1998 Discover Technology Awards: Transportation

Wednesday, July 01, 1998
The key to being a successful inventor, thought Jeffrey Bentley, is to invent something that people will want to buy. As obvious as this old saw sounds, Bentley struggled for years to reconcile it with his growing conviction that fuel cells would someday replace the internal combustion engine in automobiles. Fuel cells work by combining hydrogen and oxygen to create electricity, without the noise and pollution of conventional engines. Since engineers have not found a safe and acceptable way to store hydrogen fuel in cars, Bentley made a prototype fuel cell that could operate on methanol or ethanol, using a chemical process known as partial oxidation to break these hydrocarbons down into hydrogen plus carbon dioxide. Then he realized his folly. His local service station was offering neither methanol nor ethanol at its pumps. So who would buy a fuel-cell car?

"I came to the conclusion," says Bentley, "that you've got to adapt to the current infrastructure."

Bentley went back to the drawing board. The big problem with gasoline is that it contains sulfur, which would destroy a fuel cell. Bentley added a catalyst to remove the sulfur and demonstrated his prototype last October. "The environmentalists didn't like it," he remembers--they didn't want to encourage burning more fossil fuels. But his gasoline-powered fuel-cell system should double mileage and cut down on emissions as well. And, Bentley notes, the system can burn ethanol and methanol as well as gasoline, so it offers an intermediate step between gas-powered cars and those running on renewable fuels.

Bentley, who is now chief operating officer of Epyx Corporation, a spin-off company formed to commercialize the hydrogen-producing system, said fuel cells must get a lot cheaper if they are to have a chance of pushing the internal combustion engine off the road.




FINALISTS

Underwater Airplane
Hawkes Ocean Technologies' Deep Flight
Innovator: Graham Hawkes

Graham Hawkes always regretted that he wasn't born 75 years earlier. If he had been, he might have been the one who built and flew the first successful airplane. Now, however, he's done what he thinks is the next best thing. He's invented a piloted underwater vehicle that is so fast and so maneuverable that it makes its predecessors look as unwieldy as hot-air balloons.

That's how Hawkes disparagingly describes the submersible craft he's made for the past 20 years for scientific research, work on offshore oil rigs, and the search for undersea treasure. They are slow, with a practical top speed of about one and a half knots, and cumbersome. "Deep Flight was born out of frustration," he says. "I wanted to build submersibles that would go faster and farther down than customers were interested in." So for eight years, with the help of volunteers, Hawkes built a new type of undersea craft--a one-man torpedo with wings that zips along at seven knots and turns with the touch of a button.

Last summer he took Deep Flight for a test run in the Pacific. "It was magical. I was engaged in this beautiful ballet with giant manta rays swimming just a few feet away." Lying flat with his head in the transparent nose cone, he felt as if he were gliding and not in a craft at all.

Hawkes designed Deep Flight to dive to 3,000 feet. As it is, the device would be useful to marine biologists, except that Hawkes isn't interested in making any more of them. Rather, he already has plans for Deep Flight II, built of composites and able to withstand the huge pressures at the deepest part of the ocean--the bottom of the Mariana Trench, 36,000 feet down. Deep Flight II would make a round-trip in only a couple of hours, leaving plenty of time for exploration. The major hurdle is money--it could cost $5 million to build two Deep Flight II submersibles that can be joined together to allow for a pilot and a passenger.




Quick! Hit the Brakes!
Mercedes-Benz's Brake Assist
Innovator: Manfred Steiner

When stopping a car in an emergency, 20 feet can make the difference between a fender bender and a fatality. Manfred Steiner, an engineering project manager with Mercedes-Benz, says his Brake Assist will provide those 20 feet.

In the late 1980s, Mercedes-Benz researchers discovered that most drivers do poorly in emergency braking. They press down quickly on the brake pedal--some three times faster than in normal braking--but without enough force. "In the first second there is only a reflex reaction," Steiner explains. After that, the driver sees how the car is slowing and pushes harder, but by then it may be too late. So Mercedes-Benz decided to create a system that would detect emergency braking and apply maximum force to the brakes faster than a driver can.

Steiner directed a team of engineers to add electronics to the braking system that can sense when the driver depresses the brake quickly.

