out dust and paint
particles. Salomon wore no mask. - Peter Koustas, the safety man who was handling
the compressor and paint feed outside the tank,
asked a nearby resident to call firemen sic as
soon as he realized the scaffold had collapsed.
Then he rushed into the tank with no oxygen mask,
and he, too, was overcome by the fumes and lost
consciousness. The men lay unconscious for hours
as rescue efforts of more than 100 policemen,
firemen, and volunteers were hampered by bad
weather. Intense fog, rain, and high winds made
climbing the tank difficult and restricted the
use of machinery. Several men collapsed from
fatigue.
42- Inside the tank, conditions were worse. Because
of the heavy fumes, rescuers used only hand-held,
battery-powered lights, fearing that sparks from
electric lights might cause an explosion. Lt.
Larry Viverito, 38, a Centereach, N.Y,. volunteer
fireman, was overcome by fumes 65 ft (20 m) above
the floor of the tank. Fellow rescuers had to
pull him out. - Rescuer John Flynn, a veteran mountain climber,
said he hoped he would never have to go through
anything like that night again. For five hours he
set up block-and-tackle pulleys, tied knots,
adjusted straps on stretchers, and attached
safety lines and double safety lines. The
interior of the tank was as blindingly white as
an Alpine blizzardcompletely and nauseatingly
disorienting. Fans that had been set up to pull
fresh air into the tank caused deafening noise. - When Flynn first reached the tank floor, he
stepped into the wet paint and began to slide
toward the uncovered 4-ft (1.2 m) opening to the
feeder pipe in the center of the floor. Flynn was
able to stop sliding, but John Bakalopoulos
wasn't as fortunate. - As rescuers watched helplessly, Bakalopoulos,
still out of reach, stirred, rolled over, and in
the slippery paint slid into the feeder pipe. He
plunged 1 10 ft (34 m) to the bottom. - Bakalopoulos was dead on arrival at the
University Hospital in Stony Brook, N.Y., Peter
Koustas, rescued at 145 A.M. and suffering from
hypothermia, died the following morning when his
heart failed and he could not be revived. Only
Leslie Salomon survived.
43- Although there may be additional concerns that
could be identified (such as rescue expenses and
the subsequent use of the water tank), let us
assume that Table 3.2 includes the major elements
of the problem. A review of the priorities given
to each subconcern indicates that "paint fumes"
received high levels of concern in all three
categories (timing, trend, and impact) for both
paint crew members and their rescuers. Therefore,
we should initially focus on this most urgent
aspect of the situation. - This first step in Kepner-Tregoe analysis further
requires that we classify each aspect of a
situation into one of three categories,
corresponding to the next step (problem analysis,
decision analysis, or potential problem analysis)
to be performed in resolving the problem. In the
case of the water tank problem, since we already
know the cause of the paint fumes (the paint
itself), Kepner-Tregoe problem analysis is
unnecessary we would move directly to decision
analysis (see Chapter 10 of text) and strive to
eliminate the need for painting the tank.
From Engineering by Design G. Voland, Addison
Wesley, 1999
44Problem Analysis (PA)
- SA aids our determination of which problem(s) to
tackle first - problem analysis assist our thinking for a
specific sub-problem - PA asks the following questions
- what is the problem? and what is not?
- when did the problem occur and when did it not?
- where did the problem occur? and where did it
not? - what is the extent of the problem?
- much of this seems like common sense, but it
helps to have a structure to follow in instances
of duress like drilling soldiers - These key considerations are summarized as
- identity, location, timing, magnitude
- The aim is to determine why there is a difference
between is and is not, between positive and
megative
45Engineering by Design G. Voland, Addison
Wesley, 1999
46Example - Electronics Manufacture
An electronics manufacturing company is involved
in the demanding task of producing miniaturized
printed circuitry. One day, the production
quality fell off sharply and the number of
rejected circuits skyrocketed. "Why?" demanded
the boss. "Why?" echoed his subordinates.
"Temperature in the leaching bath is too high,"
said one technician. So temperatures were
lowered. A week later, when rejects climbed
still higher, temperatures were raised, then
lowered again, then systematically varied up and
down for days. Rejects remained astronomical.
