Reflective material on the body and tyres could further improve the lateral visibility of vehicles, and help to avoid accidents at road junc-tions.

Reflective materials have long been commonplace in children’s clothing, and in the case of bicycles it is even mandatory to have reflectors in the wheel spokes. So the engineers at Mercedes-Benz asked themselves why the perceptual safety of cars could not be improved in the same way. Ac-cordingly the ESF 2009
research car features appropriate reflective elements when viewed from the side. These modifications are not visible during the daytime, but the addi-tional benefit shows up when dusk and darkness fall.

Together with the manufacturer Continental, Mercedes specialists have de-veloped a reflective strip on the tyres which visually enlarges the wheels in daylight and creates an easily visible band of light when illuminated at night. As a further safety feature there are reflective seals between the doors and the roof, a joint development with the adhesive foil specialist 3M. The aim is to make the vehicle’s silhouette more easily visible in the dark. This enables potential accident situations on junctions or in the form of unlit, parked vehi-cles to be defused.

Reflective foils consist if a reflective base layer with tiny balls of glass. When a ray of light hits the foil, it is refracted by the glass balls, reflected by the base
layer and refracted again on exiting. As a result, most of the light is reflected back in its original direction.