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Extending the Benefits of ESC



In 2005, the automotive industry celebrated 10 years of manufacturing a technology that proved invaluable for increasing passenger vehicle safety. Electronic stability control (ESC) first came to market on the 1995 Mercedes-BenzS-Class. Since being introduced, ESC has received numerous accolades for its ability to reduce vehicle crashes by decreasing skidding and improving vehicle stability. Most recently, the National Highway Traffic Safety Administration (NHTSA) confirmed ESC's significant role in passenger safety, indicating that the technology reduced fatal SUV crashes by 67%, and fatal car crashes by 35%.

An important aspect of ESC is its ability to work in conjunction with other safety applications. Rollover mitigation (ROM) is one example of this flexibility at work. Through existing ESC sensors, ROM can help reduce rollover risk by determining when a vehicle is experiencing extreme lateral tire forces, and activate to reduce those forces. Additionally, trailer sway mitigation uses existing ESC system components to prevent unstable oscillations and trailer sway through brake interventions on the tow vehicle.

Looking further into the future, it is evident that ESC will serve as a gateway for other important safety systems. The range of data ESC provides can significantly influence the performance of technologies such as adaptive cruise control (ACC), airbags, collision mitigation, and automatic emergency brake systems. For example, while ACC can theoretically function without ESC, when ESC data is provided, the performance and benefits of ACC are expanded for the driver. Specifically, ESC provides an increased deceleration capability through active braking without sacrificing vehicle stability. Additionally, in the event of an emergency braking situation, ESC allows the vehicle to maximize braking, which in the future will assist collision-mitigation technologies in avoiding an accident or at least minimizing the effects of a collision.

Likewise, as ESC helps to maximize braking scenarios, it can also interact with airbags to result in more effective deployments. ESC has the ability to act as an early indicator, communicating to the airbags that a vehicle is in an unstable condition (such as sliding sideways). By pre-arming the airbags with more comprehensive data, the airbags are then able to deploy more quickly and accurately.

Not only does performance improve when controllers from one system are able to communicate with controllers of another system, but this interaction also provides a way to reduce costs for automakers; further reason for the industry to become involved in initiatives such as Automotive Open System Architecture. Defining a worldwide industry standard for basic functions and interfaces in every automotive electronic control unit is a necessity to ensure the effective application of these future, system-to-system interfaces. This common standard is also the only way the industry is truly makes the shift from thinking about vehicle safety in terms of crash worthiness to thinking about it from the perspective of crash avoidance, which ultimately saves more lives. And ESC is a key starting point for this growth in system-to-system interface.

BMW’s Drivetrain For Tomorrow

One of BMW's core competencies is the development of combustion engines. During recent years BMW has significantly reduced both fuel consumption and emissions in its engines, while simultaneously increasing performance and torque. The latest milestones from these efforts are the first-ever variable twin-turbocharger diesel power unit in a road vehicle, making its debut in the new BMW 535d, and the new BMW six-cylinder gasoline engine with 12% increased power and 12% less consumption. In the future, the introduction of spray-guided direct injection and the implementation of " lean combustion" will bring consumption in the gasoline engine closer to the values attained by modern diesel units.

An important component in developing drive technology lies in intelligent electric power for the drivetrain, for example through an " active gear" combined with high-performance capacitors. The function of an intelligently honed drive is to intervene electrically in the drivetrain and optimize driving situations like stop-and-go traffic or acceleration. However, all concepts geared towards intelligent electrification remain no more than an auxiliary solution for the internal combustion engine.

As shown in the BMW X5 experimental vehicle, an electric motor between the internal combustion engine and the gearbox supports the conventional drive during acceleration efficiently. The research vehicle was presented in 2003 and produced responses that had never been attained before, while also increasing torque to 1000 N-m (740 lb-ft) in the lower range. More important, the vehicle also reduced fuel consumption by up to 15% in the driving cycle compared to the conventional powertrain.

Over the long term, hydrogen is thought to be the fuel with the greatest potential for sustainable mobility in the future. BMW Group specialists are permanently working on improvements of the hydrogen combustion engine. Already, by setting nine records and reaching a top speed of 302.4 km/h (185.5 mph) with the BMW H2R research vehicle on September 19, 2004, the BMW Group has clearly proven its conviction that hydrogen is able to replace conventional fuel without requiring the driver to make compromises in terms of up-to-date dynamic performance.

