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.