| by Jean
Thilmany, Associate Editor |
Wasn't
it Thomas Edison who made the quip about success? That it's 10
percent inspiration and 90 percent perspiration.
It makes you wonder what Edison might have explored if he had access to
analysis software. Computers don't do away with perspiration, but
virtual testing lets engineers extract more information today from much
less physical prototyping than they could in the past.
Modern analysis technology allows engineers to answer what-if questions
that would have been impractical, or perhaps impossible, to manage in
Edison's day, according to Stefan Thomke, an associate professor
of business administration at the Harvard Business School.
What if the earth quaked near a dam you designed? How would the dam be
affected? How could you design around that possibility?
You could model the soil in a computer and analyze its ability to remain
stable under a variety of conditions.
"Today's new technologies let experiments happen quickly
and easily," Thomke said. "Many new possibilities are created
through the what-if experimentation these technologies allow for. When
testing is very expensive, we don't try things out. These technologies
let us do that."
 |
| For large designs like a dam,
engineers rely mainly on analysis software. |
Thomke is the author of Experimentation Matters: Unlocking the Potential
of New Technologies for Innovation (Harvard Business School Press,
2003), which looks at how new technologies affect experimentation at businesses.
He says many businesses aren't properly set up to take full advantage
of new product development tools.
"Engineers can innovate, but as they come up with these new ideas,
they need them to be tested," he said. "They wait for feedback
from analysts, but there's a wall between analysts and engineers.
Analysts think of engineers as customers sometimes, and they have a long
queue of projects they need to look at. An engineer's project could
get put on a list, and he'd get a report back three months later."
That waiting game does not drive innovation. Because technology has moved
so quickly, companies have a hard time figuring out how to best incorporate
new analysis technologies into their established testing and analysis
structure.
Edison's was a classic way to innovate. He pushed his engineers
to experiment early, often, and always; he frequently claimed his measure
of success was the number of experiments that he could fit into 24 hours,
Thomke said.
But in Edison's day, experimentation took place quite differently.
In the inventor's laboratory, experimenter and machinist sat across
from each other. The engineer handed the machinist a part, who made it.
Then they tried it out. The engineer immediately redesigned the part based
on that trial, then handed the new design back to the machinist, who made
the new part. Then they tried it out again. You get the idea. That back-and-forth
continued until the experimenter was happy with the result.
Edison pushed engineers to test their designs as thoroughly as they could.
No one is about to suggest that physical prototyping and real-world testing
will ever become a thing of the past, but building prototypes has become
more expensive over the years as products have become more sophisticated.
Successful companies today allow for experimentation that strikes the
right balance between computerized simulations and Edison's hands-on
prototyping method.
A TEST RUN (LITERALLY)
Engineers at LifeFitness in Franklin Park, Ill., follow Edison's
testing dictum, although they've upgraded his design-test-redesign
method for modern times by merging simulated analysis with real-world
testing. Managers follow Thomke's advice by making sure they keep
the lines of communication between engineering and analysis departments
open and up to speed.
"We all work together from a design and analysis aspect,"
said John Rogus, a mechanical engineer at the company and part of the
newly formed mechanical engineering analysis group. His department works
closely with the design group to analyze parts as they're designed.
The company makes workout machines like treadmills and stair-steppers
for both cardiovascular and weight-bearing workouts at home or at the
gym. Of course, the company field-tests its equipment at the places where
it's used the most.
"We have arrangements with different clubs for field testing,"
Rogus said. "We do in-house testing where different people of different
weights, sizes, and conditioning use the machine, then we measure different
aspects of the machines with different people on them in different conditions."
But the company can't get by on field-testing alone. It also relies
on a full complement of analysis and reliability tests. For analysis,
the gym equipment maker uses Cosmos software from Structural Research
and Analysis Corp. of Los Angeles and a seat of analysis software from
Ansys of Canonsburg, Pa.
"We use analysis to determine and predict where the equipment is
going to fail and for comparative analysisto say this geometry
is better than that geometry in terms of stresses and things of that nature,"
Rogus said.
His company doesn't run FEA studies on every part. "That
would take forever," he said.
"But if a part fails during testing, we go back and look at it
with FEA to see why it failed and try to understand it better,"
he said.
Engineers and analysts work closely with the reliability engineers, who
are also in the loop. The latter group ensures that the machines are as
reliable as possible. They're the engineers who perform in-house
accelerated and component testing, working mainly with already-built machines.
TOO BIG TO BUILD TWICE
Sometimes a project is so big or so complex it can't be prototyped
for real-world study and Edison's back-and-forth method just won't
apply. When engineers at the FEA technology maker Abaqus of Pawtucket,
R.I., were asked to advise on how best to build an earthen dam, they couldn't
run out and construct a series of dams for study.
A South African company associated with Abaqus, Finite Element Analysis
Services, passed on information from a customer who had a question about
an earthen dam. Because Abaqus engineers knew certain problems applied
across the board to all dams made from earth, they decided to make a study
of the topic and prepare a paper from their findings, said Deepak Datye,
an Abaqus engineer.
An earthen dam is made by compacting layers of soil. Thus, designers have
to take into account two events that may cause their dams to fail: an
earthquake or a rapid emptying of the reservoir that the dam embanks.
 |
| With analysis technology, engineers
can ask many what-if questions. Engineers at LifeFitness of Franklin
Park, Ill., use simulated analysis and real-world testing to find
the most workable design. |
Engineers in Rhode Island couldn't travel to South Africa to study
the particular dam problem close up. And they certainly couldn't
build a large prototype dam for study and real-world analysis.
Nor in fact did they need to. They were analyzing problems designers might
face in constructing earthen dams in general. Local conditions were of
secondary importance. The Abaqus engineers relied mainly on their FEA
technology to describe how earthen dams are best designed to avoid the
earthquake or rapid emptying problems.
"We analyzed building a dam and filling it with water to find out
what the distribution of water pressure does to the dam," Datye
said.
Experimentation, analysis, and prototypingboth physical and virtualcan't
be sidestepped. But engineers need to strike the right balance between
physical and virtual experimentation appropriate to their companies. And
they need to ensure open lines of communication between analyst and designer.
"New technologies are revolutionizing how products are developed
today," Thomke said. "But, like anything new, they have
their challenges."
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