The Senku's body-side sheet metal has the optical illusion of "flame surfacing" similar to the BMW Z4. But the apparent concave-to-convex sheet metal bending is actually two convex surfaces joined at a crease. By doing that, the car's rocker panel area swoops under the car more dramatically, Iwao said.
"We needed tension in the side panel. The engine is behind the front axle, so we needed to show the energy coming out of the car. That's why there is no negative (concave) panel," Iwao said.
Jim Hall, an analyst with AutoPacific in Southfield, Mich., said here that there are two ways to design a design-theme car. One is as a sheet metal sketch, which bears no resemblance to anything in the lineup. The other is as a theme car, which shows a deliberate and obvious direction toward an existing vehicle. The Senku is a sheet metal sketch, Hall said.
"The Senku has a lot of ways it can be interpreted," Hall said. "It gives latitude for designers in the future, but how much of this ends up in actual cars depends on the vehicle type and positioning. We'll probably just see a part here and a part there."
James B. Treece contributed to this report
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