Safety: At the highest level

Jul 6, 2016

Innovative Mercedes-Benz driving assistance systems are available in the new GLC Coupé, and within the framework of the Intelligent Drive Concept they fuse different sensor technologies, considerably increasing comfort and safety. COLLISION PREVENTION ASSIST PLUS, Crosswind Assist, Headlamp Assist and ATTENTION ASSIST are on board as standard. The Driving Assistance package Plus provides an even more comprehensive range of active safety features, comprising DISTRONIC PLUS with Steering Assist and Stop&Go Pilot, PRE-SAFE® Brake with pedestrian detection, BAS PLUS with Cross-Traffic Assist, Active Blind Spot Assist, Active Lane Keeping Assist and PRE-SAFE® The extensive range of assistance and safety systems is unique in the segment.

The basis for the numerous functions of the assistance systems is an extensive sensor system that provides the vehicle with a 360-degree view. This includes the stereo camera behind the windscreen in the area of the interior mirror and thus at the driver's eye level. Two camera eyes provide the stereo camera with a three-dimensional view of the area of up to 50 metres in front of the car, and it is able to monitor the overall situation ahead for a range of up to 500 metres and thus determine the position and movement of objects, especially of vehicles and pedestrians.

Two short-range radar sensors in the front bumper and at the side of the rear bumper respectively (range up to 30 metres), a long-range radar (up to 200 metres) including mid-range scan (up to 60 metres) behind the radiator grille and a multi-mode radar (up to 80 metres) in the centre of the rear bumper complete the sensor system.

The data from the camera and radar is compiled in a control unit in order to provide relevant data for a host of assistance systems – a process dubbed "sensor fusion" by safety experts. Intelligent algorithms analyse this data in order to detect and pinpoint the position of vehicles ahead, crossing, approaching from the rear and even from the front, as well as the position of pedestrians, within a large field of vision. In addition, the camera also detects road markings and a variety of traffic signs. The aim is all-round protection not just for occupants of the vehicle itself, but for other road users too.

The new GLC Coupé is fitted as standard with ATTENTION ASSIST, which warns the driver of inattentiveness and drowsiness. The COMAND system navigation function on motorways flags nearby break options as stopovers, providing the system has been specified in the vehicle. The ATTENTION ASSIST function offers an adjustable level of sensitivity and informs drivers in a separate view in the instrument cluster about their level of drowsiness and how long they have been driving since their last break.

COLLISION PREVENTION ASSIST PLUS: Autonomous braking when a rear-end collision threatens

Also part of the on-board standard equipment is COLLISION PREVENTION ASSIST PLUS with extended capabilities. The further enhanced system can provide even more effective aid in mitigating the severity of rear-end collisions or even in preventing them entirely.

To this end, the radar-based system constantly monitors the area of traffic in front of the vehicle, and can determine the distance and speed of the vehicles ahead. If the distance drops significantly below the safety threshold, the system issues a visual warning to the driver. If it detects a serious risk of collision, the driver receives an additional audible warning. At the same time, the system computes the braking power required to prevent the impact in the ideal case at speeds from as low as 7 km/h. If the warned driver then depresses the brake pedal firmly, the system is capable of boosting insufficient braking commensurate to the situation. In so doing, it makes the best possible use of the remaining distance in order to leave the vehicles behind room to brake.

If the driver fails to react, the new COLLISION PREVENTION ASSIST PLUS can go one step further and autonomously brake for slower or stopping vehicles. The system even brakes when stationary vehicles are detected up to a speed of 70 km/h, and can prevent rear-end collisions up to 40 km/h depending on the situation.

More comfort thanks to linear and lateral guidance: DISTRONIC PLUS with Stop&Go Pilot

DISTRONIC PLUS proximity control helps the driver to keep the vehicle at the desired distance from another vehicle in front that is travelling slower than the selected cruising speed. This basic radar-based function has now been enhanced by the addition of Steering Assist, which helps the driver with lateral guidance. The system helps the driver to keep the vehicle in the middle of its lane by generating a steering torque when driving in a straight line or even on slight bends.

