Hours before most commuters start their engines and head to work, James Hughes is already calling the other side of the world from his office in Dearborn, MI. Because of a six-hour time difference between most of his engineering sites abroad, including the Ford Merkenich small car center in Cologne, Germany, many of his meetings begin prior to 6 am ET.

The performance of a Chevrolet Cruze is tested on GM’s noise and vibration dynamometer. N&V requirements differ from region to region to meet customer expectations, and dictate the bandwidth of performance across a global architecture.

Hughes is the North American Focus Chief Engineer and works with the Ford Motor Company’s (www.ford.com ) C-car platform. His global technical review meetings, usually about an hour and a half to two hours, are often spent discussing regional automotive design requirements, ranging from heater performance to steering compliance. To communicate with the international teams, Hughes zooms in on vehicle components using wall-sized screens and sophisticated cameras. The team frequently discusses product proposals that meet a particular country’s mandates and preferences. The goal: to fine-tune Ford’s global car platforms.

Today’s cars require variations for different markets. A car may be too small for one segment, too wide for another, not fuel-efficient enough for a third, or not luxurious enough for the upper crust of a particular region. Once variety is introduced, however, the cost in labor and parts skyrockets.

Car manufacturers, like Hyundai with its Sonata and General Motors Company with its Chevrolet Volt, have therefore used more universal, cost-effective architectures to penetrate global markets. OEMs have been making a concerted effort to synthesize variety while using standard parts and subsystems.

In Ford’s case, the underbody, the chassis, wheels, transmission, power train, and some of the underbody sheet metal are the basis of various vehicles, and that platform can be fit with many different Ford “top hats.” A “top hat” could be a small SUV, for example.

The platform for the Chevrolet Volt, similarly, has been developed for various segments around the world, and its engineers have tweaked brake expectations and durability requirements for the urban environments of China, the rough roads of Brazil, or the increased contaminants in rural areas of India.

Hughes will help Ford as it plans to build global platforms beneath various vehicles. Its small B-cars, like the Fiesta, have a universal architecture, and Ford is currently launching a line of global C-cars, including the Focus and C-MAX.

The Next Important Design Skill? Communication

As Director of GM’s Global Noise and Vibration Center, Sheri Hickok rises early, too, and knows the challenges of working with teams around the world. GM (www.gm.com ) has 12 engineering centers, ranging from product localization to full platform development. Of these dozen, five main facilities work on GM’s eight platforms. Hickok is in frequent contact — multiple times per week — with the centers in Brazil, China, Korea, Germany, Australia, India, and the United States, discussing a region’s requirements as products are developed.

According to Hickok, the company’s push for global platforms began officially in 2006. “GM took a look and said, ‘We have all of these individual platforms around the world, even within one region.’” GM has made an effort to have multiple platforms that play across common segments, the Chevy Volt included. Several vehicles, like the Buick Lacrosse and the Chevrolet Cruze, are built off of universal frameworks, including the Epsilon platform, and sold around the world. The Cruze, said Hickok, sells in over 60 countries.

To create a global design, Ford must understand various regions’ vehicle safety standards. The WorldSID dummy, a single, universally accepted test device used by Ford, allows side-impact testing for any regulation around the world.

On one hand, day-to-day design work doesn’t change with a global car. A designer still has to perform the standard systems engineering, concept, and detail work. With global cars, however, teams need to dedicate resources to research a region’s preferences and requirements.

“It’s not just, ‘What do I need to do for my local product in the U.S.?’ anymore. It’s ‘What does the Korean market need? What does the China market need?’” said Hickok. Korean and Chinese drivers, for example, may want aggressive brakes because of the prevalence of city driving, she added. Or the noise and vibration needs may differ in areas like Brazil and India, where the terrain is rockier.

“We were finding that the region that was designing the product was designing for what they thought the customer wanted in the other regions, not for what the customer actually wanted. That was one of the biggest complexities,” said Hickok.

Hughes said Ford faced similar concerns at the onset of its common platform initiative. “Typically, historically within Ford, there were different regional requirements for certain attributes or parts of the vehicle. One of the biggest challenges we’ve had early on was to come to some type of globally recognized acceptance criteria for the part,” he said.

It was a complicated task, for example, to create a global design that could accommodate the differing crash performance requirements from both Europe and North America — European standards call for the crash test dummy to be securely fastened, for example — and still maintain the commonality and the same sheet metal, shapes, and lines seen on the Ford Focus, said Hughes. Even seemingly mundane objects like cupholders, which are a must-have in North America but not necessarily in Europe, pushed teams to make tweaks to a common framework.

Engineers of global cars also have to contend with a variety of regulations that differ from region to region, but still impact a particular vehicle framework. End-of-life vehicle (ELV) directives in Europe, for example, require safe depollution of cars before the bodies can be recycled. The European Union’s RoHS Directive similarly bans placement of electronic equipment containing more than designated allowable levels of lead and other harmful elements. Engineers also have to satisfy North America’s National Highway Traffic Safety Administration, which has stringent standards for the documentation of design traceability related to occupant safety.