"Cleanliness is not what it should be. That's
what's causing the trouble," someone offered. So
everything was scrubbed, polished, filtered, and
wiped. The rejects dropped, then rose again. Acid
concentration was the next idea. Same results.
Water purity was checked out on Wednesday,
Thursday, and Friday. The possibility of oil
transferred from the operator's fingertips
received full scrutiny on the following Monday
and Tuesday. Rejects still were high. They might
have remained high had not one supervisor begun
to ask systematic questions. "What is wrong with
the rejected pieces?" This produced the
information that the acid leaching step of the
printed circuit pattern was occurring unevenly as
if some waterborne contaminant in the leaching
solution was inhibiting the action. "When does
it occur?" A check of the records showed that
rejects were at their highest on Monday mornings,
lower on Monday afternoons, and gone by noon on
Tuesday.
47- This cast a different light on everything. Now
nobody was asking "Why?" about the cause of a
general, ill-defined deviation. Instead they
focused on what was distinctive about Monday
mornings compared with the rest of the week. They
focused on what might have been changed that bore
a relationship to this timing. An immediate
distinction was recognized "Monday morning is
the first work period following the non-work
period of the weekend." And what changed on
Monday morning? On each Monday, as soon as the
tap was turned, water that had stood in the lines
over the weekend came into the printed circuit
leaching laboratories. - The water used in the process had to go through
intensive purification, since purity standards of
a few parts per-billion are required. A quick
search turned up the fact that some valves had
been changed several months before. These valves
used a silicone packing material. As water stood
in the lines over the weekend, enough of this
silicone packing material had begun to diffuse
into the water and degrade the leaching process.
The result? Many rejections on Monday morning,
fewer in the afternoon, and none after Tuesday
noon. By then the contaminated water had been
purged from the system. - From The New Rational manager, C. Kepner and B.
Tregoe, Princeton Research Press, 1981.
48Summary
- A good problem definition is necessary for a good
design or solution - Understanding of thinking preferences and
elimination of poor thinking techniques assists
the process - Using metaphors can help to adopt the necessary
approaches to the problem - Certain techniques (heuristics) can assist in the
process of formulating the problem
49Homework
- Read and understand Chapter 3 of the text book
- Read the case studies
- Do problem 3.7
50Exercise Leaking Oil
- Apply Kepner-Tregoe analysis (SA and PA) to
determine the priorities and possible causes of
the following problem
- Our client is a major food processor. One of the
company plants produces oil from corn and
soybeans. The five units that filter the oil are
located in one building. On the day the problem
was first observed, a foreman rushed into his
supervisor's office "Number One Filter is
leaking. There's oil all over the floor of the
filter house." - The foreman guessed that the leak was caused by
valves loosening up from vibration. This had
happened once before. "Number One sits right next
to the main feedwater pump and gets shaken up
more than the other four filters." A mechanic
tried to find the leak but couldn't tell much
because the oil had already been cleaned up. The
lid fastener looked all right. After examining
pipes, valves, and the walls of the filter
chamber, the mechanic concluded that the oil had
spilled from another source. - The next day there was more oil. Another
mechanic traced the leak to the cleanout hatch
but that didn't help much. Why should the
cleanout hatch leak? It looked perfectly all
right. Just to be on the safe side, he replaced
the gasket even though it looked new. The hatch
continued to leak. "Maintenance people just
aren't closing it tight enough after they clean
it out," someone volunteered. "There are a couple
of new guys on maintenance here since the shifts
were changed around last month. I wonder if
they're using a torque wrench like they're
supposed to. This happened to us once before
because somebody didn't use a torque wrench." No
one could say for sure.
51The next day an operator slipped on the oil-slick
floor and hurt his back. The cleanup task was
becoming more than irksome, according to some
outspoken comments overheard by the foreman. A
few people began grumbling about promises made at
the last safety meeting about improving
conditions in the filter house. Two days later
the plant manager got wind of the situation,
called in the supervisor and the foreman, and
made it clear that he expected a solution to the
oil mess problem within the day. From The New
Rational manager, C. Kepner and B. Tregoe,
Princeton Research Press, 1981.