The stereo camera recognises lane markings as well as vehicles driving ahead together with their spatial positioning, and relays this information to the electric steering assistance system. When driving at slow speeds, e.g. in congested traffic, Steering Assist can use the vehicle ahead as a means of orientation, enabling semi-autonomous following of tailbacked traffic even when there are no clear lane markings visible. The system can therefore increase ride comfort and considerably reduce driver stress in many traffic situations. DISTRONIC PLUS can be activated in a speed range between 0 and 200 km/h with a selector lever on the steering wheel. The desired speed can be set between 30 km/h and 200 km/h.

Drivers must keep their hands on the steering wheel at all times even when Steering Assist is activated, as the function only works in bends above a certain, speed-dependent radius. Legal considerations also mean there are no plans to introduce hands-free driving. The system's design is so refined that the sensors can detect whether the driver's hands are on the steering wheel. If they are not, the system first gives the driver a visual warning. If the driver fails to react, the system gives an audible warning and lateral guidance is deactivated. Linear control remains unaffected by this and continues to be available. Needless to say, the driver is able to override Steering Assist at any time. If the driver signals to change lane, for instance, the lateral guidance function will switch into passive mode for the duration of the lane change.

The performance capabilities of the basic DISTRONIC PLUS function have been increased once again. Now the system is able to brake at a rate of up to 5 m/s² without any intervention from the driver. There is faster acceleration if the "SPORT" modes are activated. Vehicle acceleration is also far more dynamic if the driver signals to overtake by switching on the indicators, assuming the adjacent lane is clear.

By combining the radar and camera data, DISTRONIC PLUS is also able to detect vehicles cutting in and vehicles ahead in adjacent lanes and take any necessary action promptly. This can prevent illegal overtaking on the inside lane on motorways and similar multi-lane highways, for example, by adapting the speed to that of vehicles in the outside lanes. Below 85 km/h moderate overtaking with a maximum relative speed of 20 km/h is still possible.

More safety on junctions: BAS PLUS with Cross-Traffic Assist

Apart from material damage, accidents at junctions often result in serious injuries. The new Brake Assist BAS PLUS with Cross-Traffic Assist from Mercedes-Benz is therefore not only capable of helping the driver prevent or mitigate the severity of rear-end collision in linear traffic. The Cross-Traffic Assist function can also help in the event of impending collisions with crossing traffic.

If this anticipatory system detects a hazardous situation of this type, it prompts the driver to start emergency braking by issuing visual and acoustic warnings. If the driver presses the brake pedal too tentatively, BAS PLUS will step in by automatically boosting brake pressure for effective emergency braking, even applying the brakes at full power if necessary. Applying just the right amount of braking power for the situation at hand maximises the available braking distance for traffic behind. The Cross-Traffic Assist function is effective at speeds up to around 72 km/h, while BAS PLUS is able to aid the driver in linear traffic at any speed.

For more safety in urban traffic: BAS PLUS and PRE-SAFE® Brake

The BAS PLUS and PRE-SAFE® Brake function include pedestrian detection. Thanks to the combination of stereo camera and radar sensors, it is now possible to detect pedestrians in front of the vehicle. Visual and acoustic warnings are triggered when a hazard is detected. If the driver reacts by braking, the braking power will be boosted by BAS PLUS with Cross-Traffic Assist as the situation requires, right up to full brake application. If the driver fails to react, the PRE-SAFE® Brake brakes the vehicle autonomously. PRE-SAFE® Brake with pedestrian detection is active up to approx. 72 km/h and can autonomously prevent collisions with pedestrians when travelling at up to 50 km/h.

