Heavy traffic on busy roads is in itself very unsafe and in which case the seconds count. Specifically, these seconds determine the end of someone's life. While driving on the track, the driver must be measured and attentive, moreover, under no circumstances should he be distracted by trifles. The driver can always think and get distracted from the road, and this leads to an inevitable collision, the Pre-Safe system is designed to prevent or minimize harm from a possible collision.
When this system was tested on car stimulators, 70 ordinary invited German drivers were offered to accelerate to 80 km on an ordinary suburban road and just drive. After the driver more or less adapted to this driving style, in order to distract him from the road, he was shown that there was a disaster on the road on the side of his car: cars with policemen, a certain number of people on the side of the road - all this distracted the attention of the majority. The test drivers were so distracted that they did not react to any of the signs given by the car equipped with the Pre-Safe system ended up working. critical braking, which reduces the speed by 10 km, but still, with all this, the force of a probable collision is miniaturized by 40%.
This system uses radar technology in order to recognize danger on the road and alert the driver about it. Specifically, these radar technologies have passed unprecedented tests (cars equipped with the Pre-Safe system drove about 1 million km on ordinary roads before entering serial production). This system was also tested on car simulators and test sites. It's not a secret for anyone that accident prevention is one of the priority tasks for any self-respecting auto giant, so the Mercedes-Benz company is far from being the first in this case.
The Pre-Safe system is designed to save the life of the driver and not only him, it was developed by Mercedes-Benz. A car equipped with such a system lets the driver know visually and audibly about a critical approach to another car and the possibility of a collision, if the driver does not react to this, then the car itself is in automatic mode includes partial braking (in the amount of 40%, the vehicle's braking force is applied 2.6 seconds before the expected collision).
This system scans all movement within the radius of the car, it gives the driver several chances to react correctly and change the situation by braking just right. With all this, the seat belts are tightened on the driver and the passenger who sits next to each other, and airbags are inflated in the multi-profile seats, while the position of the body of passengers and the driver is fixed, everything is made so that the body of the driver and passenger takes the most harmless position, which minimizes damage during a probable accident.
Just a little more than 1 second before the collision, the car equipped with such a system begins to brake automatically, while the speed of the car that is moving towards the collision is not very significant, but still decreases, and this in turn minimizes the force of the impact.
If the driver reacted to the remarks of the car, then the latter, with the help of a certain system, helps him to brake, while the braking force increases. It should be noted that before the introduction of this system, Mercedes-Benz cars were massively equipped with other safety systems, which, with the assistance of Pre-Safe, increased the safety of the car itself.
The Pre-Safe system in combination with other systems from Mercedes-Benz significantly minimizes harm during an accident or helps to prevent it. Usually 70% of drivers react to those signs, which are given by a car equipped with the Pre-Safe system, but the other 30% do not react and a collision still becomes inevitable.
Heavy traffic on busy roads is in itself very dangerous and in which case the seconds count. It is these seconds that determine the outcome of someone's life. While driving on the highway, the driver must be calm and attentive, and in no case be distracted by trifles. The driver can always think and get distracted from the road, and this entails an inevitable collision, the Pre-Safe system is designed to prevent or minimize damage from a possible collision.
When this system was tested on car stimulators, 70 ordinary invited German drivers were offered to accelerate to 80 km on a regular country road and just drive. After the driver had more or less adapted to this driving style, in order to distract him from the road, he was shown that an accident had occurred on the side of his car: cars with police officers, a certain number of people on the side of the road - all this distracted the attention of the majority. The tested drivers were so distracted that they did not react to any signs given by the car equipped with the Pre-Safe system, as a result, it worked emergency braking, which reduces the speed by 10 km, but nevertheless, the force of a possible collision is reduced by 40%.
The system uses radar technology to detect threats on the road and alert the driver. It is these radar technologies that have passed unprecedented tests (cars equipped with the Pre-Safe system drove about 1 million kilometers on normal roads before entering mass production). This system was also tested on car simulators and test sites. It's no secret that accident prevention is one of the top priorities for any self-respecting auto giant, so Mercedes-Benz is far from being the first in this case.
