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Detroit's New 'Car Guy'
Tom Watson, Design News' Engineer of the Year for 2006, is one of a new breed of automotive engineers who know energy management as well as they know engines and transmissions
Charles J. Murray -- Design News, March 19, 2006
The mechanical model atop Tom Watson's desk says it all. A 70-lb collection of cranks and gears, the model was built to show how power moves through Ford Motor Co.'s new hybrid vehicles. In truth, though, it's far more than a technology demonstrator. It's really a mock-up of Ford's future. Turn one crank and you simulate the action of a gasoline-powered engine. Turn another, and you spin a virtual traction motor. And the model's planetary gear set? Like Watson himself, it's responsible for parceling out the power, creating an almost-symphonic blend of torque and fuel efficiency.
And therein lies the essence of Tom Watson, Design News Engineer of the Year for 2006. Like the model atop his desk, Watson is responsible for blending two very different forms of power, and for leading the 103-year-old automaker into the new world of sustainable energy.
"This is our future," Watson says, referring to the mix of electric- and gasoline-powered propulsion systems. "Our strategy going forward is sustainability."
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Indeed, no less than William Clay Ford has deemed it that way. The giant automaker's high-profile chairman announced in September that Ford will aim to build up to 250,000 gas-electric hybrids by 2010 — a tenfold increase from its current production levels. That's why Watson — with his knowledge of engines, transmissions, energy management and powertrain control strategies — has suddenly become such an important cog. While much of America, from the press to the environmental lobby, was wringing its hands over the idea that U.S. automakers couldn't build a hybrid, Watson was adding experts to his team and refining Ford's hybrid technology.
And the results have surprised many of the naysayers. By most measures, Ford's Escape shot past comparable sport utility vehicles in the hybrid world's most important benchmark: fuel economy. The four-wheel-drive version, with its EPA fuel economy ratings of 33 mpg in the city and 29 mpg on the highway, bested both the Lexus RX 400h and the Toyota Highlander. Ford's performance was especially significant in the case of Toyota, the company with the most hybrid experience.
"It's pretty amazing that, even after everyone has written off the Big Three, we still have the highest fuel economy of any SUV in the marketplace," Watson notes. "At the same time, we're certified for better emissions status, as well."
Making Tradeoffs
That may have been why Design News readers chose Watson as their Engineer of the Year. The soft-spoken, 17-year Ford veteran has been a leader, initially in Ford's study of energy management, and later in the rollout of its first hybrid vehicle. In retrospect, Ford colleagues say Watson was an ideal man for the job, especially given the fact that the company's venture into the hybrid world was one that took it outside the prescribed boundaries of vehicle design and beyond the accepted dogma of everything its engineers learned during its century-long history.
"Tom went through a process of really learning the tradeoffs, of optimizing the use of the engine and traction motor and batteries," says Nancy Gioia, Ford's director of sustainable mobility technologies and hybrid vehicle programs. "It required an in-depth understanding of transmissions, engines and control strategies."
Doing all that wasn't easy, however, especially in light of Toyota's five-year head start.
"We'd never done a hybrid before," Watson says. "At the beginning of the design, we had to go all the way back to the point where the driver gets in the vehicle and turns the ignition key. And then we had to throw away all our intuition about the way vehicles are supposed to operate."
In many respects, Ford's task was not much different than it had been a hundred years earlier, when the company first settled on the idea of propelling its vehicles with an internal combustion engine. The task brought its engineers across the blurry line that separates engineering and science.
It was a task, however, that was well-suited to Tom Watson's experience. Watson, who holds a B.S. in mechanical engineering from the University of Illinois, began laying the foundation for his energy management knowledge while still an undergraduate student. Studying under Professor Robert White at the University of Illinois in the early 1980s, Watson learned about calculating road loads on vehicles by accelerating them to 80 mph, shifting their transmissions into neutral, and then studying velocity-versus-time graphs during "coast-down." Using calculus, he says, he learned to separate out the forces on the vehicles as a function of time, and then determine the effect and the source of those forces.
"One of the final things I did in school was re-derive all of (Professor White's) equations from scratch," Watson recalls. "In a sense, I was reverse engineering his equations."
When he joined Chrysler as an engineer in 1984, Watson picked up where he'd left off at Illinois, using coast-down testing to develop performance and fuel economy numbers. In 1989, he switched companies, joining an Energy Analysis Group at Ford, again to do fuel economy studies. In the early 1990s, he brought nearly a decade's worth of those studies to bear on the U.S. Senate in Washington, where, working as a lobbyist for Ford, he showed legislators the tradeoffs between manufacturer costs and fuel efficiency. Throughout this time, Watson also developed an intimate familiarity with virtually all of the components in a vehicle — engines, transmissions, brakes, tires, bearings, shafts, controllers, and even software — and their effect on fuel economy. Moreover, everything he studied was viewed through the larger lens of energy analysis, whether the energy source was gasoline, batteries or even fuel cells. Watson even developed statistical process control methods for use in Ford's CAE tools, to help the company's engineers more precisely predict the fuel economy effects of even the tiniest design changes.
"We wanted to be able to tell program teams exactly what their fuel economy was going to be, instead of having everyone get 'beat up' because they were one-tenth of a mile-per-gallon off on their numbers," Watson says.