Preventive protection when a rear-end collision threatens: PRE-SAFE® PLUS

PRE-SAFE®PLUS offers an extension of the familiar occupant protection measures in situations where following traffic poses a danger. A radar sensor in the rear bumper monitors the traffic following behind the car. If the risk of an impact from the rear is detected, the rear hazard warning lights are activated to alert the driver of the vehicle behind (not on vehicles with USA/Canada coding). In addition, the PRE-SAFE® preventive occupant protection measures, for example the reversible belt tensioners, are deployed. If the vehicle is stationary and the driver signals that they wish it to remain so (e.g. by applying the brakes, activating the HOLD function or engaging "P" using the selector lever), PRE-SAFE®PLUS comes to the driver's aid by increasing the brake pressure. The vehicle's brakes are "locked".

Keeping the vehicle firmly braked greatly reduces the strain placed on the occupants, such as the risk of whiplash injuries. It also serves as protection for other road users: uncontrolled vehicle movements after the initial impact that could lead to secondary collisions are reduced. These could be running into a vehicle in front or colliding with pedestrians or other road users at junctions, for example.

Responds to solid and broken lines on the road:

Active Lane Keeping Assist

The Active Lane Keeping Assist is now also able to intervene should the driver inadvertently cross a broken line when the neighbouring lane is not clear, meaning that a lane change could result in the risk of a collision. The system can determine if this is the case using the information from the stereo camera and the radar system. The latter has been supplemented by a sensor at the rear, which works in unison with the other sensors in the front and rear bumper.    

Active Lane Keeping Assist is not only capable of recognising critical situations such as overtaking vehicles, vehicles to be overtaken and parallel traffic, it can also respond effectively to oncoming traffic. When the adjacent lane is occupied, the system not only warns the driver with pulsing steering wheel vibrations when crossing the lane markings, but also intervenes with one-sided, course-correcting braking action induced by ESP®. It thereby optimally complements Active Blind Spot Assist and also enables collisions with oncoming traffic, which can often have far-reaching consequences, to be avoided.

Active Lane Keeping Assist is active at speeds between 60 and 200 km/h. If driver activity in the form of active steering, braking or acceleration, for example, is detected or when the indicators are switched on, both the warning and the corrective brake actuation are suppressed.

Warning of no-overtaking and no-entry signs: Extended Traffic Sign Assist

The Traffic Sign Assist which builds on the capabilities of the previous Speed Limit Assist represents yet another major contribution to accident prevention from Mercedes-Benz. The system even detects no-overtaking signs and can warn the driver if it detects no-entry signs. The camera on the inside of the windscreen continues to pick up speed limit signs, including those on overhead gantries and in roadworks, for example. The camera's data is cross-referenced against the information in the navigation system and can be displayed both in the instrument cluster and on the map display. If the camera fails to spot any road signs showing a speed limit or a speed limit is lifted, the legal speed limits based on the navigation data are shown instead, such as a maximum speed of 100 km/h on country roads in Germany or 50 km/h in built-up areas.

No-overtaking zones and the signs ending such zones are also registered and displayed. In the case of signs imposing access restrictions, the system emits an acoustic warning together with a visual warning in the instrument cluster – making an effective contribution towards the prevention of serious accidents caused by wrong-way drivers.

Automatic parking manoeuvres: Active Parking Assist

Active Parking Assist enables automated parking with active steering and brake intervention in both parallel and perpendicular parking spaces. What is more, the system is now also able to manoeuvre out of parallel parking spaces again all by itself with automatic steering and brake control, assuming the vehicle was parked there automatically beforehand.

When travelling at speeds below 35 km/h, ultrasound sensors with an extended range in the bumpers' side sections survey the right side of the road for suitable parallel and end-on parking spaces. The same procedure is carried out for the left side of the road if the driver activates the left direction indicator. A symbol in the instrument cluster shows that the system is in the process of measuring. If a suitable parking space is identified, an arrow appears alongside the symbol indicating that the system is ready for automatic parking. All the driver now has to do to activate the system is engage reverse gear and confirm by pressing the OK button on the steering wheel.