The Pre-Safe system is designed to save the life of the driver and not only him, it was developed by Mercedes-Benz. A car equipped with such a system lets the driver know visually and by ear about a critical approach to another car and the possibility of a collision, if the driver does not react to this, then the car itself automatically turns on partial braking (40% of the braking force of the car is used 2.6 seconds before the expected collision).
This system scans all movement within the radius of the car, it gives the driver several chances in order to react correctly and change the situation by braking in time. At the same time, the seat belts are tightened for the driver and the passenger who is sitting next to each other, and airbags are inflated in multi-profile seats, while the position of the body of passengers and the driver is fixed, everything is done so that the body of the driver and passenger takes the safest position, which minimizes damage during time of possible accident.
Just a little more than 1 second before the collision, a car equipped with such a system begins to automatically brake, while the speed of the car that is moving towards the collision is not very significant, but still decreases, and this, in turn, minimizes the force of the impact.
If the driver reacted to the car's remarks, the latter, with the help of a certain system, helps him to brake, while the braking force increases. It is worth noting that before the introduction of this system, Mercedes-Benz cars were massively equipped with other safety systems that, when interacting with Pre-Safe, increased the safety of the car itself.
The Pre-Safe system in combination with other systems from Mercedes-Benz significantly minimizes damage during an accident or helps to prevent it. Usually 70% of drivers react to those signs that are given by a car equipped with the Pre-Safe system, but the remaining 30% do not react and a collision still becomes inevitable.
One of the latest safety innovations is the Pre-Safe system, offered by the German concern DaimlerChrysler. As the name suggests, it works to anticipate a collision.
To date, cars of the brand and are equipped with it. The vehicles are equipped with three remote sensors operating on the radar principle. Two of them, with a frequency of 24 GHz, are located in the front bumper and serve an area of up to 30 m with an angular sweep of up to 80 °. Another one operating at a frequency of 77 GHz is in the radiator grille. It "drills" the space in front of the car at a distance of 150 m with a 9 ° sweep.
The sensor readings are sent to the system control unit. When the distance to an obstacle - for example, the next car in front of you - is reduced to a dangerous value, dashboard the red warning light comes on. If the car in front of you suddenly starts to slow down, an additional beep will sound. At the same time, Pre-Safe calculates the pressure in brake system required to avoid collision. When you press the brake pedal, another electronic assistant is included in the process - Brake Assist PLUS (BAS PLUS). However, as practice shows, drivers do not immediately react to warning light and sound signals, even repeated many times. For those who are especially inattentive, the system provides for autonomous braking of the car with a deceleration rate of up to 0.4 d. 2.6 seconds before the calculated collision moment, determined by the control unit, a light and sound alarm is triggered, reminding of the possible. If the driver still does not react, after another second, Pre-Safe takes control of the situation and seriously intervenes in driving. Partial braking is performed. The system gives the driver one more second to understand the situation. If it does not brake sharply, Pre-Safe will take action to reduce the potential impact of a collision by 40%.
The system also includes security elements passive safety for Mercedes-Benz cars... Following the warning signals, the front seats automatically assume the optimal position for the deployment of the airbags. The open side windows and sunroof close to prevent passengers from falling out of the vehicle when sliding or tipping over, and to make the side curtain airbags work more efficiently. Pre-Safe operates in the speed range from 30 to 180 km / h on the motorway, where sensors are able to distinguish between individual vehicles, or up to 70 km / h in heavy city traffic.
General description of the system
The PRE-SAFE system (preventive passenger safety system) includes the following functions:
* Reversible seat belt pretensioner for driver and front passenger
* Setting the position of the front passenger seat
* Automatic closing of lifting / sliding sunroof (SHD).
