What is the real problem?
A student and his professor are backpacking in
Alaska when a grizzly bear starts to chase them
from a distance. They both start running, but
it’s clear that eventually the bear will catch up
with them. The student takes off his backpack,
gets his running shoes out, and starts putting
them on. His professor says, “You can’t outrun
the bear, even in running shoes!” The student
replies, “I don’t need to outrun the bear; I only
need to outrun you!”
Problem Formulation
This is the most important step in the
process. For proper formulation:
Focus on function
Example: “enhance communication
between all parties” versus “design a
better telephone system”.
Problem Formulation
•
Avoid giving specific solution. This
would limit the search for solutions.
•
Define the “real problem” not the
“perceived problem”.
Example
-Needs assessment :
Low speed collisions result in too much damage.
-Problem Formulation:
Design a front bumper that can withstand low
speed collision.
Specifications
Additional requirements and limitations may
modify the statement to read:
Design an inexpensive front bumper
so the car can withstand a 5 mph head-on
collision with a fixed concrete wall without
significantly damaging the bumper or other
parts of the car. In addition, the bumper must
be easily recyclable.
Constraints
Constraints: In order to prevent overriding bumpers in collision between
automobiles, the federal government
requires that all bumpers be installed 18”
up the ground. The weight of the bumper
cannot exceed 50 Ib.
The basic types of problems
1. Prediction :
calculating a result or predict a system’s
behavior by applying equations, physical
laws, tools analysis, etc.
2. Explanation:
searching for the cause of failure.
Continued …
3. Invention:
developing a new and effective solution to a
problem.
4. A combination :
One make seek to prevent satellites
from falling (a problem of invention), but
he must first determine the cause for such
flight failures (a problem of explanation).
Search for the Problem

When the phenomenon is not known, we need to
search for the problem.

Example: what caused the crash of the DC-10
(AA Flight # 191)?
Structuring the Search for the Problem
Formulation

Objective (Why?)
Focus upon function.

Background (Who? Where?)
Who will be served by a solution with the
environment in which design is expected to
be used?
Structuring the Search for the
Problem Formulation …

Methodology (How? When?)
Description of the approach that will be
used to develop the solution.

Expected results (What?)

Costs
Techniques for Problem
Formulation
The Statement-Restatement
Determine the real problem (in contrast to the
stated problem) by varying the emphasis on
certain words and phrases in the problem
statement. Ask yourself if the focus of the
problem itself changed. In what ways?
Example: Coating for tablets (pills).
The Statement-Restatement …
Determine the actual constraints or boundaries (in
contrast to the given or inferred boundaries). One
relaxed constraint may have altered the entire
focus.
Example: using “less than 200 lbs” in place of
“less than 100 lbs”
The Statement-Restatement …
Identify meaningful goals (in contrast to a set
of given goals). Ask yourself if all the stated
goals are equally important?
Try to prioritize the goals and then focus upon
the most critical ones as you rewrite the
problem statement.
Example: Increase the number of
commuters who use public transportation.
The Statement-Restatement …
Identify relationship between inputs, outputs, and
any unknowns. What are the inputs (materials,
people, equipment, money)?
What additional data to be collected? The
problem statement should then include what is
known, what is unknown, and what is sought in a
solution.
Other Strategies
One strategy for formulating a clear problem statement
is the so-called present state-desired state technique.
One begins by specifying (as best as one can) the
present or problem state (PS), and then the desired or
solution state (DS). One then modifies both the PS and
the DS until there is a satisfactory correlation between
the two.
The Dunker Diagram is often used as a graphical
approach to the PS/DS technique
4/13/2015
The Dunker Diagram is often
used as a graphical approach to
the PS/DS technique. The
Dunker Diagram presents three
classes of solutions.
1. General Solutions come in two forms:
• Those that require some action to be taken to
achieve the desired state.
• Those that transform the desired state until it
matches the present state.
2. Functional Solutions are derived from the
general solutions without regard to feasibility.
3. Specific Solutions are feasible solutions derived
from the functional solution list.
The Dunker Diagram can also be used without the
present state - desired state formulation
Problem
Positive
General Solution
Negative
General Solution
Functional Solutions
Functional Solutions
Specific Solutions
Specific Solutions
Dunker Diagram
Example of Dunker Diagram
Toasty O’s was one of the hottest selling cereals
when it first came on the market. After several
months the sales dropped. Surveys determined the
customer’s dissatisfaction: Cereal was stale when
purchased.
Needs Assessment: Cereal is stale.
Example Continued ….

Perceived problem: We do not get the product to
market fast enough.

Solution: Streamline the production process to get
the cereal on the store shelves faster thus ensuring
fresh product.
Dunker Diagram
Cereal not getting to market fast enough to maintain freshness
Get cereal to
market faster
Make it OK for cereal
NOT to get to market faster
Functional Solutions
Functional Solutions
Specific Solutions
Specific Solutions
Homework:
Chapter 3
Structuring the search for the
problem.
Pages 87-114