February 09, 2010
Toyota recalls: Deeper engineering implications
By Bill Schweber

We're all aware of the two mega-recalls of Toyota vehicles. The quick and easy explanation is that "cars are too complicated" and "cars have too many processors and too much software."

Certainly, there is some truth to that (software-controlled cars creep me out), but the sticking-accelerator problem has nothing to do with electronics; it's a mechanical problem with a mechanical solution. But the real problem which designers of mass-market, high-volume products really face is the law of large numbers. When you have tens or hundreds of thousands of a product out in the market, some of their incredibly obscure and subtle problems will eventually surface.

These secondary and tertiary effects are the manifestations of data points and sequences which are severe outliers, residing on the edges of that Gaussian curve. From an engineering standpoint, unfortunately, it's almost impossible to test for these circumstances.

Even if a designer diligently does life tests on a reasonable number of units, they will not uncover problems which occur only in extremely low numbers. It's one thing to stress-test a few hundred cars for tens of thousands of miles, but the truly rare problems which arise from hundreds of thousands of units are very different.

This testing dilemma became very clear to me when I met with the team at Tufts University which developed one of the wet labs on the Mars Phoenix Lander (See EE Times' story here:"Mars lander's chem lab is NASA's MECA"). The instrumentation package had a small drawer which had to open once--but only once--after the long and cold journey through space. I asked them what their biggest design challenge was, and they told me it was guaranteeing that the drawer mechanism would work. The problem was that it had to work once, and only once. Testing the mechanism over and over would not prove that it would work that critical first cycle, which is the only one that mattered.

The alternative test strategy would be to build hundreds, or even thousands, of these mechanisms and test them each once, which was obviously impractical. They did a lot of modeling, analysis, simulation, and tests, but in the end, could never prove with absolute certainty that the drawer would actually open that first time (which it did).

To those pundits in media who so quickly criticize the Toyota problem as a result of poor engineering and inadequate testing, I say "you have no idea what you are talking about." It's only because the basic design is so good and reliable, and the number of units on the road is so large, that these problems can even have a chance to appear. The law of large numbers is tough to work around, and does not yield easily to amendments.
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November 18, 2009
It's the battery, stupid
By Christoph Hammerschmidt

These days, first test results for electric cars driven under realistic conditions over relatively long periods have been published. With respect to driving range and energy costs, the results are a bad surprise across the board. Drivers report that under heavy load conditions, the driving range of e-cars melts away like ice in the sun. The nominal driving range is something no driver should rely on; instead, the real driving range is constantly far below the value indicated by the vendors. For instance, a test of BMW's e-Mini revealed real-world driving ranges of some 160 km — the nominal range propagated by the manufacturer is 250 km. On cold days when the test driver used the heater, the range dropped further — as expected — but the effective range of less than 100 km under these conditions is beyond any discussion.

But not only cold days take their toll. On hot summer days, it was the equipment such as pumps and fans necessary to keep electronics and batteries at their operational temperature that consumed extra power, again reducing the driving range.

And while in a normal car with combustion engine the tank can be filled in minutes, owners of e-cars have to be much more patient. The charging process takes as much time as a transatlantic flight, the tester of an Audi R8 e-tron noted. To charge a BMW e-Mini took some 12 hours when connected to a standard power outlet; when a three-phase power outlet was used, charging time was reduced to five hours — still much too long for everyday use.

To complete the negative picture, the energy costs for the electric sets of wheels appear not to be as low as e-car prophets have predicted. For the e-Mini, the electric power consumed burdened the driver's budget not less than a diesel car. While this calculation has been done on the basis of the high fuel prices in Germany, and in other countries the result may look somewhat friendlier, it shows that e-cars are not the economic sister of conventional cars (even if one does not take in account their high price).

So is e-car a dead-end street? Are critics such as Aston-Martin boss Ulrich Bez right who recently dismissed the e-car discussion as insubstantial hype? Wouldn't it make sense to focus R&D budgets on improving the efficiency of conventional drives? After all, there has been remarkable progress in the past years and engineers in tier ones promise to bring down fuel consumption by another 30 percent, so wouldn't it make sense to go this direction?

I don't think so. Indeed, it's the batteries that currently are the weakest part in the e-car concept. However, this is not a new insight; all battery manufacturers and e-car OEMs don't get tired of emphasizing this point. We should not forget that e-cars and the related technology are still in their infancy. It will take a decade or more to bring them to a performance level comparable to what we see in today's conventional cars. This takes a lot of stamina.

Hey, this is like the moon landing project: In the beginning, the goal was so high that many doubted it ever could be achieved. We now know that it paid out not to give up. The same wisdom holds true for alternative drive technologies and concepts — despite these disappointments.
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October 14, 2009
Car guys have blind spots
By Morry Marshall

Car guys, and I am one, have some blind spots. We want more car than we really need, or can use, and we think we're better drivers than we really are.