The reliability and durability of the technology used clearly demonstrates the capability of BMW Group in developing the hydrogen engine to production standard. In this process, BMW is concentrating on the combustion engine simply because the combustion power unit, given the sum total of all its features and characteristics, still offers the largest number of advantages and benefits all in one.

BMW's future hydrogen engine for its premium saloon will be built for dual-mode operation. BMW will be launching a dual-mode version of the 7Series during the production cycle of the present model, thus introducing the first car of its kind able to run on both hydrogen and gasoline.

The Diesel Solution

The future of commercial vehicles is a subject that we at Navistar International focus on every day. In fact, it's our core business, as we are the nation's largest combined commercial truck, school bus, and mid-range diesel engine producer.

Today, I'm more convinced than ever that focusing on diesel was a smart decision, and that the leading engine technology for the foreseeable future, indeed for the 21st century, will be diesel.

We listen to our customers, and they tell us what they need. The companies who listen better tend to do better. The reason we chose diesel over gasoline was that our customers believed in diesel and understood its advantages, including:

•A longer driving range without refueling

•40 to 60% better mileage than gasoline, due to greater fuel efficiency

•Durability, since diesel engines typically last at least twice as long as gasoline engines

•Performance, with torque that is 30 to 50% higher than gasoline engines

•Increased safety, with reduced risk of flammability

•Extended idling capability, which is one reason virtually all ambulances are diesel.

The challenge is the perception that diesel is " dirty, " an image many people still have. But in fact, we aren't making smoky trucks anymore, and haven’t for many years. We introduced a smokeless engine in 1989, and haven't looked back since.

The reality is that today's diesel has 98% lower emissions than it did before regulation, and we have led the way in demonstrating that diesel engines in trucks and school buses can be as clean or cleaner than engines powered by any other fuel. Our company's path to low-emitting diesel technology is called International Green Diesel Technology, which combines efficient, high-tech engines that use fuel even more efficiently (and actually start the emissions clean-up in the cylinder); advanced aftertreatment that captures and burns emissions before they escape; and ultra-low-sulfur (ULS) diesel fuel that lets the aftertreatment work, similar to the way that removing lead from gasoline enabled catalytic converters to work in passenger cars.

In fact, diesel has already proven to be the preferred solution for consumers, business, environmentalists, school districts, and the military. From school buses to ambulances to an increasing number of passenger vehicles, the vehicles that people depend on are diesel-powered.

Diesel is already the solution for virtually all heavy-duty trucks and almost all medium-duty trucks. Heavy-duty pickup owners are now switching to diesel. With the technology and new fuel widely available, this trend will include diesel in SUVs and light pickups. In the U.S. and Canada, we are on the way to what they are doing in Europe, where roughly 50% of new cars are diesels.

Diesel offers the U.S. the opportunity to save on both fuel economy and emissions. As to fuel economy, the Department of Energy estimates that if light-duty diesel achieved only 30% of its market potential—not 50% as in Europe—by 2020, we'd save 700, 000 barrels of oil a day, or one-half the daily energy use of California. By my rough estimate, that translates to over half a billion pounds of CO2 a day—more than 200 billion pounds a year.

At the national policy level, diesel offers immediate advantages over any other power source. New low-emitting diesel vehicles (such as school buses) are just as clean, if not cleaner, than those using natural gas. Hydrogen fuel cells sound exciting, but are decades away. By contrast, within a short time frame, diesel offers our nation the following opportunities:

• To reduce our cost per mile traveled

• To reduce our imports of foreign oil

• To reduce CO, emissions.

When you consider all these advantages, it's clear that the public and national interest stands to benefit from America's strengthening its commitment to low-emitting diesel vehicles. Yet as matters currently stand, the highest costs of making this move will fall on the truck and bus customers who buy new products in 2007.

That is why I believe government needs to do everything possible to provide incentives to help commercial vehicles make the transition to low-emitting diesel. We need to help people in the trucking business today make their purchase commitments for 2007. And we need to accelerate the trend toward diesel, which is in the long-term national interest. I am confident that the marketplace will make the right decision—as it did after we placed our bet on diesel in the mid-1980s.


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