Nowadays, adaptive headlights have become an indispensable part of the option lists of many car manufacturers, but headlights that turn into bends go further back in time than you might think. In this edition of De Vluchtstrook we shine our light on the history of this special headlight technology.
Lighting is an important source of automotive curiosities. Earlier this section was about the yellow headlights in France, UV light in headlights and the clicking of the turn signal. Speaking of indicating direction: this does not necessarily have to be done with a standard flashing light. Anyway, when you turn into a corner at night, static headlights only illuminate the area directly in front of the car. It is difficult to have a good view of the rest of the bend. People encountered this problem early on, especially when the lighting of cars was not yet so good.
Preston Tucker at the Tucker Sedan.
Already at the beginning of the 20th century, the possibilities of making lamps turn with the bends were studied. The American William Meeker reportedly filed a patent describing such a system in 1913. Countryman Preston Tucker, however, was the first to implement a rotating headlight in a car from the factory. The Tucker 48, also unofficially referred to as the Tucker Torpedo, had a center headlight connected to the steering gear. If you moved the handlebars by more than 10 degrees, the headlight in the middle turned to a certain point. Quite an inventive system, were it not for the fact that Tucker went down in 1948. In the end only 50 copies of the Tucker 48 rolled off the production line.
On a bigger scale
After that, the idea of ​​the revolving headlight remained for a long time, partly due to the fact that American legislation prohibited this system at the time. In the end, it was Citroën that resumed the concept in 1967. On the DS III, the brand introduced rotating headlights. The big external difference with the DS II was that the headlights were now behind glass. The outer headlamps of the DS III remain straight, but the inner headlamps – those for the high beam – turn with the steering wheel up to an angle of 80 degrees thanks to a cable. The headlights turned at a slightly wider angle than the steering angle to quickly illuminate the corner. Incidentally, the outer headlights of the DS III also had automatic leveling.
The Citroën SM.
Citroën was the first manufacturer to market the revolving headlights on a larger scale. She also had the later SM from 1970 on board, but the technology behind it was a bit more complex with that model. The headlights of the SM rotated because of a hydraulic system. Ingenious, but not completely without problems. The fluid in the system could leak, causing the headlights to turn inwards and the SM to look ‘cross-eyed’, as it were. The cable system of the DS also had its troubles, because the cables had a tendency to rust in the housing. In America, however, the Citroëns got fixed headlights because the legislator still did not allow the rotating headlights. As an alternative, many more luxurious Americans received cornering lights in a separate unit in the side of the car, so that an extra lamp illuminated the corner when entering the corner.
More and more advanced
Where the headlights of the DS and SM were still operated with cables and hydraulics, it then went electronically. It wasn’t until much later that other manufacturers came up with it. Mercedes-Benz, for example, only implemented the technology for the first time in the W220 generation of the S-class, and BMW did not follow suit until the beginning of the 21st century. Later, the rotating headlamps became a more common option.
Today’s LED headlights can no longer be compared with the ones from the past. Not only do they shine light in the bend, but they also sometimes have adaptive high beam that shines around the oncoming car. Audi was the first to introduce these matrix LED headlights. Naturally, the precise operation differs from manufacturer to manufacturer. In addition, many cars now have some form of cornering lights where the fog lamp illuminates at a certain degree of steering input to provide better visibility.
Below you can see the rotating headlights of the DS III in action!