Active Parking Assist steers and brakes the vehicle automatically and shows the necessary action that the driver needs to take in each case in the display, such as engaging the correct gear. The driver is able to control acceleration of the vehicle by lightly pressing the accelerator or releasing the brake.

Continuous high beam without dazzle: Adaptive Highbeam Assist Plus

Some 20 percent of all kilometres driven in Germany are driven at night. But 40 percent of all accidents happen during that time. One of the main reasons for this is reduced visibility.

For the first time, Adaptive Highbeam Assist Plus allows the high-beam headlamps to be kept on permanently while driving by masking out any other road user detected in the beams' cone of light. If the camera-based system registers either oncoming traffic or vehicles ahead, it will adapt the light distribution according to the traffic situation when high beam is switched on. Consequently, the driver can leave the high-beam headlamps on at all times and use their full range without irritating or even endangering other road users. There is no need to switch them on and off manually, resulting in a significant increase in the overall driving time with high beam.

Adaptive Highbeam Assist Plus likewise makes use of the stereo camera also employed by other assistance systems. If its image recognition algorithm picks up a vehicle that is oncoming or driving ahead, it actuates a mechanism in the headlamp module. This then masks the section of the LED headlamps' high-beam cone of light where there are other vehicles to prevent their drivers from being dazzled. If road users are detected outside the area that can be masked – for instance when cornering with multiple vehicles in the headlamps' beams – the system will switch to the familiar function of headlamp range control using the low-beam headlamps.

Possible backglare caused by increased use of the main beam and highly reflective signs at the side of the road are also detected and eliminated by dimming the headlamps accordingly.

All-round visibility in the GLC Coupé

In addition to Active Parking Assist, simpler handling and a clearer view, for instance when manoeuvring in tight spaces or driving in dense urban traffic, are ensured by the 360° camera, which is able to show the vehicle and its surroundings from different perspectives. Functions of the 360° camera in detail:

  • The virtual bird's-eye view shows an aerial view of the GLC Coupé and the surrounding area three metres to the front and rear and 2.5 metres to the sides of the vehicle. 
  • Display of perspectives which are not actually physically possible. E.g.: when manoeuvring in a multi-storey car park with a low ceiling a bird's-eye view of the car and its surroundings are shown from a height of over three metres, although the ceiling is actually only a few centimetres above the vehicle. 
  • Visualisation of the sides of the vehicle and its surroundings to avoid knocks to the exterior mirrors or the wheel rims, for example.
  • Visualisation of obstacles below the vehicle's beltline, which are not visible to the driver.
  • Visualisation of crossing traffic in front of and behind the vehicle when manoeuvring out of tight parking spaces or in tight exits.
  • Visualisation of pedestrians on the pavement when manoeuvring out of tight parking spaces or in tight exits.
  • The colour of the car on the COMAND display always corresponds to the vehicle's actual paintwork.

Relaxed driving experience

The improved ergonomics and simpler controls in the GLC Coupé compared to its predecessor model also help to enhance safety. All important vehicle functions and settings can be carried out intuitively using the central rotary pushbutton or the touchpad. The desired settings or information are clearly visualised by the large, partially integrated colour media display in the middle of the dashboard. Direct selection buttons next to the light switch module to the left of the steering wheel additionally enable direct activation of the most important assistance systems.

Also new is the Head-up Display. It shows important information on the front windscreen, directly in the driver's field of vision, thus providing for clear legibility and for less distraction from the road ahead. The system provides information on speed, posted speed limits, navigation instructions and messages from the DISTRONIC system.

Hybrid body: the safe foundation

In keeping with the Mercedes-Benz tradition, the body forms the foundation for exemplary occupant protection in the event of a crash. A high-strength safety passenger compartment forms the core of this concept. It is surrounded by specifically designed and crash-tested deformation zones, which ensure the best possible safety for the occupants by virtue of optimised force paths and a combination of die-cast aluminium components and ultra-high-strength materials. This assures the new GLC Coupé of the potential to put in an excellent showing in all the worldwide rankings.

