for the ASME Design Conference, Boston, Wednesday, September 20, 1995

by John H. Lienhard
Mechanical Engineering Department
University of Houston
Houston, TX 77204-4792

It's a great pleasure to be here. In one sense, I'm an outsider looking in on design. But in another, since I'm an engineer, design is at the center of my being. All my life I've designed. Early in my engineering life I taught design. I've designed highways, fittings for the B-52, attachments for tractors, and every kind of experimental apparatus.

You cannot be an engineer without designing. You cannot really be an engineer without ever experiencing the elemental joy of conceiving in the mind and executing in the world.

Now I get to address the impossible question: "What is the future of engineering design?" Well, that future cannot be predicted, it can only be created. We have to create it without knowing just what it is we're creating.

When I first spoke with Farrokh Mistree and Richard Berkof about a vision of the future of design, that was a primary sticking point.

The future is the product of non-linear processes. If you were capable of writing equations for the future, they would be non-linear. And non-linear time-dependent equations are hopelessly dependent on initial conditions.

We never shall be able to predict the future of anything. Take the future of weather. If a butterfly chances to flap its wings in Beijing in March, then by August hurricane patterns over the Atlantic will be completely altered.

Yet the future of design is your responsibility. How do you shape a future that's completely unknowable? You will shape it. That's for sure. But how?

For guidance I suggest you take a look at the July issue of Mechanical Engineering magazine. The Silicon Graphics Computer Company took out an eight-page advertisement.

It's all about New Zealand's recent victory in the Americas Cup races. New Zealand won 39 heats in that competition and lost only one -- that by a mere 15 seconds.

The U.S. had dominated the race for years. A decisive win by bucolic New Zealand was as unthinkable as David slaying Goliath. The gleeful Silicon Graphics ad tells about it.

New Zealand went to computer fluid-flow analysts at Carnegie-Mellon with a large grant. The experts spent five years setting up means for testing boats, not in the water, but in computer simulations.

Computer modeling of fluid flow is elusive and difficult. The Carnegie engineers used the latest research, but they still could only come close to real performance.

So they set up a team right at dockside in San Diego -- twenty feet from a workshop. Using Silicon Graphics computers, they created a ritual of rapid trial and error.

Analysts would do maybe 200 designs a night -- design a boat, sail it in their electronic ocean, make another change, sail it again. Next day, the shop people would change one of two real boats and run it against the previous boat in the real ocean.

What once took years now got done in hours. The team tested 10,000 such designs, gaining a few seconds at a time on the course.

A 1990 article on yacht design in the Annual Review of Fluid Mechanics tells about another humiliation for the U.S. team -- the 1983 victory of the Australian entry. Same story: The Australians leap-frogged us with a radical new hull design based on sophisticated computer-aided design methods.

Now: What were the ingredients of this design success? Three things came together: rapid trial and error, powerful cooperation, and a new way of seeing. To create effective design strategies for the 21st century, these are the elements we should look at.

First, trial and error. Do you know the story of Lulu-Belle? We found out about German combat jets in the middle of WW-II. That struck a bolt of fear in our hearts, make no mistake. We were lucky that threat wasn't unleashed until the very end.

The few Messerschmitt jets Germany managed to finish marched through our bomber formations like Sherman on his way to the sea. If they'd turned up earlier, they might've changed the outcome of the war.

The German jets had been on the drawing boards since the late 1930s. We didn't start building our own jets until 1943.

On May 17th of that year, a Lockheed engineer named Kelly Johnson showed a jet design to the Air Force. By 2:00 that afternoon, he was on the way back to California with a contract in his pocket.

The problem was, Lockheed was already building every airplane humanly possible. They had no extra means to put into Johnson's project. But poverty of means gave him a wealth of freedom and opportunity.

Johnson set up a circus tent. He stole engineers from other units. The operation took its name -- the Skunk Works -- from the comic strip Li'l Abner.

Only 128 people worked in the original Skunk Works, and only 23 of them were engineers. Johnson was an impossible boss -- so impossible that no one took his impossibility seriously. "He used to fire me twice a day," said a lead engineer.

The work was so secret that janitors weren't let in the tent. Trash piled up, and the work went on in cockamamie independence for 143 days. They named the new plane Lulu-Belle, and the Skunk Works took it from preliminary drawings to a finished airplane in less than five months. Today, it takes more like 8 years to do that.

Lulu-Belle was the experimental version of the F-80 Shooting Star -- our first jet fighter. Lulu-Belle flew 500 miles an hour in her test flight. Later she did over 600 miles an hour with a beefed-up engine.