In essence, Watson's first 15 years of automotive experience served as a primer for what was to come. By the time William Clay Ford began to charm the company's board of directors, the press, and the environmental lobby with his vision of a "greener" Ford, the wheels were set in motion toward a hybrid future.
"My director came to me and said, 'OK, Tom, you wrote a hybrid into the company strategy,'" Watson recalls. " 'Now, how'd you like to deliver the very first one?'"
Blending Engineering and Science
As soon as Ford launched its hybrid project in 1998, Watson began putting together the unusual team that served as the technical brains behind the Escape. The key, he says, was the mix of talent.
"This is the most intelligent team I've ever worked with," he notes. "We brought Ph.D.'s from research together with engineers who had decades of experience implementing (vehicle) programs. It was really an exciting combination."
Even today, Watson says, he continues to follow the same model, drawing together a 50/50 mix of engineers and scientists.
Eight years ago, however, nothing like that had ever been done on a Ford vehicle project. Watson served as the point man on the team, drawing on his background in fuel economy and computer-aided engineering analysis, as well as his knowledge of hardware.
"There was a small core of people within Ford who deeply understood hybrid technology," says David Cue, chief hybrid engineer for Ford. "Tom was one of those people."
Throughout the design of Escape's hybrid powertrain, Ford's team made extensive use of computer modeling to determine how each hardware and software change would affect the vehicle's fuel efficiency. Employing The Mathwork's Simulink software, team members developed a computer model for simulating fuel economy, and then tied that model directly to the control strategy in the powertrain modules.
"Every time we made a software change, we'd model it before testing it on the vehicle," Watson explains.
That strategy was critical for development because hybrids use multiple powertrain controllers. Ford employs nine such modules on its Escape, compared to the single powertrain module used on its conventional American cars and trucks. Modeling the control configuration in this way, the team was able to implement countless changes before installing them on prototype vehicles and testing them in thermal chambers, or on location in the field.
Ultimately, Escape's engineering team released more than a thousand software changes — approximately three a day over three years — on the Escape. Watson credits fellow engineers Joe Supina and Carolyn Prodin for juggling the changes, while handling the maddeningly complex task of determining fuel economy numbers. Doing so was critical, Watson says, because it enabled Ford engineers to fully understand the fuel efficiency effect of each of those changes.
"That's very powerful," Watson says now. "We needed to be able to understand every change: Was it taking us toward better fuel economy? Or was it moving us farther away?"
Redefining The 'Car Guy'
Ultimately, engineers integrated those software control strategies together with a planetary gear set, electric traction motor, generator motor, and an in-line four-cylinder engine, thus providing the power to drive the Escape. To get the best possible fuel efficiency, the system alters its use of the engine, generator, and traction motor for the particular situation. Below 25 mph, for example, it keeps the engine turned off and uses only battery power. On the highway, it employs a complicated "negative split" mode (see sidebar p.84). Similar to the system used by Toyota, it's known as a "Powersplit hybrid" and is said to operate like a continuously variable transmission.
Ford engineers say that the complicated nature of the hybrid powertrain is what sets the engineering task apart from the industry's first hundred years of automotive engineering. Hybrid engineers, they say, spend countless hours graphing the driving process to determine which power source works best under which conditions.
Moreover, the hybrid engineering process calls for a different skill set. No longer is it sufficient to be an old-fashioned "car guy" (a Detroit term used to describe automotive executives who grow up tinkering with engines). Now, the scope has broadened. Hybrid engineers must be able to step back and discuss energy management and CAE models. What's more, the big picture view — even for those schooled as mechanical engineers — must incorporate electronics and control strategies.
"The difference between conventional powertrain controls and hybrid controls is like night and day," notes Tom Gee, manager of controls and strategy implementation for Ford's hybrid programs. "In conventional vehicles, you deal with a single module that has control over the entire powertrain. In a hybrid, you've got distributed controls, integration issues, latencies and fault management. It's far more complex."
As a result, they say, the image of the "car guy" has evolved.
"Today's 'car guys' are 'computer guys,'" notes Gioia of Ford. "You've still got to have that love of playing with the engine. But you also need to be computer savvy in multiple ways."
Watson is such an engineer, which is why Ford's initial foray into hybrids has achieved such success. According to tests published by the Consumers Union, the Escape not only had better fuel economy numbers — its numbers were also more accurate than those of its competitors. By most measures, its EPA fuel economy figures (36 mpg in the city and 31 mpg on the highway for the front-wheel drive version, 33 mpg and 29 mpg for the four-wheel drive model) beat those of its hybrid competitors, the Toyota Highlander and the Lexus RX 400h, as well as those of its main conventional powertrain competitor, the Honda CRV.
Colleagues say Watson's leadership was critical to achieving those fuel economy successes.
"For Tom, it's about calibration, strategy and powertrain controls, but it's also about understanding the hardware," Gioia explains. "He knows what you can get out of your engine, transmission and mechanical interfaces. It's about depth and breadth. In this business, there aren't many engineers like Tom."
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Detroit's New 'Car Guy'
Tom Watson, Design News' Engineer of the Year for 2006, is one of a new breed of automotive engineers who know energy management as well as they know engines and transmissions
