Perceptual attributes in product design: Fuel economy and silhouette-based perceived environmental friendliness tradeoffs in automotive vehicle design

The quest for improved fuel efficiency and environmental friendliness is transforming automotive vehicle design. In addition to new energy sources and management, new powertrain technologies offer increased flexibility in the spatial arrangement (packaging) and exterior shape (styling) of a vehicle. Design choices in packaging and styling are closely linked to consumer preferences, particularly those that influence consumers' decisions about the objective qualities of a product (i.e., perceptual attributes). The ability to include perceptual attributes into a design optimization study is a valuable extension of the more traditional engineering approach that looks at only functional attributes. Previous work has studied the quantification of perceived environmental friendliness (PEF) in vehicle silhouette design. In this paper, empirically validated PEF silhouette attributes are included as constraints in a vehicle optimization model that maximizes fuel economy. Results indicate that there is a tradeoff between PEF preferences and the attainable fuel economy for a given vehicle, where increasing vehicle length leads to increasing PEF and decreasing fuel economy.