This engineering tour de force came too late in the war to see combat. But in Korea, the F-80 jet that followed became the first jet to win a dog-fight with another jet.

The Skunk Works stayed intact at Lockheed after the war. It gave us our high-altitude spy plane, the U-2. A Skunk Works engineer explained these successes:

The trick, he said, is to design a plane as quickly as possible, and then cover your mistakes. The more time you spend getting a thing right the first time, the more chance people have to complicate it -- the harder it is to fix anything.

In the end, the Skunk Works had been forced into a perfect recipe for success. The usual organizational structure -- and the self-protection that goes with it -- had been shredded. Engineers were flung into the same rapid-fire trial-and-error mode that spelled success for the New Zealand boat.

Mark my words here. Organizations don't like the error part of trial-and-error, and that's extremely bad for effective design.

The halls of industry ring with slogans like, "Zero Defects" and "Do it Right the First Time!" Well, I tell you:

                  Know how to compromise with imperfection.  

        and       Do it wrong the first time.
After all, you can't learn from your mistakes if you don't have the courage to make mistakes. And the only things it's possible to do right the first time are things you've already done a hundred times.

The second idea that designers are coming to understand in new terms is cooperation. William Gordon drove that point home in his book Synectics 34 years ago. Gordon told designers they had to function both subjectively and cooperatively to produce good designs. He told us that we had to learn to "Make the Familiar Strange!" -- that we must see things through new eyes. To do that we first have to learn to work together and expose ourselves to one another as we work.

The most pernicious myth of design and invention is the myth of the lonely genius. Edison is the most famous case in point.

Edison was self-educated and isolated by partial deafness. The myth was made to his measure. And he fed the myth all his life.

Edison studied electricity on his own. He filed his first patent at 21. By the age of 29 he set up his own company. He located in Menlo Park, New Jersey, where he had some seclusion. But -- he was still only an hour's train ride from New York or Philadelphia.

For ten years, Menlo Park was Edison's season in the sun. He filed his 500th patent near the end of that time. It was a small operation. One building housed his office and a library. The labs and shops were in a two-story building.

So what did Edison really do there? He built a small coterie of bright engineers, scientists, and technicians. He created a complex, delicate, and unique collaboration.

Menlo Park gave us dynamos, improved telegraph and telephone systems, the precursor to the FAX machine, electric rail systems, and the photo-electric effect. It gave us the finished incandescent light and the phonograph.

Then, in 1884, Edison's wife died of scarlet fever. That, and I suppose success itself, spelled the end of the greatest gush of pure invention the world had ever seen.

In 1886 Edison remarried and moved into a much larger laboratory in West Orange, New Jersey. He continued inventing for another 45 years -- another 500 patents before he died.

He did a lot after Menlo Park, but it paled against that ten-year season in the sun. After Menlo Park, Edison lost his edge. What he really lost was the delicate chemistry he'd forged among that cadre of geniuses and craftsmen.

Edison was a genius, too. But the most important thing he'd really invented was a mode of working together -- an esprit de corps among a whole group of people. That spirit is what it took to make geniuses of the people he'd gathered around him. Those inventions weren't in a million years the work of a lonely genius.

So 21st-century design will be forged from a far better sense of the error part of trial and error. It will be forged from a rediscovery of cooperation. And finally I come to my title: to the matter of seeing. Let's talk about Gothic Cathedrals.

Suppose you were asked to design a quarter-mile-long structure, as tall as a typical downtown office building. Then suppose you were told it was to be made of stone -- no steel beams, no concrete -- and that the only available power had to be at ground level: horses, oxen, and maybe a three-horsepower water-driven saw.

Finally, the straw to break the camel's back: You have to do the job with no working drawings.

Sound impossible? Well, that's what the medieval cathedral builders did, over and over. We read a lot about cathedrals, but we seldom weigh them as engineering construction projects. In fact, they took remarkable coordination of people and materiel.

The master mason was in charge. He was architect and builder rolled into one. He often directed a work force numbering into the hundreds. But he also worked among his people. He cut stone and he raised scaffolding.

That part puzzles us, wed as we are to the notion that academic and manual knowledge don't mix. Yet it is here we see the almost mystic dimension of cooperation once more.

The subtle grace of the Gothic cathedral, which touches us so powerfully on so many levels, was a stunning feat of engineering design. Those barrel vaults, flying buttresses, Gothic arches, and spiral stone staircases were all born of concepts that were only fully expressed in the mason's mind before they were actually built.