The PRE-SAFE system is activated in critical traffic situations (forward movement), in a situation that could potentially result in an accident. The functions that are actually activated before the accident (see the list of functions above) must create optimal conditions before the anticipated collision.
The following control units and elements are active participants in the functioning of the system:
* Control unit for passenger restraint system ARCADE Airbag (N2 / 11)
* ESP control unit (N30 / 4)
* Reversible driver seat belt pretensioner (A76)
* Reversible front passenger seat belt pretensioner (A76 / 1)
System operation
Conditions for system operation
* Terminal 15 "ON"
* Vehicle speed v> 30 km / h and vehicle forward movement
Critical vehicle driving conditions in which the PRE-SAFE system is triggered:
* Emergency braking, in which the brake assistant (BAS) is activated
* Oversteer (Querdynamik) is determined by: steering wheel angle, skid angle, lateral acceleration, wheel speed
* Understeer (Querdynamik) is determined by: steering wheel angle, skid angle, lateral acceleration, wheel speed
Note:
* A critical state of vehicle movement is taken into account when driving forward and in reverse.
* Information " Reverse gear ON "is sent by the electronic gear selection module EWM (N15 / 5).
The PRE-SAFE actuation logic is integrated into both reversible belt tensioners (A76, A76 / 1), i.e. both reversible belt tensioners receive and transmit the same signals via the CAN-C data bus, which are necessary for the actuation and implementation of the PRE- system functions. SAFE. Depending on which situation is recognized by the PRE-SAFE system, emergency braking(Langsdynamik) or skidding (Querdynamik), the operating mode of the front left / front right reversible seat belt pretensioners is different (A76, A76 / 1).
Emergency braking (longitudinal dynamics)
The data transmitted by the ESP control unit (N30 / 4) instructs the reversible front left / front right seat belt pretensioners (A76, A76 / 1) to perform the corresponding PRE-SAFE functions:
1. Tensioning the seat belt
Prerequisites:
* Both driver- / front passenger seat belts are fastened
* The front passenger seat is recognized as occupied (CAN-C signal from ARCADE Airbag control unit (N2 / 11)).
2. Preparing the front passenger seat for possible movements
The following seat settings should be standardized:
Longitudinal installation and leveling
Backrest tilt
Front left / right reversible belt tensioners (A76, A76 / 1) cyclically send readiness information via the CAN-C data bus to the central ZGW interface (N93), and from there via the CAN-B data bus to the front seat control unit passenger with memory function (N32 / 2)
Only if the front passenger seat is not in the optimal position (for a collision) and is recognized as occupied (CAN-C signal from the ARCADE (N2 / 11) airbag control unit), the seat is adjusted to the optimum position according to the PRE-SAFE situation.
This automatic adjustment of the front passenger seat can be interrupted at any time by pressing the seat adjustment buttons.
The seat will not return to its original position after the PRE-SAFE system has ended.
When the PRE-SAFE system is triggered, the following settings are made in the seat position:
If the passengers are wearing (the seat belt buckle is fastened):
* If the angle of inclination of the backrest is more than 28 ° from the front end position, the backrest moves to the upright position. If the tilt angle is less than 28 °, no settings are made.
* The angle of the seat cushion in the front section is set to the middle position. If the front of the cushion is raised high, no change is made.
* If the seat is moved too far forward, then it moves 100 mm back from the full forward position. If, on the contrary, it is very strongly shifted back, then it moves forward 50 mm from the extreme rear position.
If the passengers are not fastened (the seat belt buckle is not fastened):
* If the angle of inclination of the backrest is more than 20 ° from the front end position, the backrest moves to the upright position. If the tilt angle is less than 20 °, no settings are made.
* The seat cushion at the front can be lifted up to the end position.
* The seat is lowered to the lowest position.
* If the seat is moved very far back, it moves forward 100 mm from the rearmost position. Note:
* Any settings and movements of the front passenger head restraint associated with the operation of the PRE-SAFE system are not provided.
