Mercedes-Benz was the first automaker to debut collision preparation technology in 2002, but has been working on such systems for two decades. The first fruits of the company’s labor appeared as protective roll hoops for the 1989 SL roadster, which exploded into place behind the rear seats in the event of a rollover accident. Today, the SL continues to offer this protective device, as well as the CLK cabriolet. In fact, we’ve experienced this roll hoop deployment personally, while tooling along the Pacific Coast Highway near Big Sur, where rapid speed on a twisty road with sudden elevation changes caused a current-generation SL to figure we were about to do something stupid.

We haven’t seen Pre-Safe in action, but it works similarly to those developed by Acura and Lexus, with subtle but effective differences. Like the competitors’ systems that came after it, Pre-Safe relies on radar to work, but uses two beams rather than one to determine the rate of approach of objects in front of the vehicle. When Pre-Safe determines that a collision is imminent, it removes slack from the seatbelts by activating the pre-tensioners, and readies the brake assist system to activate full braking pressure when the driver jams on the pedal. But Pre-Safe goes a couple of steps further. If the front passenger’s seat or the rear power seats are reclined, moved too far forward, or otherwise out of optimum placement for protection, they are automatically moved into a more favorable position. Pre-Safe will also close the sunroof if the vehicle skids, since a skid is often a precursor to a rollover accident.

Currently, Pre-Safe is offered on the flagship S-Class sedan, where it is standard on every model, from the $65,675 S350 to the $169,775 S65 AMG. When the all-new 2007 Mercedes-Benz S-Class debuts, Pre-Safe gets enhancements that will close any open side windows to make better use of side curtain airbags, and will inflate special seat cushions to position occupants properly before impact. There is no plan to offer automatic braking, like Acura’s CMBS.

Photos courtesy of the Manufacturers