Those blind spots make us poor judges of what most people want or need, and of the cars that the automotive industry should be building in the future.

The car magazines lead us astray. Their road tests feature exotic cars: Ferraris, Lamborghinis, Lotuses. Those cars are desirable, but they are fantasies. Their production is only a tiny fraction of total worldwide automobile production. They are far beyond the means of all but a few readers. Their performance is beyond any reasonable requirement for driving on the road.

The implied standard of comparison in the car magazines is a racing car. Cars are often rated based on their performance on a race track. The assumption is that a car that performs well on a race track will be a desirable street car.

But performance on a race track has very little to do with desirable performance on the street. First, driving a high-performance car at anything near its potential on ordinary roads is unsafe, dangerous and potentially deadly. Second, a street car, even an exotic street car, is not a race car, no matter how well it performs.

Racing cars are stiffer, less compliant and lighter than street cars. They run on racing tires, and their suspensions are adjustable for maximum performance. Driving a racing car on the street would be a very unsatisfactory experience.

Many car guys believe that they are good drivers, maybe even as good as a racing driver. In truth, they are not even close to the capabilities of a competitive driver. If they ever had the opportunity to ride in a racing car on a road racing track with a top-level professional driver, as I have, they would learn that their driving skills are not even remotely comparable, even if they drove as fast as they would like to think they can.

Car guys need to overcome their blind spots and recognize some new realities. Oil supplies are dwindling and controlled by countries not particularly friendly to the U.S. Gasoline prices are eventually going to increase, probably to something beyond $10 per gallon. Most drivers don't share the enthusiasts' performance values or driving habits.

A new kind of automobile is going to be needed.

High performance cars are great fun and ego-gratifying, but the car of the future will not be a 600-horsepower monster that goes from 0 to 60 under five seconds. The future is more likely a plug-in, a hybrid, a diesel or a car with a smaller displacement gasoline engine. In whatever form, it should have fuel efficiency equivalent to gasoline engine mileage exceeding 50 mpg.

I'm not a tree-hugger. I'm not against high-performance cars or having fun while driving. But I believe it's time for enthusiasts to turn their attention away from ultimate performance and towards fuel efficient solutions.

You don't need horsepower to have fun. The 1945 MG TC had less than 55 horsepower. People thought it was a blast to drive, and it launched a sports car revolution. A 150-horsepower hybrid could start another auto revolution.

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August 26, 2009
The fastest little pushrod motorcycle in the world
By Morry Marshall

Pushrods may be passe' for Corvettes, as I recently suggested in an

A Chinese-made Dayun motorcycle recently set a speed record for its class--150-cc motorcycles with production pushrod engines--on the Bonneville Salt Flats. The two-way average speed was 61.77 mph. But wait a minute! Isn't that something like setting a speed record for the world's fastest rubber band-powered automobile? Where's the relevance?

The fastest speed attained by the Dayun motorcycle in tests, using a carburetor, was about 55 mph. The new speed record was established using fuel injection and ignition timing controlled by an electronic engine control unit (ECU) designed by ElectroJet, a Brighton, Mich., company and based on an MCU supplied by Freescale Semiconductor.

That's an improvement of more than 12 percent, a dramatic example of what can be done with electronic controls on a small gasoline engine.

Most people do not associate small gasoline engines with huge numbers or with air pollution, but hundreds of millions of lawn mowers, snow blowers, chain saws, leaf vacuums and other small, gasoline-engine-powered devices are emitting high levels of carbon monoxide, hydrocarbons and nitrogen oxides.

For example, a typical push lawnmower, according to the EPA, emits as much hourly pollution as 11 cars. To combat this, the EPA is implementing new rules to cut hydrocarbon and nitrogen oxide emissions from small gasoline engines. Similar rules are being implemented in other developed countries.

Closed-loop electronic ignition and fuel injection controls are an absolute necessity for meeting the new rules at an acceptable cost.

That's only the beginning. As auto-centric as we are in the U.S., we forget that most of the rest of the word does not travel by car. The Third World travels on two wheels, on scooters, mopeds or motorcycles which are popular even in other developed countries. Those vehicles are produced in huge volumes with little or pollution control. Worldwide motorcycle production is approaching 50 million units annually, with more than 75 percent of that production coming from China, India and Indonesia.

They may not be Gold Wings or Harleys--passenger cars on two wheels--but in the Third World, 150-cc scooters, mopeds and motorcycles are basic transportation. They're prime markets for ECUs.

Over the last three decades the semiconductor industry has made a major contribution to improving automobile performance while cutting air pollution. But there's more to do. The same thing needs to happen for all the small gasoline engines providing recreation and convenience, and for all the two-wheeled and small four-wheeled vehicles providing basic transportation. Semiconductors also can help improve performance, increase fuel economy and decrease pollution in those applications.

A little motorcycle buzzing across the Bonneville Salt Flats may have shown the way.

—Morry Marshall is vice president of strategic technologies at Semico Research Corp.
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