* The operation of the PRE-SAFE system, namely its effect on the front passenger seat, can be disabled using Star-Diagnose in the settings of the front passenger seat control unit (N32 / 2).
* For the driver's seat, any settings and movements associated with the operation of the PRE-SAFE system are not provided.
Lateral vehicle acceleration (Querdynamik)
1. Seat belt tension: (see emergency braking)
2. Preparing the front passenger seat for possible movements: (see emergency braking)
3. Closing the tilt-slide sunroof (SHD): signals from the ESP control unit (N30 / 4) and the steering column module (N80) trigger the PRE-SAFE system, namely: reversible seat belt pretensioners (front left / front right (A76 , A76 / 1), tilt / slide sunroof (SHD) closes
The overhead control panel DBE (N70) automatically closes the tilt / slide sunroof (SHD) after receiving a "command" from the PRE-SAFE system via the CAN-B data bus via the central ZGW interface (N93). This function can be canceled at any moment by operating the tilt / slide sunroof control switch (N70s1). If the DBE control unit (N70) continues to receive information that the PRE-SAFE system has been triggered, the sunroof closing process is resumed. The return of the tilt-slide sunroof to its initial position after the completion of the PRE-SAFE system activation situation is not performed.
Note:
When the hatch is closed, the anti-pinch protection works. When an obstacle is detected, the sunroof drive switches to reverse movement... The PRE-SAFE system is not available for the optional sliding glass roof (on type W251).
Termination of the PRE-SAFE system
The reversible front left / front right seat belt pretensioners (A76, A76 / 1) set the control signal on the CAN-C data bus to a passive level if the PRE-SAFE situation is no longer recognized.
Correspondingly, if the front passenger seat adjustment is interrupted by the passenger seat control unit (N32 / 2), with memory, although the optimum position for the PRE-SAFE system has not yet been reached. If the vehicle accelerates below 0.3 g (negative acceleration), the reversible front left / front right seat belt pretensioners (A76, A76 / 1) loosen the additional tensioned seat belts of the driver and front passenger. If the first step of loosening the seat belts has not been completed successfully, a second attempt at loosening the seat belts is initiated. The automatic closing of the tilt-slide sunroof (SHD) is not interrupted at the end of the PRE-SAFE system.
The return of the front passenger seat and tilt / slide sunroof (SHD) to the home position after the PRE-SAFE situation is over is not performed.
The yellow warning light is on. signal lamp... Electric parking brake defective.Switch off the ignition.
Press and hold the electric parking brake knob for at least ten seconds. engage first gear. shift the transmission to position. Contact a qualified specialist workshop. Yellow warning light and red control lamp are burning. The electric parking brake is defective.
Release the electric parking brake manually. Or: Release the electric parking brake automatically.
If the parking brake is electric. Do not continue driving.
Contact a qualified specialist workshop. The red indicator light flashes and the yellow warning light is on. The electric parking brake is defective.
Switch the ignition off and back on.
Release the electric parking brake manually.
Switch the ignition off and back on.
Apply the electric parking brake manually.
If the red control lamp continues You cannot continue driving.
Protect the vehicle from rolling away. Cars with mechanical box gear: engage first gear. Cars with automatic transmission gear: shift the transmission to position. Turn the front wheels towards the curb. Contact a qualified specialist workshop. The yellow warning light is on. The red indicator light flashes for about ten seconds after the electric parking brake is applied or released. After that, the lamp goes out or continues to burn. The electric parking brake is defective.
Switch the ignition off and back on.
Apply the electric parking brake.
If the electric parking brake Cars with manual transmission: engage first gear.
Cars with automatic transmission: shift the transmission to position. Contact a qualified specialist workshop.If the electric parking brake is applied Contact a qualified specialist workshop.
The yellow warning light is on. When the electric parking brake is applied or released manually, the red indicator lamp flashes. The electric parking brake is defective. The electric parking brake is not manually applied.
Cars with manual transmission: turn off the ignition.