Steiner's team then modified the booster mechanism that multiplies the force of the driver's foot on the brake. The booster has two chambers, both vacuums and separated by a movable partition attached to the brake. When the driver pushes on the brake pedal, a valve opens in one chamber and lets air flow in, forcing the partition toward the other chamber and applying extra pressure on the brake. Normally the booster adds braking power proportional to the push on the brake pedal, but when a driver hits the brake with extra urgency, Steiner's added electronics opens the valve on the brake booster as far as it can go, applying maximum power on the brake.

Mercedes is installing the Brake Assist in all its 1999 cars. The company says it will cut as much as 45 percent off the stopping distance for average drivers. Even if a driver is slow to jam on the brakes, it can slice 20 feet off an emergency stop--more than a full car length, and enough to save a life.




Bird Power
MIT's Proteus, the Penguin Boat
Innovator: Michael Triantafyllou

It started when Michael Triantafyllou, an ocean engineering professor at mit, was on sabbatical in Greece, looking into alternative technologies for propelling boats. This work led to Robotuna, a four-foot-long mechanical fish, whose tunalike undulations proved more efficient than propellers at turning mechanical energy into forward motion. But unless Triantafyllou could figure out how to get a boat to wiggle like a fish, there was no way to apply lessons learned from Robotuna to ship design. So he had graduate student James Czarnowski find another sea animal that might offer more practical inspiration. Czarnowski found them waddling around the zoo: penguins. "When they're swimming, their bodies are rigid, like little torpedoes," he says. "Their sole means of propulsion is their flippers." (For flippers, read wings.)

After watching penguins swim around in the New England Aquarium in Boston, Czarnowski mapped out the movements of their flippers. He designed his propulsion system, which has two vertical paddles, blunt at the end with tapered, trailing edges, to mimic those motions. A collection of motors and gears drives each paddle side to side while simultaneously rotating it first in one direction, then in the other. (Hold your palms in front of you; move them toward each other while turning your palms slightly downward; then move them away with the palms slightly upward.)

In the spring last year Czarnowski mounted his penguin flippers on the back of a 12-foot test hull and launched the boat, which he named Proteus for the sea god in Greek mythology, on the Charles River near mit. It moved along quite efficiently. According to lab tests, the penguin boat transforms 87 percent of the energy input into forward motion, compared with 50 to 70 percent for propeller-driven ships. "The penguin boat demonstrates for the first time that this unsteady propulsion--unlike the continuous propulsion of propellers--is highly efficient and improves the ease with which boats can be maneuvered," says Triantafyllou. Even with that much improvement, the shift from propellers to flippers would be so radical that Czarnowski guesses the penguin boat will probably first appear in niche markets, such as in Florida, where manatees are often injured by the propellers of passing boats. This could be avoided if boats had flippers instead.




Don't Check the Oilr
Puradyn Filter Technologies' Filter Plus
Innovator: Byron Lefebvre

Trucks go for more than a million miles without an oil change, thanks to an oil-filtering system invented ten years ago at tf Purifiner in Boynton Beach, Florida. The filter keeps engine oil as clean as a fresh can of oil by removing solid contaminants as small as 1 micron (about two ten-thousandths of an inch)--compared with about 15 microns for standard oil filters--and purging liquid impurities, which conventional filters don't handle at all. The filter saves thousands of dollars and reduces waste oil. Ironically, the 1992 Clean Air Act, which forced diesel engine manufacturers to decrease the pollution emitted by their engines, also ensured that these filters would no longer work.

"All that stuff has to go somewhere," says Byron Lefebvre, a technical director at Puradyn Filter Technologies, as Purifiner is now called, "and it's going to end up in the oil." The filter, of course, will clean the oil, but it takes time to do so, and in the meantime the filter relies on additives in the oil to neutralize the contaminants. But the added contaminants deplete the oil of its additives too quickly--before the truck makes it to its next maintenance check, when it gets topped up with fresh, additive-rich oil.

One solution was to replenish the additives by pouring them in manually every few thousand miles, but that "can really upset the balance of the additives," says Lefebvre. In February 1997 he added a component to the filtering system that slowly releases additives into the oil. The filter holds the additives in the form of pellets, which slowly dissolve as the oil passes over them. Now trucks using the filter change it every 20,000 miles or so, add oil as needed, and otherwise leave the oil alone.

The filters are not likely to make it into cars largely because automakers don't believe customers will pay extra for them--though Lefebvre has no idea what they might cost. When he bought a car, he put a Puradyn system in it. Nine years and 145,000 miles later, he hadn't changed the oil, and the car ran just fine. Then he sold it, oil and all.
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