Masons had no symbolic mathematics. Many couldn't even read and write. As we comb the rich medieval record, we don't even find architectural drawings. We find only the crudest sketches.

Yet medieval cathedrals are filled with geometry and proportion -- from labyrinths in mosaic floor tiles to the criss-crossing ribs that hold the ceiling.

What masons did have were dividers and a straight-edge. They had mathematics, but it was visual mathematics. I don't know if you've seen it done, but it's possible to do a perfectly rigorous proof of the Pythagorean theorem without words or symbols. All you need is a straight-edge and a carpenter's square.

So: the cathedral itself was the master mason's geometry. With his fingers touching stone, he used stone to express geometry. The balance of mass and space in a cathedral goes by square roots of 2 and 3 and the so-called Golden Section.

Medieval iconography regularly shows a pair of dividers in the hands of the mason. Medieval artists often showed God Himself as The Master Craftsman, holding a great pair of dividers.

So, if the mason had one overriding talent, it was an ability to visualize in three dimensions. Compare that with our work today. Our computers fairly sing with the ability to show us objects in 3-space.

They turn objects around and show them to us from every angle. They place you close up or far away. What the medieval engineer did in his head, the machine does for us.

But having done so, it then displays that object on a two- dimensional screen. What once went on inside our heads is now presented to our eyes. And that, I contend, is a terrible loss. Even fifty years ago, engineering students were still people who'd cut their teeth on sewing machines, model airplanes and Ford transmissions. Now they feast on Netscape.

I teach thermodynamics. Ask students to visualize p-v-T or T-s-p surfaces, and they look for them on their computers. They can no longer find those surfaces in their minds.

When I was a student, I entertained myself by inventing means for drafting a four-dimensional tesseract on a one-dimensional piece of string. Today, our bright students entertain themselves by programing graphical displays.

They can do what I could not have dreamt of doing. But the cathedral builders did what is unimaginable to us. And those skills were still present in the late 19th century.

J. Willard Gibbs erected the whole apparatus of thermodynamics in a stunning sequence of spatial constructs. The problem is, it wasn't until after WW-I that the academic world was able to figure out what he'd done. It all had to be interpreted back into graphs and mathematics.

When James Clerk Maxwell set the theoretical foundations of electric field theory in 1873, he said at the outset of his treatise,

Before I began the study of electricity I resolved to read no mathematics on the subject until I had first read [Faraday].
You see, Faraday's pioneering work made little sense to mathematicians. Now Maxwell, a great mathematician, systematically went back and climbed inside Faraday's head. There he found a great garden of delights. Here's what he said about the experience:
I found that ... Faraday's methods ... begin with the whole and arrive at the parts by analysis, while the ordinary mathematical methods were founded on the principle of beginning with the parts and building up the whole by synthesis.
Faraday was virtually uneducated, but he had an ace up his sleeve. He was dyslexic. And one typical dyslexic trait is a powerful visual sense. Faraday forged a finished image in his mind's eye, then he broke that image down into parts that people could understand.

Maxwell tells us that Faraday built a mental picture of lines of force, filling space, shaping themselves into lovely arrays.

Faraday drives his biographers crazy with the seeming irrationality of his thought processes. How can you start with the finished skyscraper, then build the foundation below it?

But Maxwell converted Faraday's vision of force fields into mathematical language and then plotted the equations. They form wild, graceful spider webs. And we see at last what Faraday had seen first.

But that leaves a nagging problem for us. Faraday's work came first. Maxwell cast that vision into mathematical terms, then laid it down on two-dimensional paper. The problem is, that's not how the vision came into being -- any more than Gibbs's thermodynamics came into being as thermodynamic graphs.

I am terribly afraid that the computer is so relaxing the eye or our mind that that eye will no longer serve us in the 21st century.

Indeed, notice that I've done something very unconventional here this morning. I'm talking to you without using the overhead projector. I do that because I so badly want you to follow me with the eye of your mind and not with the eyes in your forehead.

Now: Back to that dock in San Diego -- back to the design of the New Zealand boat. It embodied the three elements that must characterize engineering design in the 21st century.

                Trial and error


                            and  Spatial Visualization.
I've spoken about the first two. But the visualization part is more subtle. Since computational fluid dynamics is still a fairly crude art, the true design process went on in the workshop -- much as it did for a medieval mason. It was cut-and-try in the real world. The computer was only an extension of the mind. It was neither the beginning nor the end of thinking.

