Chapter 1: Introduction
Product Design and Development
Fourth Edition
by Karl T. Ulrich and Steven D. Eppinger
Why are we here?
• How does this course help me be a better
engineer?
• How does this course fit into the curriculum?
We want you to be able to solve problems
To solve problems, you need
• Skills
• Knowledge
Some problems are technical and some
are not.
Let’s Look at Two Problems
• Suzlon Wind Turbine Blades
• Toyota Accelerator Issues.
Suzlon Wind Turbine
• In 2008, Suzlon held more than 50 percent of
the Indian market for wind and 12.3 percent
of the global market.
http://www.topnews.in/companies/suzlon-energy
Problem
• On October 24, 2008 a Suzlon wind turbine in
Wyanet Illinois and one of its 140 foot long
blades break off.
http://gigaom.com/cleantech/holy-breaking-wind-turbines/
• Root Cause Analysis and Identification
• Suzlon engaged Navigant Consulting, to conduct an
extensive Root Cause Analysis (RCA)
• While designed and tested to industry standard
certification guidelines, the blade had a weakness in
the transition area - about 6 meters (20 feet) from
the root of the blade. The blades measure 43 meters
(142 feet) long and weigh 7 tonnes (15,650 pounds).
• At the completion of the program, only 179 blades of
the total fleet of 1,251 blades developed cracks.
However, Suzlon upgraded the entire fleet in support
of its customers.
http://www.prnewswire.com/news-releases/suzlon-completes-blade-retrofitprogram-64007317.html
This looks like a technical
problem.
How do you (as a designer)
prevent this from happening?
Toyota Accelerator Problem
http://www.toyota.com/recall/videos/pedalassembly.html
Recalls
• Nov 02, 2009 – US: 3.8 million Toyota and Lexus vehicles again
recalled due to floor mat problem, this time for all driver's
side mats.[5]
• Nov 26, 2009 – US: floor mat recall amended to include brake
override[32] and increased to 4.2 million vehicles.[citation needed]
• Jan 21, 2010 – US: 2.3 million Toyota vehicles recalled due to
faulty accelerator pedals[6] (of those, 2.1 million already
involved in floor mat recall).[3]
• Jan 27, 2010 – US: 1.1 million Toyotas added to amended floor
mat recall.[33]
• Jan 29, 2010 – Europe, China: 1.8 million Toyotas added to
faulty accelerator pedal recall.[7]
Toyota Will Pay Additional $32.425 Million as Result of 2
DOT Investigations
Dec. 20: Toyota has agreed to pay an additional $32.425
million in civil penalties as the result of two separate
investigations into the automaker's handling of auto recalls.
Toyota will pay the maximum fines allowable under the law
- $16.375 million in one case and $16.050 million in the
other - in response to the Department's assertion that it
failed to comply with the requirements of the National
Traffic and Motor Vehicle Safety Act for reporting safety
defects to NHTSA.
http://www.nhtsa.gov/Vehicle+Safety/Additional+Information+on+Toyota+Re
calls+and+Investigations
Wheels:
NASA: "Toyota problem not rocket science"
by John Shook, Lean Enterprise Institute
http://www.designfax.net/enews/20110301/
feature-4.asp
NHTSA-NASA Study of Unintended
Acceleration in Toyota Vehicles
http://www.nhtsa.gov/UA
What was the Toyota Problem?
• Mostly NOT technical. (Electronics cleared by
NASA)
• It was a perception problem.
• The problem resulted when the opposition
took control of the story.
• How do engineers deal with nontechnical
problems?
http://www.designnews.com/article/455235Friction_Fundamentals_and_Accelerating_Cars.php
The accelerator pedal assemblies in the vehicles
(Tundras) contained a friction lever made of the
polyamide (nylon) 4/6 material.
Toyota's investigation found that the material was
susceptible to humidity, which could cause the friction
lever to absorb moisture and swell.
It is well known that nylon is a hygroscopic (waterabsorbing) polymer.
http://www.designnews.com/article/448825Poor_Plastic_Selection_Caused_Gas_Pedal_Failures.php?nid=2334&rid=2501252
How do we design to avoid technical
and nontechnical problems?
• How do we select design goals and constraints
for an accelerator pedal assembly? (e.g. Grab
three other engineers and go to a conference
room for an hour.)
• How do we explore possible solutions?
• How do we select a “best” solution?
Course has Three Significant
Components
• Design Process and Methodology.
• Using Statistics to developing and apply Math
Models for design (DOE and Robust Design).
• Economic Decision Making
Goals of Book and Course
• Examine structured approaches to product
design and development (e.g. functional
decomposition, set-based design, …)
• Develop the knowledge and tools to be able to
work successfully on cross functional teams
(e.g. identify customer needs, intellectual
property, economic decision making, …)
Bias of the Book
• Assumes a For-Profit enterprise
• Considers primarily Discrete Goods (printers,
and power drills rather than plastic film)
• Considers primarily Physical Products rather
than engineering services or software.
Bias of the Teacher
SMIU Rules for Good Design
• Does not hurt anyone
• Makes money
• Works OK
Excellent Design
• Enhances lives
• Makes tons of money
• Delights the user
Role of Structured Methods
• Creativity vs. Recipe in design
• Creativity vs. Recipe in product development
process
Pretty Good Pictures of the Disassembled gas pedal
assembly:
http://www.thetruthaboutcars.com/exclusive-ttac-takesapart-both-toyota-gas-pedals/
Reasonable overview of the Problem with pretty good pictures.
http://www.thetruthaboutcars.com/why-toyota-must-replace-flawed-cts-gas-pedal-with-superiordenso-pedal/
Interface of
interest.
Comment on Design News Article about the Toyota
Accelerator Issue:
I don't believe that Engineering at Toyota was not aware
of a problem or concerns in a Safety Critical system like
a drive by wire accelerator.
Proper Failure Mode Analysis was not done or the risk
evaluated too small.
http://www.designnews.com/article/talkback/448825Poor_Plastic_Selection_Caused_Gas_Pedal_Failures.php#142509