The next steps on the way to accident-free driving

Oct 28, 2020

In the new S-Class, Mercedes-Benz comes another big step closer to its vision of accident-free driving. The driver is supported by numerous new or extended driving assistance systems. He/she thereby has a reduced workload in day-to-day situations, and is able to drive comfortably and safely. When danger threatens, the assistance systems are able to respond to impending collisions as the situation demands. The assistants are also ready to help when parking – see chapter "The parking assistants". The operating principle of the systems is made visible by a new display concept in the driver display.

In day-to-day driving, assistance systems relieve driver stress as the situation requires, by adapting the vehicle speed, controlling distance, steering and lane-changing. This enables the driver to stay alert for longer, and reach the destination more safely and comfortably. When danger threatens, i.e. if there is a risk of an accident owing to driver inattention or distraction, driving assistance systems can respond according to the situation and mitigate the severity of possible collisions, or even avoid them.

The S-Class has a new generation of steering wheels with capacitive hands-off recognition. There is a two-zone sensor pad in the steering wheel rim. The sensors on the front and reverse sides of the rim register whether the driver's hands are on the wheel. No steering movement is now necessary to inform the driving assistance systems that the driver has control.

The new assistance display in the driver display clearly shows the operating principle of the driving assistance systems as a full-screen view. This is where the driver of an S-Class can see an abstract view of the car, driving lanes, lane markings and other road users such as cars, trucks and bikes. The system status and operation of the assistants are visualised in this depiction of the surroundings. The new, animated assistance display is based on a 3D scene generated in real time. This dynamic, high-quality representation makes the operation of the driving assistance systems transparent as a tangible augmented reality experience.

The vehicle needs eyes and ears to perform all these tasks – its sensors. The following are on board the new S-Class with the standard Driving Assistance package:

  • Front multi-mode radar: 2 radar sensors with an aperture angle of 130°
  • Front long-range radar: 1 radar sensor with an aperture angle of 90° and 9°
  • Front stereo multi-purpose camera: 1 camera with an aperture angle of 70°
  • Rear multi-mode radar: 2 radar sensors with an aperture angle of 130°
  • 360° camera (close range): 4 cameras with aperture angle of 180°
  • Ultrasonic (close range): 12 sensors with an aperture angle of 120°

The basic functions of the systems in the Driving Assistance package can be found here. The following are the key new features of the systems in the S-Class:

Active Distance Assist DISTRONIC

On all types of roads – motorways, country roads or in town – this intelligent system can automatically maintain a preset distance from vehicles ahead. New features:

  • collision-preventing response to stationary road users at up to 100 km/h (previously 60 km/h)
  • selection of DISTRONIC dynamics in MBUX, independently of DYNAMIC SELECT

Active Steering Assist

This helps the driver to follow the driving lane at speeds up to 210 km/h. New features:

  • additional lane recognition by a 360° camera
  • significantly improved availability and performance on bends on country roads
  • improved lane centering on motorways
  • situation-specific off-centred driving (e.g. forming an emergency lane, but also following the road edge on country roads with no centre marking)

Traffic Sign Assist

In addition to conventionally signposted speed limits, this recognises overhead gantries and signs at roadworks. New features:

  • stop sign warning function – warning when about to pass a stop sign
  • red traffic light warning function - warning when about to cross a red traffic light.

Active Lane Keeping Assist

In a speed range of 60 to 250 km/h, Active Lane Keeping Assist uses a camera to detect when road markings or road edges are crossed, helping the driver to avoid leaving the driving lane unintentionally. The system also intervenes if there is a danger of collision with recognised road users in the adjacent lane, e.g. with overtaking or oncoming vehicles. New features:

  • reaction to road edges, e.g. a patch of turf
  • particularly intuitive steering intervention
  • adjustment of sensitivity via a menu (early, medium, late)
  • the danger warning is reinforced by the active ambient lighting and the augmented reality head-up display

Active Lane Changing Assist

Active Lane Changing Assist cooperatively assists the driver of the new S-Class when moving to an adjacent lane. A lane-change to the right or left is only assisted if the sensors detect that the adjacent lane is separated from the present lane by an interrupted lane marking, and no other vehicles are recognised in the relevant danger zone. New features:

  • the longer search phase (15 s instead of 10 s, depending on country) in which the lane-change can take place, and
  • higher lateral dynamics (depending on country)

Active Emergency Stop Assist

Active Emergency Stop Assist brakes the vehicle to a standstill in its own lane if it recognises that the driver is no longer responding to the traffic situation for a longer period. In the new S-Class this still works if Active Distance Assist DISTRONIC with Steering Assist is not switched on. Other new features:

  • belt tensioning and braking impulse as a final signal of impending braking action
  • optional single lane change (at 80 km/h, no obstacles in adjacent lane)


This system included as standard is able to recognise typical signs of drowsiness and driver inattention, and displays a warning message prompting him/her to take a break. The additional microsleep warning is a new feature. This is based on monitoring of the driver's eyelid movements by a camera in the driver display (only in conjunction with certain optional equipment). The microsleep warning function is already active from a speed of 20 km/h.

Active Brake Assist with cross-traffic function

Active Brake Assist uses the onboard sensors to register whether there is a risk of collision with vehicles travelling ahead, crossing or oncoming. The system can give the driver a visual and acoustic warning if a collision appears imminent. If the driver's braking response is too weak, the system can also assist by increasing the brake pressure as the situation demands, and also initiate autonomous emergency braking if the driver fails to respond. New features:

  • the cornering function (e.g. crossing pedestrians when turning off)
  • extension of the cross-traffic function to long-distance routes (up to 120 km/h instead of 72 km/h)
  • warning and braking if there is oncoming traffic

Active Blind Spot Assist and exit warning function

Active Blind Spot Assist can give a visual warning - and if the indicators are operated also an audible warning - of potential lateral collisions in a speed range from around 10 to 200 km/h. If the driver ignores the warnings and still initiates a lane-change, the system can take corrective action by one-sided braking intervention at the last moment if the speed exceeds 30 km/h. When the vehicle is stationary, the exit warning function can warn against exiting because a vehicle (also bicycles) is passing within the critical area. This function is available when the vehicle is stationary and for up to 3 minutes after the ignition has been switched off. New features:

  • reinforcement of the warning by the active ambient lighting (also the exit warning)
  • thanks to the cameras of MBUX Interior Assist, a danger warning can already be given if the driver or front passenger merely move a hand towards the door handle.

Evasive Steering Assist

Evasive Steering Assist can assist the driver when seeking to avoid another road user recognised by the system in a critical situation. In the new S-Class, the system not only recognises stationary and crossing pedestrians, but also pedestrians and vehicles, including cyclists, travelling longitudinally. The speed range has been increased to 108 km/h (instead of 72 km/h), and assistance is also given on long-distance routes.

PRE-SAFE® Impulse Side

Together with the familiar PRE-SAFE® protection concepts for frontal and rear collisions, PRE-SAFE® Impulse Side forms a kind of virtual crumple zone that extends all around the vehicle.

As only a limited crumple zone is available in the case of a side impact, and even before the crash, PRE-SAFE® Impulse Side can move the affected driver or front passenger away from the acute danger zone as soon as the system detects that a side collision is immediately imminent. For this purpose, air chambers in the side bolsters of the front seat backrest are inflated in fractions of a second. In addition, when a side impact with another vehicle threatens, the vehicle body can be raised by the E-ACTIVE BODY CONTROL suspension (optional) within a few tenths of a second. This directs the impact forces towards particularly resistant structures in the lower area of the vehicle