Mercedes-Benz has launched the new tenth-generation E-Class, introduced at the North American International Auto Show (NAIAS) this January. (Earlier post.) The new generation features technology innovations in a number of areas, including driver assistance and powertrains, with new efficient engines and a plug-in hybrid version.
Initially, the E 200 d models of the new E-Class will be available with an all-new four-cylinder OM 654 diesel engine (earlier post), while the E 200 will be powered by a four-cylinder gasoline engine and the E 350 d by a six-cylinder diesel.
|Mercedes-Benz E-Class, E 220 d. Click to enlarge.
Further model variants will later be added to the range, including the E 350 e plug-in hybrid with round 30 km (18.6 miles) of all-electric range. Its four-cylinder gasoline engine, in conjunction with the electric motor, gives it a total system output of 210 kW (286 hp) with a system torque of 550 N·m.
Also to come will be the E 300 rated at 180 kW (245 hp) with a torque of 370 N·m as well as the E 400 4MATIC, with a six-cylinder gasoline engine delivering 245 kW (333 hp) with a torque of 480 N·m.
Further variants will later complete the engine range, including the new four-cylinder diesel unit developing 110 kW (150 hp). The range of gasoline engines will comprise four-cylinder versions with outputs ranging from 135 to 180 kW (183 to 245 hp) plus a six-cylinder variant developing 245 kW (333 hp).
All engines for the new E-Class are equipped with the ECO start/stop function. The gasoline engines meet the requirements of the EU 6 emissions standard, while the new OM 654 four-cylinder diesel engine is already configured with future RDE limits in mind.E 350 e PHEV. E 350 e accelerates from 0 to 100 km/h in 6.2 seconds, and offers fuel consumption of 2.1 liters per 100 kilometres (112 mpg US) corresponding to 49 grams of CO2 per km. All-electric driving is supported to a top speed of up to 130 km/h (81 mph).
The E 350 e comes as standard with AIR BODY CONTROL air suspension as well as pre-entry climate control that can be controlled from a smartphone app.
The 6.2 kWh lithium-ion battery can be charged from an external power source. Thanks to an on-board charging system, this takes around one and a half hours at a wallbox. A charging time of around three hours is achievable via a standard domestic socket.
Working in the background, intelligent engine management selects the ideal combination of combustion engine and electric motor automatically. If desired, the driver can regulate the hybrid interplay and driving characteristics with the help of four operating modes (HYBRID, E-MODE, E-SAVE and CHARGE) and five transmission modes, which emphasize economy, comfort or sportiness, for example.
If a destination is programmed into the navigation system, an intelligent operating strategy controls charge and discharge of the high-voltage battery to ensure optimal use of energy over the entire route. Another aim of this route-based operating strategy is to reach urban areas with a fully charged battery if possible, so that the vehicle can be driven efficiently in stop-and-go traffic—and frequently in electric mode.
The haptic accelerator pedal facilitates economical driving. When the driver feels a resistance point, he or she knows that maximum electric performance is being delivered and that the combustion engine will kick in if they depress the accelerator pedal further. A double impulse prompts the driver to take their foot off the accelerator pedal—say, for independent deceleration through the generator effect of the electric motor if the distance warning system provided as standard detects a slower-moving vehicle in front. This recovers energy and avoids frequent braking, particularly in stop-and-go traffic.
New OM 654 four-cylinder diesel. The new four-cylinder diesel unit marks the birth of a new Mercedes-Benz engine family. Despite having a lower displacement than its predecessor, reduced to just under two litres, and weighing around 16% less, the new diesel powerplant has an output of 143 kW/ 194 hp—18 kW more than the previous engine. When installed in the E 220 d, the engine delivers an NEDC combined consumption of 3.9 liters per 100 kilometres (60 mpg US), which equates to CO2 emissions of 102 grams per kilometer. The engine is also more compact than its predecessor.
The lower weight and extra output give more agility and enhanced driving pleasure; its compact dimensions mean that the engine can be used in a range of different powertrain configurations, as well as for all-wheel-drive and hybrid vehicles.
The engine is also already designed to meet future legislation on emissions (RDE – Real Driving Emissions). In future, exhaust gas aftertreatment systems will not only have to meet the prescribed emission limits on the test stand, but also under a wide range of real-life conditions. The WLTP cycle (Worldwide harmonized Light vehicles Test Procedure), which is scheduled to supersede the NEDC measuring cycle in future, was another focus of attention during the development phase.
The design of Mercedes-Benz’s new diesel engine offers potential for further development in terms of both output range and integration of further technology modules, for example in order to take advantage of the opportunities presented by further advances in electronics.
