1 active safety technology
Active safety system refers to a safety system that prevents traffic accidents by taking preventive measures in advance. It is expected to reduce casualties in traffic accidents in the most thorough way. This technology is one of the cutting-edge technologies for the safety of the next generation cars.
1. 1 eye car technology
Volvo's EyeCar concept car can make every driver's eyes at the same relative height, ensuring the unobstructed view of the road and surrounding lanes and the best visibility. This technology can also provide a specific driving environment.
The new technologies adopted in the EyeCar concept car include:
A) The eye position sensor can determine the position of the driver's eyes, and then determine and adjust the position of the seat accordingly;
B) The motor automatically lifts the seat to the optimal height to provide the driver with the best view of the road conditions;
C) The motor automatically adjusts the height of the steering wheel, pedals, center console and even the floor to provide the most comfortable driving position;
D) Some innovative designs, such as rearranged B-pillar, can reduce the "blind zone" in the driver's field of vision;
E) Structural improvement helps to pull the collision force away from the occupants, thus improving the collision safety level.
EyeCar automatically adjusts the eyes of drivers of different sizes to the same height by using electric seats, which solves the problem of vision. At the same time, you can adjust the steering wheel, brake and accelerator pedal, floor and center console to form your own adaptive driving environment. At the same time, the B-pillar has been redesigned and removed from the driver's sight. Because more than 90% of the most critical information received by car drivers is generally obtained from outside the car through eye observation. Therefore, this improvement is of great significance to the safety of automobiles.
1. 1. 1 eye position sensor
Volvo EyeCar uses two different technologies to determine the driver's eye position. The first depends on the unique reflectivity of human eyes, and the second uses the water content of human body.
The main control system of EyeCar includes eye recognition technology. Wherein, the camera located in the upper decorative panel of the windshield scans the driver's seat area to find a pattern representing the driver's face, then scans the driver's face to determine the position of his eyes, and then finds the center of each eye. It takes less than 1s to complete these three steps.
The camera's eye sensor and computer compare the positions of these reflections with the programmed template, and lift the seat until the driver is at the optimal height. Then adjust the brake pedal and accelerator pedal, steering column, center console and floor to match the height of the driver's seat to form a driving environment suitable for personalized requirements.
The system also allows the driver to fine-tune the position of the pedal and steering wheel to obtain the best comfort and is completely ergonomic.
The second technique is to install a capacitive sensor on the ceiling to measure the electric field above the seat. When a person sits in the driver's seat, the water content of the human body will change the surrounding electric field. The sensor detects the distance to the driver's head by measuring this change. Because the distance between the eyes and the head of different people is very small, the best observation position can be obtained by adjusting the seat position so that the head is 7.62cm away from the ceiling.
The design of other facilities of EyeCar also considers the interaction with these new technologies. It moves the control device previously arranged on the dashboard to the console, and controls it through the steering wheel buttons or voice commands designed according to ergonomics. This means that drivers with shorter arms no longer need to stretch their arms to operate air conditioning or audio control. The seat belt is installed in the backrest of the seat, so it can provide the best protection and comfort at various seat heights.
1. 1.2 Other designs to improve safety.
EyeCar eye position fixing system can provide drivers of all shapes with the best forward vision and dashboard perfect angle. The innovative design of B-pillar eliminates the obstacle of lateral vision. At the same time, it also improves the protection against rollover and side impact. Because of the fixed position of the seat, its structure can be used as an unloading channel for side impact force, which can guide the impact force into the roof structure and avoid the occupants.
The design of other components of EyeCar considers the safety during collision. The adjustable pedal has been redesigned to reduce the injury caused by pedal binding or ankle falling off the pedal in a frontal collision. The steering column can also expand and contract in the horizontal direction, which increases the driver's deceleration space.
1.2 CamCar technology
CamCar technology is adopted in Lincoln navigator car, which is helpful to improve the driver's perception ability. Multiple pencil-sized cameras and three switchable video display screens provide drivers with front and rear sight lines, which not only facilitates the operation when parking, but also improves the driving safety in crowded traffic.
Technical features of CamCar include:
A) Forward-looking camera systems installed on both sides of the car enable drivers to bypass large vehicles and see cars or pedestrians in hidden places in advance. In a typical driving scene, when turning left in heavy traffic, the driver can see the opposite vehicle more easily.
B) The lateral rear-view camera provides a wider side view. The coverage of cameras is wider than that of traditional rearview mirrors, especially for adjacent lanes.
C) Four miniature camera installed in the rear of the car and arranged in a fan shape can obtain a panoramic view of the rear of the car. The image is electronically synthesized, with zoom and 160 wide-angle capability.
D) The "Night Eye" camera can work in low illumination when the car is reversing, and it can provide a small image at a close distance behind the car even in the near darkness.
