DETROIT – Defining a brand image for the interiors of the cars and trucks they sell can be a daunting task for auto makers.

Consumer tastes vary widely depending on where they live, and what works in one country doesn’t always work in another, say panelists at the Ward’s Auto Interiors Show here.

Chip Wilkerson, product development manager for Saab Automotive USA, says his brand likes to rely on its Swedish heritage for the exterior and interior of its vehicles.

However, when Saab presented a Scandinavian-inspired interior, with trademark light woods and clean lines, to a clinic of U.S. consumers, they “hated it,” Wilkerson says.

Ralph Risse, marketing and business development manager-Rhodia Technical & Consumers Fibers, says a big trend in Europe right now is the use of fabrics in such unorthodox places as dashboards and shift knobs.

“Today the sensory aspect of materials is quite important,” he says of the trend, although he’s not certain whether it has potential in America.

These are just two examples of the difficulties faced by auto makers trying to catch buyers’ eyes while keeping costs under control.

All of the panelists agree the cars of today have highly advanced interiors, as the number of features and electronic complexity has multiplied rapidly in the past decade.

Eelco Spoelder, vice president-infotainment solutions for Siemens VDO North America, foresees demographic shifts and increasing urbanization bringing significant changes inside the world’s cars and trucks.

“The number of mega cities will (increase) above the number of 30, meaning (a city) exceeds 10 million inhabitants,” he says. “By 2010, more than 50% of the world’s population will be living in mega cities.”

Traffic congestion will be significant if this holds true, and Spoelder says it presents an opportunity for further exploration of in-car entertainment options. He points to Japan, where there are numerous congested urban areas and the trend of in-vehicle video casting has taken hold.

“In the past, we just listened to the radio, and we will continue to listen to the radio,” Spoelder says. “But there is much more (available for entertainment).”

Panelists say they are not sure if a trend toward environmentalism will gain ground in vehicle interiors.

Honda Motor Co. Ltd. recently announced it has developed a plant-based “biofabric” to be used on its upcoming dedicated small hybrid-electric car. Prompted in part by regulations, most auto makers have worked toward cutting down on the amount of difficult-to-recycle plastics and those that emit harmful fumes in their vehicle interiors.

But Wilkerson says that Saab research shows “consumers (aren’t) opening their wallets to spend on ecology.”

An environmentally focused interior “is what people would expect from a Scandinavian brand,” he says. “But the question is how much money to put into it.”

Meanwhile, Wilkerson says some of the interior features of the Aero X concept vehicle, shown at this year’s Geneva auto show, eventually will trickle down to Saab production models.

The 400-hp, 2-seat super car has unique, prismatic-like cut-acrylic “clear zones” that use 3-dimensional graphics in place of conventional gauges.

Wilkerson won’t say specifically if the cut acrylic, which was inspired by a lineage of Scandinavian glass makers, will be seen in a future production model. But he admits Saab “definitely has some of the concepts of the Aero X coming in future vehicles.”

cschweinsberg@wardsauto.com