6-cylinder diesel engine. The E-Class carries over from the previous model series the 6-cylinder diesel engine with 190 kW output and 620 N·m torque. However, the charge-air cooling has been changed to an air/water system. This contributes to increased agility.
Gasoline engines. The BlueDIRECT four-cylinder gasoline engines in the E-Class use third-generation direct injection with spray-guided combustion. The system pressure is up to 200 bar, the pressure being variably optimized according to the engine’s mapping. Piezo injectors enable optimal mixture formation with up to five injections per power stroke.
The third-generation direct injection is supplemented by rapid multi-spark ignition (MSI). The MSI system enables up to four sparks to be discharged in succession within one millisecond, creating a plasma with a larger spatial expansion than conventional ignition.
The rapid multi-spark ignition can be controlled to vary both the timing of the sparks and the combustion period to suit the relevant operating point. This provides scope for optimizing the center of combustion and improved residual gas compatibility. This in turn reduces fuel consumption. The result of this is excellent utilization of the fuel with minimum emissions.
Nine-speed automatic. In addition to a 6-speed manual transmission for the four-cylinder gasoline engines, Mercedes-Benz offers the new 9G-TRONIC nine-speed automatic transmission as standard for all E-Class models. Its broad ratio spread (9.15) for gears one to nine allows an overall reduction in engine speed—a key factor behind the high level of energy efficiency and ride comfort.
Shortened shift and response times ensure optimum immediacy combined with outstanding ease of shifting. This is linked to the transmission’s high efficiency, which is an advantage in terms of fuel consumption.
4MATIC all-wheel drive. For the first time, the E 200, too, will be available with 4MATIC permanent all-wheel drive. It improves traction and driving stability, especially under difficult road conditions. The combination of the ESP driving dynamics control system with the 4ETS electronic traction system makes regular differential locks superfluous. This saves weight and noticeably improves handling safety as well as ride comfort.
Assistance systems. The new Mercedes-Benz E-Class is the first series production vehicle to be awarded a test licence for autonomous driving in the US state of Nevada. This simply requires some software modifications while the standard hardware otherwise remains unchanged.
Specifically, for testing purposes, it is necessary merely to make some minor software modifications to the DRIVE PILOT control unit—the “Intelligent Drive Controller”. More specifically, changes were made only to Steering Pilot and Speed Limit Pilot. For example, Hands-On Detection was shut down and the steering dynamics were significantly increased.
Mercedes’ Integral Safety and Intelligent Drive are becoming increasingly intertwined, working in synergy in a cross-system concept. Its components can:
- assist and provide stress relief during normal driving;
- detect dangers;
- warn, assist and, if necessary, intervene in a timely manner; /li>
- consequently prevent accidents or reduce the severity of accidents; and
- activate protective measures such as the PRE-SAFE components as a precaution in the event of danger and thus provide on-demand protection.
The individual functions are linked to networked sensors including an enhanced multi-purpose stereo camera behind the windscreen and new multi-stage radar sensors with adjustable range and opening angle around the vehicle plus tried-and-tested sensors such as ultrasonic sensors and the 360° camera.
The combined use of data from the sensors allows analysis of complex traffic situations, better detection of potential dangers on the road and, therefore, the ability to further enhance the capabilities of the safety and assistance systems.
To be able to offer optimal assistance also in wintry conditions, the latest-generation front radar is provided with Radom heating, which effectively prevents the sensor being interfered with by snow.
The new E-Class comes as standard with Active Brake Assist. This further advanced system can provide effective aid in mitigating the severity of rear-end collisions or even in preventing them entirely. 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 following distance drops significantly below the safety threshold at speeds above 30 km/h (18.6 mph), the system gives the driver a visual warning.
If, in the speed range between 7 and 250 km/h (4.4 and 155 mph), it detects an acute risk of collision because of slower or stopped vehicles or, in the speed range between 7 and 80 km/h (50 mph), because of stationary vehicles or crossing pedestrians, the system gives the driver an additional audible warning. It also computes the brake pressure required to prevent a collision, if this is still possible.
If, having been warned, the driver then steps on the brake pedal, the system is capable of boosting insufficient braking pressure in line with the needs of 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 respond, Active Brake Assist can go one step further and, if the danger of collision persists, can perform autonomous braking for slower moving and stopping vehicles at speeds of up to 200 km/h (124 mph) to mitigate the severity of the accident and ideally prevent the collision entirely.
The system also brakes if stationary vehicles or crossing pedestrians are detected up to a speed of around 60 km/h (37 mph), and can prevent collisions up to 50 km/h (31 mph), depending on the situation.
