Comprehensive driving safety: Innovative answers to new challenges
Automated cars such as the ESF 2019 bring the vision of accident-free driving a bit closer. However, is the era of automated and autonomous driving, we need a comprehensive safety concept with many innovative solutions, as passengers might be seated much more flexibly in the interior than they are today.
The ESF 2019 adapts itself to the situation: when it is driving in fully-automated mode, the steering wheel and pedal cluster are retracted. Together with the level, padded floor, this can not only reduce the risk of injury in a crash, but also clearly indicates that the vehicle is in automated mode.
Coordinated interaction between the seat belts, belt tensioners, belt force limiters and airbags is a standard feature of Mercedes-Benz restraint systems. As the passengers in automated vehicles might not always be in the best possible seating position in relation to present restraint systems, new ideas are necessary.
For example, the belt system has been integrated into the front seats, so that even when the occupant is in a more relaxed position, the belt fits as closely as possible. The belt system also has an electrically powered high-performance belt tensioner. This not only tensions in PRE-SAFE® situations, but is also able to respond at the moment of impact and tension the occupant's seat belt to an extent adequate to ensure that even when projected forward, he/she is pulled back into a more favourable, upright position.
The new flexibility in the interior requires new airbag systems with alternative installation spaces. In the ESF 2019, for example, the driver airbag is located in the dashboard, not the steering wheel. This deployment concept familiar from the front passenger airbag, plus the three-dimensional airbag shape this makes possible, allows greater coverage. For a better view of the instruments and displays, and to position the airbag where it is least obstructed, the steering wheel has a flattened upper section. The Steer-By-Wire technology in the ESF 2019 – in which steering commands are transmitted electrically and not mechanically – supports the new, slightly rectangular steering wheel geometry. As the steering ratio is now variably controllable, it is no longer necessary to cross one hand over the other on the steering wheel when steering. Manoeuvring, for example, requires significantly less movement of the steering wheel, even for a large turning angle.
Another completely new development is also due to the great seating flexibility: the integral sidebag, which deploys from the side bolsters of the seat backrest on both sides. The wing-shaped airbag wraps itself around the shoulders, arms and head of the seat occupant. Its special feature is that it not only protects the passenger on the side facing the impact. As a so-called middle airbag, it can cushion the occupant on the side not facing the impact (known as a far-side impact) and prevent him/her from moving too close to another front seat occupant.
Remaining fit with light from the sun visor: Vitalising interior lighting
For Mercedes-Benz, the focus is on the driver when it comes to preventing accidents. Good visibility and relaxed driving are two basic factors that have always been inherent to our vehicles. Our engineers refer to this as "driver-fitness safety".
The driver and passengers in a vehicle sit in relative darkness. Studies have shown that only around 5 to 20 percent of daylight reaches the eyes of the occupants. This can lead to a faster decline in alertness and concentration. Mercedes-Benz shows an innovative solution in the ESF 2019, with vitalising interior lighting: biologically effective, daylight-like light from the sun visor supplements the natural daylight without dazzle and keeps the body in its natural biological rhythm. This keeps the driver fitter.
Mercedes-Benz has already tested vitalising interior lighting during several studies conducted with test subjects. At the end of 2017 a team of researchers used two Mercedes-Benz Actros TopFit trucks to examine the effects of additional light on the mental state and performance of truck drivers. In addition to the vitalising interior lighting while on the move, they also examined a stimulating light shower during breaks and a vitalising light alarm in the morning. The combination of these three light programmes forms a biologically effective system. The tests showed that with the vitalising interior lighting, the ability to react remained more constant and there were fewer incorrect responses in monotonous driving conditions. More information on the study in Finland can be found here.
The vitalising interior lighting has also been tested in passenger cars as part of a scientific study: especially in the morning, the test subjects tended to react more quickly thanks to the lighting, and made fewer mistakes at the wheel. This was the result of the last study conducted in January and February 2018, using converted E-Class cars and around 40 test subjects. It was found that with vitalising interior lighting – unlike on comparative test runs without it – no warnings were needed from ATTENTION ASSIST. Furthermore, the drivers with this lighting in the vehicle tended to be in a more alert state. EEG measurements (electroencephalograms) of brain waves recorded during journeys and evaluated also confirm this.