ArvinMeritor may have exited the light-vehicle business (only the Body Systems unit remains to be divested, which should occur by year-end), but it has not abandoned the wealth of knowledge and engineering expertise acquired from that segment.
To achieve positive results in its “three key areas of innovation”—fuel efficiency, safety, and durability—the commercial-vehicle supplier is not only investing in engineering and R&D; it is also drawing heavily upon its previous work on the light-duty side, Chip McClure, Chairman, Chief Executive Officer, and President of ArvinMeritor, shared at the annual SAE World Congress breakfast sponsored by the Detroit Regional Economic Partnership.
“Of course, these are some of the same issues that must be dealt with in the passenger segment,” McClure said. “In some areas we lead the light-vehicle market, and in other areas we have adopted their technology and applied it to our engineering research and development for commercial vehicles.”
For example, when divesting its Light Vehicle Systems, ArvinMeritor decided to retain the Smart Systems development group to help accelerate the company’s electronics and controls capabilities. “As we add ‘intelligent systems’ to our products, we can apply the experience and know-how from our light-vehicle engineers,” he said. Active damping control for suspensions is one technology that has transferred from the light-vehicle business: “We’ve actually incorporated it into some of our applications on the military side and we’re looking to do so on the truck side.”
To drive home the significance of improving fuel efficiency in commercial vehicles, McClure noted that it takes 48 cars to match the annual fuel use of a typical line-haul truck, traveling an average of 120,000 mi (193,000 km) per year. Heavy-duty vehicles even consume more than four times the amount of fuel per year than medium-duty trucks, of which there are “significantly more” on the road.
“Our engineers are working hard to find ways to improve commercial-vehicle fuel consumption by 10 to 20%,” he said. “They’re researching and developing technologies that will cut parasitic losses, improve energy efficiency, and reduce weight.”
One example McClure stressed is development of the company’s dual-mode hybrid drive system, which began testing with Wal-Mart’s commercial fleet over a year ago. The system is designed to operate as a hybrid in city driving, he explained, and transition to parallel driving at highway speeds.
Production of the dual-mode hybrid is expected in 2013.
“Bottom line results mean that while a hybrid passenger car saves 138 gal of fuel a year, a Class 8 hybrid truck saves over 3000 gal. That’s the equivalent of taking seven cars off the road,” McClure said. “Due to their duty cycle, commercial vehicles actually provide a better payback scenario than passenger cars. Depending on the drive cycle, fuel-consumption improvements can be as high as 20%, with a targeted payback of less than three years.”
The heavy-duty hybrid is another technology that has benefited from ArvinMeritor’s Smart Systems group. “It truly is similar to what you do on the car side, it’s just a whole lot bigger,” McClure told Automotive Engineering International at a roundtable with select media following the SAE World Congress breakfast. “You’ve got a lot of the same kind of electromechanical interfaces.
“The challenge you have on the commercial-vehicle side as opposed to the car side—aside from the obvious, that the batteries have to be bigger—is that you’re out in the environment. Batteries in a car tend to be in the trunk or under the rear seat; these tend to hang on the rail of a truck, so you’ve got to make sure that they have proper ventilation but also are protected from the elements of the road.”
Hub-and-spoke operations, where vehicles depart for the day and return at night, are an ideal application for hybrid, plug-in hybrid, or even pure electric technology, McClure noted.
“On the Class 8, it’s really going to depend on the application. Long, over-the-road applications are very efficient at highway speeds, so we’re spending a lot of time lightweighting our products, getting rid of parasitic losses, providing efficiencies in the current internal-combustion engine,” he explained. “But a lot of these same over-the-road tractors are used for pickup and delivery within the city, and there could be application there. So I think it’s going to be a combination of both at the end; hybrids will have an appropriate niche.”
While he admits that such game-changing technology is exciting, “incremental improvements that can add up to quick, significant savings” are necessary as well. Reducing component weight for heavy-duty vehicles is a key trend, just as it is on the passenger-car side. But also similar is the fact that any lightweighting advances are oftentimes offset by an increase in content.
In passenger cars, that content includes additional creature comforts that consumers have come to expect from new vehicle models, which are also usually longer, wider, and taller than their predecessors. On the heavy-duty side, the reason for increased content is more pragmatic: to meet emissions regulations.
“Heavy-duty vehicles had over 400 lb of emission components added in 2007. Then another 400 lb more of emission content this year,” McClure explained. “End result is we’ve seen the same creep as light vehicles in overall weight.”
Commercial-vehicle customers have an added incentive to reduce vehicle weight: “It allows them to make more money,” he said, by enabling an increase in payload.
“There is such a demand to reduce component weight, that NHTSA may develop fuel-economy standards for heavy trucks not just on miles per gallon but on ton-miles per gallon,” McClure said. “In other words, how much fuel is used to transport one ton of freight. It makes sense; it’s good for the country and the industry.”
Materials are an obvious consideration when looking to cut out weight. Beyond more aluminum usage, will plastics or other “exotic” materials become more commonplace on Class 8 trucks for this purpose? “Maybe” was McClure’s reply, noting that the customer’s perception of a material is just as important as the material’s performance—even if it meets specification.
“Suffice it to say that in the trucking industry, they like those big axles, those big suspensions, big brake systems; you’ve got to get them used to understanding [the benefits of] plastics or titanium or other materials. A lot of them understand iron is iron, and they want it that way,” he said. “But I don’t rule out anything.”