Adaptive brake lights: Effective warning of rear-end collisions

Apr 12, 2006
  • Standard equipment on the new generation E-Class
  • Braking distance reduced by over four metres at 80 km/h
As with the airbag, seatbelt tensioner, ESP® and other pioneering Mercedes safety systems, the development of the adaptive brake lights and Brake Assist also focused on the types of accidents that commonly occur under real conditions. More specifically, the researchers took into consideration the high number of rear-end collisions, which account for over 17 percent of all traffic accidents that result in fatalities and injuries in Germany.
In the USA, rear-end collisions account for 31 per cent of all accidents that result in deaths and injuries, according to statistics from the National Highway Traffic Safety Administration (NHTSA).
Flashing brake lights can contribute effectively to preventing these kinds of accidents. Studies carried out by Mercedes engineers show that drivers’ braking reaction time can be shortened by up to 0.2 seconds on average if a flashing red warning light is substituted for a conventional brake light in emergency braking situations. As a result, the braking distance can be reduced by 4.4 metres at a speed of 80 km/h, and by as much as 5.5 metres at 100 km/h. Flashing brake lights are therefore an effective means of preventing rear-end collisions. This technology means motoring also becomes safer even for those road users not driving a Mercedes-Benz.
The Mercedes experts tested various types of hazard lights for their study. Brake lights that flash four times faster than yellow hazard lights proved to be particularly effective in warning drivers of a possible rear-end collision. The Mercedes study also revealed that activating the hazard lights in dangerous situations had only a minor effect on drivers’ reaction times.