Mercedes-Benz has been known for being a pioneer in increased safety and better driving experience. “Das beste oder nichts”, which articulately translates to “The Best or Nothing”. Safety is an essential part of Mercedes-Benz’s DNA and one of the core responsibilities the company has assumed in regards to all road users. The priority of the brand with the star is to prevent and improve the outcome of accidents. Two anniversaries in active and passive safety serve the company as an opportunity to present its latest safety features. Everything was set off by a car test in October exactly 25 years ago. In Sweden in 1997, the A-Class rolled over during the so-called ‘moose test’. This prompted the rapid and widespread introduction of the Electronic Stability Program ESP® in all Mercedes-Benz models. The company immediately followed up with extensive development of driving assistance systems. Today, drivers of current Mercedes-Benz models enjoy many support systems. The second anniversary: Twenty years ago, the anticipatory protection system PRE-SAFE®, which has undergone continuous development ever since, was introduced. This was the first time that active elements helped support passive protective measures in order to improve outcomes of an accident. The company is pursuing a clear goal: to achieve accident-free driving by 2050. The ‘real-life safety’ philosophy guiding the company’s ambitious goal is based on real-world accidents. The Group’s own Accident Research unit, which Mercedes-Benz has been conducting for more than 50 years, forms an essential component. In recent years, research has been expanded to include locations in China and India.
Twenty-five years ago, the automotive world was in an uproar when, on October 21, 1997, the new Mercedes-Benz A-Class (W 168 series) rolled over during a spectacular test conducted by the Swedish magazine ‘Teknikens Värld’. This incident during a ‘moose test’, only known to the Scandinavian public at the time, helped the Electronic Stability Program ESP® to achieve a breakthrough, admittedly involuntarily. Only two years later, Mercedes-Benz for the first time introduced the system as standard worldwide in the S-Class Coupe (C 140 series). The company reacted immediately to the A-Class incident, upgrading all 18,000 vehicles already delivered at no cost to customers. The system became a standard feature in the A-Class from February 1998. This made Mercedes-Benz a pioneer in the industry, successively outfitting all model series with ESP® as a standard feature starting in 1999. Overnight, ESP® became a symbol for an innovative and active in-car safety system – regardless of vehicle class. Today, 25 years later, ESP® is standard equipment in all Mercedes-Benz passenger cars. And in November 2011, it even became a legal requirement for all new car registrations in Europe. ESP® also paved the way for the other active driver assistance systems available today.
Brake control systems involved in more than 100 vehicle functions
ESP® stabilizes the vehicle through targeted and lightning-fast braking intervention on individual wheels. Largely ignored by the public until now, brake control systems have continued to develop rapidly since the moose test incident. Today, these systems work in tandem with multiple vehicle functions to actively improve safety, efficiency and comfort in many driving situations, ranging from the integrated brake controller and active rear axle steering to off-road functions, recuperation for electric drives to the support of automated driving and numerous assistance systems.
Development milestones along the way include the regenerative braking system for hybrid and electric vehicles, which Mercedes-Benz introduced back in 2010. When braking, the electric motor switches to generator mode. The wheels transfer the kinetic energy to the generator via the drive train. The generator rotates, converting part of the kinetic energy into electrical energy. The braking torque that the electric motor generates when producing electrical energy slows down the vehicle. If more braking power is needed, additional deceleration is provided by the wheel brakes. The distribution between the generator and the braking system as well as vehicle stability, even in phases of high recuperation, is always managed by the brake control system.
TwoBox system for electric vehicles
One of the more significant recent innovations is the TwoBox system, which went into series production in 2020. The system, which is a combination of ESP® and an electromechanical brake booster, a crucial component for electric cars in particular, foregoes the negative pressure generated by a combustion engine that is then fed to a conventional brake booster. The system’s rapid build-up of brake pressure enables, among other things, short braking distances during automatic emergency braking.
In the plug-in hybrid S-Class, Mercedes-Benz uses the next generation of regenerative braking systems with a vacuum-independent, electromechanical brake booster. These systems switch automatically and flexibly between hydraulic braking and recuperation on a case by case basis for optimum energy recovery at all times. The outcome: the car achieves maximum recuperation power more frequently than with a conventional, purely hydraulic braking system.
Another innovation is the combination of brake control system and optional rear axle steering, which also went into series production in 2020. This novel control technology can actively adapt handling to the desired profile in the normal range as well as stabilize the car in the threshold range, while various modular actuators can accurately predict upcoming dynamics.
Mercedes-Benz and Mercedes-AMG have offered the integrated driving dynamics control and integrated traction control systems for some time now. They increase driving safety in the threshold range without taking away driving pleasure. Numerous sensors and parameters such as brake pressure, yaw torque, wheel slip and gas pedal position work in tandem to enable different driving experiences. Users can, depending on the selected driving program or individual settings, enjoy a different and completely unique driving experience without losing control of the vehicle.
Active driver assistance systems ensure safety for all road users today