1.2. 1 car display
CamCar's dashboard is equipped with three video displays, a central display and two side additional displays. The displayed image can be changed according to the specific situation, thus providing the most important information for the driver. The real environment of the car poses special problems for the display screen. Traditional TV monitors are too dazzling. Some flat panel displays can't meet the requirements in cold weather and are too sensitive to the viewing angle. In order to solve these problems, Ford researchers introduced a new display mode. This kind of glare-free thin display screen has the advantages of fast response speed, no imaginary edge, viewing from all angles, and extremely wide allowable temperature change range.
1.2.2 Forward camera system
Most people think that the "blind spot" in general driving is the area in the lane directly behind the driver's left shoulder. But if the driver drives behind a big truck or van, the blind spot that the driver can't take care of is much bigger. This line of sight is blocked, which may be a serious safety hazard. For example, the driver may not see pedestrians coming down from the roadside or cars crowded in from both sides. Turning left in this case may be a painful experience.
CamCar camera system uses two pencil-sized forward cameras installed on both sides of the car to provide a view around obstacles. The coverage angle can reach 22, which is equivalent to 300m distance 1 16m wide field of view.
The two extra display screens on the dashboard usually show the backward view of the side, but if the driver wants to bypass the obstacle and know the situation ahead, he can press a button to switch the display to the pictures taken by the two front cameras, so that the driver can see the things ahead around the curve.
1.2.3 enhanced side view
The second part of the CamCar camera system consists of two backward cameras, which continuously provide backward vision of adjacent lanes. Its coverage is much wider than the traditional rearview mirror. So the driver can monitor the incoming car before changing lanes. This kind of rear view has almost no blind spots.
The rear camera, like the front camera, is as big as a pencil and installed on the side of the car, similar to the side mirror. The image is displayed on two additional display screens in the center display screen of the instrument panel. Its lens can provide a wider field of vision without distorting the sense of distance too much. The coverage angle of cameras on each side is 49.
1.2.4 Panorama behind the vehicle
CamCar's rear view function is enhanced by the precise design of four miniature cameras installed at the back of the car. The four cameras are fanned out to capture the road conditions in the vast area behind the car with four independent images.
These images are sent to a complex computer program for comparison and superposition, and then a seamless panorama is synthesized. The total coverage angle can reach 160, which is much wider than the general rearview mirror.
In a particularly long car, the traditional rearview mirror may have a "tunnel illusion" because it is too far away from the rear window glass. Similarly, the dark privacy glass used in the back of modern cars also affects the image of rearview mirrors. Panoramic camera successfully solves all these problems, but it also damages the inherent advantages of privacy glass, which is beneficial to heat dissipation and confidentiality.
1.2.5 night vision camera
When the driver of CamCar opens the reversing field of vision, the central display screen switches to the NightEye low light camera display. This kind of camera can provide detailed images of the area near the rear of the car in daytime or extremely dark light, so as to operate the car safely. This night-eye video image is much more detailed than what the driver sees through the back window. It enables the driver to estimate the distance to the object near the rear bumper. Unlike the parking assistance system that senses distance, this camera can display obstacles.
All these technologies can be combined with other technologies to provide drivers with a bird's eye view of the car and its surrounding scenery. In addition, researchers are also exploring innovative night-eye low illumination technology applied to all cameras to completely eliminate glare caused by headlights and other bright light sources. Therefore, high-tech cameras may form the basis of an integrated anti-collision system.
1.3 sensor car technology
In traffic accidents, pedestrians who collided accounted for a large proportion. The collision warning system technology used in Mazda SensorCar concept car is mainly to reduce the accidents of chasing and injuring pedestrians, which is of great significance to the progress of accident prevention in the future.
The new technologies adopted in the SensorCar concept car include:
A) The laser radar device installed on the scaffolding monitors the movement of people in front of the vehicle, and if it detects that someone walks into the center line of the vehicle, it will light up the warning light on the instrument panel, making the front speaker sound or even honk;
B) The sensor installed in the rear bumper for monitoring the rear traffic situation is controlled by a computer program to determine whether there is a possibility of collision;
C) When the rear-end collision is about to happen, the rear-end collision warning system starts the electric seat belt pretensioner to automatically tighten the seat belt, so as to minimize the danger of injury to the occupant wearing the seat belt. The system will also light the warning icon on the dashboard and give an alarm through the rear speaker.
1.3. 1 pedestrian safety
Pedestrian accidents account for a large proportion of traffic accidents. For example, in India, pedestrian deaths account for more than 40% of traffic deaths, and the other 40% are the deaths of other non-automobile drivers (such as bicycles or Qingqi). In Japan, pedestrian deaths account for 28% of traffic accident deaths, while cyclists and motorcycle riders account for another 365,438+0%. Accident analysis shows that one of the main reasons for the collision between people and vehicles is that the driver did not see the pedestrians in the driving direction, or did not have time to brake when he saw the pedestrians.
The design idea adopted by SensorCar is to provide early warning for drivers, so as to avoid collision. Mazda's SensOECar uses active sensors to monitor the pedestrian traffic in front of the car. When it detects someone entering the driving route of the car, it will issue a warning to remind the driver to take necessary measures.