Balancing requirements on a global platform calls for constant communication between the regions executing and selling the products. “I just had a face-to-face with all of my global noise and vibration leaders last week, and they had never met each other, many of them, in over ten years of working together, and what you could accomplish in four days in a room versus years over the phone was drastically different,” said Hickok.

Analytical Modeling Before Going Global

When a new product is initiated, like the next-generation Buick Lacrosse off of the Epsilon platform, Hickok brings together the relevant regions and gathers inputs for noise and vibration. They then set requirements, called technical specifications, which engineers will reference as they create their designs.

After technical specifications like Hickok’s have finally been created, analytical, model-based tools can tune a design for variations. Saving money on creating expensive prototypes, engineers may write an executable specification model that simulates and validates that requirements actually meet customer expectations. Then requirement-based tests can be written based on those created functional models. An engineer may write an executable specification model for a particular component such as a body controller, a smart power distribution junction box, or a seat controller.

An image from MathWorks displays a range of electronics on a vehicle, many of which have to be calibrated, including powertrain, steering, and ride/suspension controllers.

Global platforms require a greater emphasis on systems-engineering and requirements management, according to Marc Halpern, Research VP at the Stamford, CT-based analyst firm Gartner Inc. “You need, through your systems models, to be able to identify the critical design parameters, and how those interact with other parameters across subsystems and parts, in order to be able to design a truly global car.” Along with the systems engineering, he added, is the role of requirements management in addressing environmental, economic, safety, or ergonomics targets.

Jon Friedman, a former automotive engineer and current industry marketing manager for aerospace, defense, and the automotive industry at the Natick, MA-based mathematical computing software company MathWorks (www.mathworks.com ), says executable model-based design assists engineers looking to satisfy those different preferences. The tools allow teams to create a generic algorithm that can be tuned for local markets, and then verify that the given embedded system functions properly.

If a platform’s suspension works well everywhere except in Brazilian markets, where the roads are rockier, or if an engine controller needs to be fine-tuned, engineers can explore what Friedman calls the “outer performance envelope” of components, and then work to determine the authority of the tuning component to make sure that they can meet a wide variety of performance goals.

“For a suspension, an engineer might want to determine how much of that suspension system, that shock absorber, is tunable. Can it be both soupy and tight? Those characteristics can be modeled inside of a mathematical modeling tool and can be analyzed at a system level to determine whether overall the vehicle behavior on the edges of the performance envelope will meet the local market requirements,” said Friedman.

Hickok calls analytical models the “life blood” of the early design process, and a way to ensure that the right content is specified for the architecture before hardware is built.

If a major critical design issue is found in a created hardware component, like Hickok’s suspensions, it is often too late to implement a change in the math to impact vehicle builds and still meet the start of production without significant risk.

Hickok emphasized that models are often most critical as products are slowly rolled out. “As we launch in one region and the remaining programs follow over some pre-determined cadence, you may not see hardware representative of the ‘India’ product, for example, until long after you’re nearing production for the lead program, so changes found in hardware for India will be challenged to find their way back into the architecture without putting all program variants at risk.”

Once engineers move from design to implementation, models made from analytical tools like MathWorks’ Simulink can automatically generate code: both code to run prototype and code for production. “A lot of the cars today run production controllers with code that was automatically generated from mathematical models,” said Friedman.

The Importance of Software

Halpern believes that on-board software has become a game-changer for global cars, because of its ease in allowing variation. GPS and vehicle security features, for instance, enable communications and connectivity regardless of location. Software, he said, enhances variation of vehicle function depending on local market preferences.

“Imagine on your speedometer or tachometer, if you want text in French versus Italian or English. It’s much easier to enable text or even voice preferences via software than it would be to have physical parts with printing in different languages.”

The auto industry is also increasingly working to standardize a vehicle’s software infrastructure, bringing more plug-and-play ideas into the way embedded software is deployed in standard features, including headlight control and windshield wipers. AUTOSAR (Automotive Open System Architecture), an open and standardized automotive software architecture developed by automobile manufacturers, suppliers, and tool developers, aims to create one common standard for electronics and software in vehicles.

“[Engineers] have to really rethink the growing role of software as part of a car platform, and whatever they’re designing, how much of the function of what they typically design is going to be in the future addressed by software,” said Halpern, adding that the Chevy Volt, according to media reports, contains at least 10 million lines of code.

Converging on Car Design?

So does day-to-day engineering change when you’re working on a Chevy Volt or a Ford Focus platform? The work itself doesn’t change, perhaps, but the teams, and how they collaborate, do. Engineers have to keep an eye on particular regional requirements, and find better ways to communicate with their global teams.

“I will say the biggest challenge we’ve had is launching this one product in multiple regions at the same time, so it’s not really the engineering of it, it’s the logistics of launching one vehicle in several different locations simultaneously,” said Hughes.

Hughes noticed, however, a growing convergence on global automobile priorities and attributes. “Thankfully, the world is coming to more of an alignment and consensus on requirements, and the regional differences, as we go along every month and every year, seem to be evaporating.”

NASA Tech Briefs Magazine

This article first appeared in the March, 2011 issue of NASA Tech Briefs Magazine.

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