The measures in detail:

  • Highly robust passenger compartment consisting of high-strength and ultra-high-strength sheet steel, tailored blanks (sheet steel with graduated wall thicknesses) and cast aluminium components
  • Bodyshell structure, the front and rear of which can absorb energy with purposeful deformations 
  • Large deformation zone of the front due to a subframe that absorbs additional energy in an accident
  • Several parallel load paths for improved load distribution in partial frontal collision (offset crash)
  • Additional strut made of high-strength steel between the damper dome and windscreen cross member on the driver's side which distributes the load from forces in the upper side member plane and reduces steering and pedal intrusion in the footwell.
  • Additional firewall supports between the front and outer longitudinal members, which prevent the front wheel from intruding into the footwell in a severe, offset frontal collision 
  • Pressure-die-cast magnesium cockpit cross member between the A-pillars
  • Doors with reinforcement profile
  • Main floor with massive tunnel reinforcement and continuous floor side members
  • Rear seat cross member with additional reinforcements, separated from the rear floor
  • Composite rear structure with longitudinal floor members in graduated plate thicknesses and a corresponding rear centre section

On the GLC 350 e 4MATIC Coupé with plug-in hybrid technology, a lithium-ion battery and other high-voltage components are integrated in the rear area. Special cast aluminium parts form a deformation-proof area to shield off these components.

Airbags & co.: cushioning protection for the occupants

Three-point seat belts with pyrotechnical belt tensioners and belt force limiters are installed for driver, front passenger and passengers on the outer rear seats. The centre seat of the second row is equipped with a standard 3-point belt system. A rear seat-belt status display in the instrument cluster informs the driver whether the passengers in the back have fastened their seat belts. i-Size child seat anchorage points on the outer rear seats ensure safe attachment of appropriate child seats with additional anchorage points at the top of the rear seat backrest. The front passenger seat can be fitted with automatic child seat recognition, which dispenses with the existing transponder and instead works with a weight mat. This enables any standard child seat to be used. The airbag is automatically deactivated in this case and reactivated once the child seat has been removed.

In addition, a host of airbags provides occupant protection in an accident. These include:

  • a windowbag in the roof area between A-, B- and C-pillars for the head area of driver, front passenger and passengers in the outer rear seats 
  • Combined thorax/pelvis sidebags for driver and front passenger, which are able to provide additional protection in the event of a side impact. Sidebags for the outer rear seats are optionally available. 
  • Kneebag for the driver to protect the knees and stabilise the upper body, which positively influences occupant movement in an accident.
  • Adaptive airbags for driver and front passenger with two-stage staggered deployment, depending on the detected severity of the impact and seat position.

The GLC Coupé is equipped with Mercedes-Benz emergency call eCall. An emergency call can be made automatically or manually. It is triggered automatically after deployment of one of the pyrotechnic belt tensioners or airbags in the vehicle. The service centre then establishes voice communication with the vehicle.

Best possible protection for more vulnerable road users

Mercedes-Benz attaches priority to the protection of more vulnerable road users, such as pedestrians or cyclists. The GLC is equipped with an active bonnet which is raised by around 80 millimetres in certain accident scenarios to provide additional deformation space. Under the bonnet, the package has been further optimised with an engine cover and deformable air intake, creating yet more deformation space. These measures ensure that the GLC Coupé meets the markedly more stringent Phase 3 requirements of Euro NCAP pedestrian protection.

BAS PLUS warns when pedestrians are detected in the danger zone by the stereo multi-purpose camera. The PRE-SAFE® Brake with pedestrian protection triggers autonomous braking when the system detects a pedestrian in the danger zone and the driver does not react to the system's warnings. This pedestrian detection, in conjunction with the optionally available Driver Assistance package Plus, represents a milestone in preventing accidents with pedestrians and/or reducing their consequences.

Euro NCAP's "Best in class" award for the GLC shows just how effective this concept is. The coupé version clearly has the potential to receive this rating too.