ATTENTION ASSIST with adjustable sensitivity, which can warn the driver in timely manner of inattentiveness and drowsiness, is also included as standard. Crosswind Assist helps the driver by enabling them to clearly counteract disturbances such as strong gusts of wind by means of one-sided braking via ESP.
DRIVE PILOT The E-Class optionally offers additional assistance systems, the key innovations of which have been combined in a new Driving Assistance package. The most important functions include semi-autonomous driving on motorways, country roads and even in the city as well as assistance when changing lanes on multi-lane roads—e.g., when overtaking. Furthermore, it is capable in more and more situations of autonomously braking the vehicle if required and providing active assistance during evasive maneuvers.
The centerpiece of the Driving Assistance package is DRIVE PILOT. This assistance system, as Distance Pilot DISTRONIC, automatically maintains the correct distance to vehicles in front by adjusting the car’s higher desired speed to that of a slower-moving vehicle ahead before accelerating back up to the desired speed once the way ahead is clear again.
With its Steering Pilot subfunction, it can also keep the E-Class in lane up to speeds of 210 km/h (130 mph). The driver no longer needs to operate the brake or accelerator pedal during normal driving and also receives plenty of steering assistance.
For orientation, DRIVE PILOT uses an enhanced multi-purpose stereo camera behind the windscreen and new radar sensors beneath the radiator grille and the rear bumper to detect road markings, the vehicle in front and also its surroundings. Consequently, at speeds up to 130 km/h, it is not dependent on clearly visible lane markings as it can continue to intervene actively, like in a swarm, if the lines on the road are unclear, e.g. at roadworks, or even if there are no lines on the road at all.
If COMAND Online is fitted, DRIVE PILOT can provide enhanced comfort through the selectable Speed Limit Pilot subfunction. By means of Distance Pilot DISTRONIC, it can autonomously adjust the vehicle’s speed in response to camera-detected speed limits, including gantries and signs at roadworks, or speed limits logged in the navigation system, such as 50 km/h in built-up areas or 100 km/h on country roads.
Despite active longitudinal and transverse guidance with enhanced steering assistance, DRIVE PILOT continues to be designed as a semi-automated assistance system in which the driver still needs to keep their hands on the steering wheel. On the one hand, this is a technical necessity, while, on the other, it is a legal requirement. Intelligent hands-on detection provides a noticeably increased customer benefit while taking account of, for example, vehicle speed or road type and curvature.
Active Emergency Stop Assist can brake the vehicle to a standstill in its lane if it detects that the driver is permanently not taking control while on the move. If there is no steering wheel movement over a longer period when the Steering Pilot is active, the system gives the driver a visual and audible prompt to place his/her hands on the wheel. If, after being repeatedly warned, the driver does not react by steering, accelerating, braking or pressing a Touch Control button, the vehicle safely decelerates to a standstill in its lane and warns the traffic behind using the hazard warning flashers.
An Active Lane-change Assistant assists the driver when changing lanes. Once the driver has indicated to turn for at least two seconds, the Active Lane-change Assistant helps with steering the vehicle into the desired adjacent lane if it detects that the lane is unoccupied. The driver merely monitors the change of lane. It is irrelevant whether the driver wants to move to the right-hand lane or change to the left lane for overtaking.
The criteria for operation of Active Lane Change Assist are:
- operation of the turn indicator for longer than two seconds;
- the unoccupied zone detection system allows a lane change within three seconds;
- Steering Pilot is activated; and
- the vehicle is traveling on a multi-lane, motorway-like road, detected via the navigation module integrated into COMAND Online; and
- speed is between 80 and 180 km/h (50 and 112 mph).
A long-range radar system and the stereo camera monitor the area in front of the vehicle, while multi-mode radar sensors permanently check the area to the rear and sides.
Active lane change is aborted by the system if the sensor system detects an obstacle, no longer sees lane markings, the driver countersteers or Steering Pilot is switched off.
The intelligent innovations of the Driving Assistance package include Evasive Steering Assist. This can help the driver to avoid a pedestrian detected by the assistance system using the radar sensors and multi-purpose stereo camera. If the driver initiates an evasive maneuver by turning the steering wheel, the system provides assistance by adding precisely calculated steering torque to support the movement of the steering wheel.
This torque helps the driver to avoid the pedestrian in a controlled manner and then makes it easier to straighten the vehicle up again so that it can drive past safely. While the philosophy behind Evasive Steering Assist is to provide the driver with significant assistance, the initiative to take evasive action must come from the driver. This is because, if evasive action were automatic, a previously inattentive driver might be so surprised by the spontaneous movement of the steering wheel that they might react incorrectly and, for example, attempt intuitively to steer in the opposite direction.