Back in 1987, Mercedes Benz was the first automobile manufacturer in the world to introduce the front airbag in a series-production car. The technology debuted in the 126 model series S-Class at the Frankfurt International Motor Show in September 1987. It elevated the safety standards in passenger cars to next level. Today after 33 years Mercedes Benz have made yet another milestone in the safety standards of passenger cars.
1. World’s first frontal airbag for rear passengers
The new optional rear airbag is the world’s first frontal airbag for the two passengers on the outer rear seats. Its design with an innovative, tubular structure is unique. As a result it deploys especially gently, and in severe frontal collisions it can greatly reduce the loads acting on the heads and necks of the outer rear passengers.
The Cylindrical, tubular structures are inflated with compressed gas and deploy a wing-shaped structure. A large, tent-like airbag deploys between the two wings, and this is inflated by the surrounding air via specially patented valves in the skin. These valves are designed so that the air cannot escape when the rear passenger is immersed in the airbag. The comparatively small volume of the tubes allows rapid deployment of a relatively large airbag volume.
This takes place with comparatively low force and a low risk of injury, as the tubular wings give way to obstacles. The airbag enhances the restraining effect of the belt system, and can support the head and neck to decrease the loads on them significantly. In combination with a beltbag and the inflatable seat belt, the S-Class sets new standards for rear seat occupant safety.
2. PRE-SAFE Impulse Side
In addition to the familiar functions, the body of the new 2021 Mercedes Benz S-Class can be slightly raised just before the collision when a side impact threatens. The side-mounted radar sensors are able to recognise and track a potential side crash at an early stage. The actuator is the E-ACTIVE BODY CONTROL suspension, which can raise the body upwards by up to 80 millimetres. This reduces the loads on the door structures, as the door sill can absorb more of the load thanks to its higher position. As a result deformation of the passenger cell and the loads acting on the occupants can be reduced.
3. Centre airbag
During a severe side impact, this positions itself between the driver and front passenger seat, reducing the risk of their heads making contact It is integrated into the driver’s seatback in the middle of the vehicle. The centre airbag is triggered when a severe side collision is recognised and certain conditions are met. The main factors for deployment are the direction of impact, impact side, and front passenger seat occupancy. This feature will be available depending on country.
4. Rear-axle steering
Thanks to the new optional rear-axle steering, now parking the 2021 Mercedes Benz S-class in tight space is easy task. With rear-axle steering and a large steering angle at the rear, the turning circle of the S-Class is reduced by up to 2 metres. This gives the long-wheelbase S-Class a turning circle of less than 11 metres. When opting for this feature, customers have a choice between two variants, one with a rear steering angle of up to ten degrees and one with up to 4.5 degrees
An electric motor drives a spindle at the rear axle via a drive belt. This makes axial adjustments to the spindle. Depending on the speed and the steering angle, the rear wheels are turned in the same or the opposite direction as the front wheels (same-direction or counter-direction steering). In simplified terms, this produces more agility and a smaller turning circle by counter-steering and more stability with same-direction steering.
In the 2021 Mercedes Benz S-Class, the full steering angle of ten degrees is especially used during parking manoeuvres. The environmental data of the vehicle sensors (radar, camera, ultrasonic) are used for large steering angles to adapt the maximum angle to the relevant situation. The system switches from counter-direction to same-direction steering at more than 60 km/h.
The different driving modes rely on different steering strategies. The respective rear-axle angles and trajectories are shown in the driving mode menu in the central display. The 10° rear axle steering has a special snowchain mode. When activated by the driver, the steering angle at the rear axle is reduced and the steering characteristics are adapted for the special conditions of surface snow.
5. E-Active Body Control
With five multi-core processors, more than 20 sensors and the use of the stereo camera, the optional E-Active Body Control suspension responds predictively to different driving situations. Adds semi-supporting hydropneumatics to the air suspension. The air springs bear the base load of the vehicle body and gradually regulate the level.
The hydropneumatics generate dynamic forces that overlay the air suspension forces, and actively support and dampen the vehicle body. At each wheel, a damper is installed within the axle whose two working chambers have an adjustable damping valve and a hydraulic pressure reservoir.
The damper is connected to an intelligent motor/pump unit in the 48 V network by hydraulic lines. Actuation of the motor/pump unit enables the hydraulic fluid to be displaced to create a difference in pressure within the damper, allowing an active force to be generated.
The motor/pump units at all four wheels are coordinated by a central control unit which also actuates the valves and the compressor for the air springs, and therefore always controls the entire suspension system.
6. New Driver Assistance Package
The 2021 Mercedes Benz S Class comes witt latest generation of the Driving Assistance Package which has new and numerous improved functions like the new Active Blind Spot Assist and Active Steering Assist. The Active Blind Spot Assist now gets exit warning function which gives a warning as soon as the driver or front passenger reach for the door.
This is because the MBUX Interior Assistant recognises when a hand approaches the door handle. A visual warning is given by a red warning triangle in the exterior mirror and via the active ambient lighting. The new Active Steering Assist feature assists the driver in forming an emergency corridor, and encourages other drivers to form a corridor as well.
7. New Parking System
The 2021 Mercedes Benz S Class gets improved environmental sensors and integration into MBUX, the parking systems give the driver even better support when manoeuvring at low speed. The new Active Parking Assist features include 12 ultrasonic sensors at the front and rear, with improved performance.
Other Active Parking Assist features include Newly developed, understandable and simplified user interface, integrated into MBUX, convenient touch control, The positions of road users and objects can be registered reliably and highly precisely, Emergency braking function when reversing, Integration of the optional rear axle steering, commensurate trajectory planning
The optional Parking package with 360° camera gets extended environmental sensors, now with sensor fusion and four additional cameras (front, rear, exterior mirrors). These enable more parking spaces to be recognised and offered. Parking spaces defined by lines (not by vehicles) can also be used for automated parking for the first time
The four individual camera images are combined into a three-dimensional image of the vehicle’s surroundings. This is shown in the central display with dynamic perspectives. The three-dimensional image can be intuitively rotated around the vehicle as a virtual camera view, and even has a zoom function
The extended side view makes manoeuvring easier near parallel obstacles such as kerbs, garage walls etc. The optional Parking package with 360° camera also gets safety features like automatic braking for pedestrians either forwards or when reversing if Parking Assist is active. Collision prevention around the entire vehicle is possible, while complying with the strict requirements of UNECE R79 for automated parking.