Now: what of the future? I would rank my hope for these three elements in the following order: I am most hopeful about the evolution of community. We're going to have a harder time accepting the importance of error in our work. As for visualization -- well, the deck is stacked against us there.

First, community: the computer networks are bringing a new creative anarchy upon us. The networks level hierarchy. They make a great Skunk Works of society. Industry is beginning to perceive that design will never flourish within a hierarchy.

The universities are also catching on. We're finally easing off on the requirement that students always work alone. We catch on to the fact that, like invention itself, learning is a communal act.

Design faculties have been leading the charge on that one. I have great hope that leaderless communities will emerge as the center of engineering design.

True trial and error is harder for us to accept. Industry doesn't want to lose time iterating. The people who look at profit and loss have a hard time understanding that the shortest distance between two points is almost never a straight line.

We faculty see ourselves losing the valuable class time that we need to "cover" everything. And we do lose time when we ask students to do open-ended exercises.

You and I know perfectly well that rapid trial and error -- a rapid learning curve, rich in possibility -- is the fastest road to good design. But it takes more courage than most of us have to go through the process. So we'll have to work very hard to hold on to that face of good design.

And as for visualization. There's where I have my greatest trepidation. Many people simply look at me as though I were crazy when I say that computer simulation is taking away our ability to visualize. The stuff on the screen is too lush. It's too compelling.

But visualization is where concept begins. The computer can't do that for us. Medieval masons literally built castles in the air, in their minds, before they built them on the ground. That's what we have to learn to do again. If we don't, the brilliance of computer displays will grow increasingly empty.

The drama I'm describing played itself out once before in human history. It went like this: The invention of printing, like the invention of the computer, began as an extension of old thinking.

The first printed books, beginning in 1455, were only facsimiles of the old hand-written manuscripts. It took about thirty years for printers to create a new vocabulary of illustration. In the mid-1480s we see the first scientific illustration in printed books. They were only crude sketches cut into woodblocks.

But, by 1525, the artist Albrecht Dürer had published the first textbook on descriptive geometry. He also honed the technology of copperplate engraving. Almost immediately, a new and accurate technology of printed illustration replaced the old mental constructs of the Medieval world.

Printing had, by then, reached the point that the computer has reached today. The result was the creation of an array of new sciences: anatomy, geography, botany, zoology -- all in forms that hadn't existed before.

For 265 years the new sciences limped along -- becoming more and more blatantly descriptive. Every now and then, a Galileo or Newton would plumb his own capacity for visualization and kick us forward.

But go back and read the old books. So many pictures and so little understanding.

Finally, around 1790, the Romantic poets began saying that -- and I quote William Blake here -- "Without man, nature is barren." They took 18th century science to task for all that undifferentiated observation. They told us that our minds must be part of the equation.

Scientists and engineers of the 19th century understood. And the scope of their work took a dazzling leap forward.

Now we face the same problem. The computer will create such a powerful illusion of visualization and creativity that we could well be in for another long dry patch.

So today I call upon you to capitalize on the powerful realization that we accomplish far more by building cooperation into our working methods. I call upon you to keep the error in trial-and-error.

But the most important thing I call upon you to do is to find a place for the eye of the mind -- the human mind -- in engineering design. For, believe me, it is under attack, and it is the most precious thing you all have in your tool kit.

Dietz, D., "Modeling Fluid-Structure Interactions," "Virtual Tests Help Kiwis Win America's Cup," Mechanical Engineering, Vol. 117, No. 7, July 1995, p. 18. (See also the Silicon Graphics Computer Systems advertisement on pp. 49-56.)

Larsson, L., "Scientific Methods in Yacht Design," Annual Review of Fluid Mechanics, Vol. 22. 1990, pp. 349-385.

Tierney, J., "[title unknown] ??," Science 85, September, 1985 ?, pp. 24-35. (The source for this is a Xerox copy of an article that was sent to me. I do not have a complete citation.)

Hughes, T.P., "Thomas Alva Edison and the Rise of Electricity," Technology in America: A History of Individuals and Ideas (C.W. Pursell, ed.), Cambridge, MA: MIT Press, 1986, Chapter 11.

Coldstream, N., Masons and Sculptors. Toronto: University of Toronto Press, 1991.

West, T.G., In the Mind's Eye: visual Thinkers, Gifted People With Learning Difficulties, Computer Images, and the Ironies of Creativity. Buffalo, NY: Prometheus Books, 1991.

Maxwell, J.C., A Treatise on Electricity and Magnetism. Oxford: Clarendon Press, 1873.