SensorCar uses lidar equipment installed on the grid to scan pedestrians in front of the car. It sends out a beam of light, which hits the pedestrian and reflects back to the sensor, and then analyzes the reflected wave.
The system can detect pedestrians wearing black clothes 45 meters away from the car, and pedestrians wearing white clothes have higher reflectivity, and the detection distance can reach 60 meters. It can also distinguish people from similar inanimate static objects, such as trees or telephone poles.
If the system confirms that pedestrians will enter the 2-meter-wide car passage and there is a possibility of an accident, it will ring the alarm buzzer in the car and turn on the warning light on the dashboard.
SensorCar will also honk if the speed of the car and the distance between pedestrians indicate the need for emergency braking to avoid collision.
1.3.2 Anti-collision
On the rear bumper of SensorCar, two sensors are installed every 60mm to continuously monitor the surrounding traffic conditions. Like the pedestrian sensor, this sensor also sends its data to a special computer for analysis. The computer compares the distance, approach angle and speed of other cars to determine whether there is a possibility of colliding with them.
If the system confirms that a serious collision may occur, it can sound an alarm through the rear speaker and light a warning icon to remind the driver of the danger.
If the speed of approaching the car is large enough to require emergency braking, SensorCar will judge that a collision is imminent. At this time, the electric retractor will immediately tighten the waist and shoulder safety belts of the front seat, so that the driver and the front passenger can cling to the backrest and headrest of the seat and reduce the backward movement distance when being rear-ended. The accident research shows that when the distance between the occupant's head and the headrest is within 10mm, the possibility of neck injury will be greatly reduced. Because the pretensioner is electric, it can be automatically reset for reuse.
In addition, SensorCar is equipped with an automatic headrest adjustment system, which uses the weight of the occupant to adjust the headrest to the optimal position.
The pedestrian alarm gives a warning sound through the rear speaker of the car, indicating the dangerous direction to the driver.
As long as the engine is running, the system can work whether the car is stationary or running. When the traffic is busy, cars often meet end to end, so it is very important to eliminate false alarms. For example, there will be no rear-end collision if a car catches up from the next lane. Although the system will closely monitor this situation, the safety response will not be initiated unless it is considered that the accident is inevitable. If the vehicle behind follows, be prepared for sudden acceleration and squeeze in at the first time. In this case, an accident may occur. At this time, the SensorCar safety system will start a collision alarm and turn on the shoulder strap tensioning motor.
2 passive security technology
According to the estimation of the Highway Traffic Safety Administration, airbags have saved tens of thousands of lives in the United States since their application in the 1980s.
Ford Motor Company further expanded the concept of passive safety.
A) The hood airbag being studied is a way to protect pedestrians in the initial collision. This kind of airbag can provide leg and hip protection for adults of medium height and above, and chest and head protection for short adults and children.
B) The front airbag can provide secondary protection at the bottom of the windshield, which is helpful to reduce the risk of head injury caused by pedestrians being thrown on the inner wall of the car in the initial collision;
C) The researchers found that although aluminum and steel have different properties, they can achieve the same crashworthiness as steel by adopting appropriate design and technology, including deformation degree and parameter absorption. After reducing the weight, large vehicles will have better compatibility when they collide with smaller cars.
2. 1 external airbag
Ford Motor Company's pedestrian safety car adopts two novel airbags, which can protect pedestrians in collision. One of the two airbags is a hood airbag; One is the front airbag. The combination of the two can reduce the most common pedestrian casualties.
The hood airbag begins to deploy above and beside the bumper. Before the collision, it was excited by the collision warning sensor, and it was inflated within 50-75 ms The inflated airbag was about 137 1mm wide, 558mm high and 127mm thick. Deployed between the headlamps, extending upward from the upper surface of the bumper to above the hood surface. The folding mode and section design of the airbag ensure that the airbag can conform to the contour of the front end of the car when deployed.
If there is no airbag cover, the grille shed and the lower area of the hood may cause chest and head injuries to adults and children of medium height or above.
The time for the hood airbag to remain inflated can reach several seconds, while the time for the inside airbag to remain inflated does not exceed100 ms. ..
Hood airbags can also provide protection for passengers in special vehicle-to-vehicle collisions. When the side of the car is hit by another component, the head of the occupant in the car may be scratched by the hood of the car. At this point, the hood airbag can provide a buffer for this dangerous part.
The function of the front airbag system is to provide secondary collision protection and prevent the occupants from being hit by the bottom of the windshield after being thrown on the hood. The system includes two airbags, each extending from the center line of the car to the A-pillar on one side. Each front airbag is about 686mm wide, 305mm high and 127mm thick. After the sensor detects the initial collision between the pedestrian and the bumper, the airbag is triggered.
It takes about 100ms for the airbag to inflate during the time when the pedestrian flips the hood and rolls to the windshield. After inflation, the two airbags will completely cover the entire width between the left and right A-pillars along the lower part of the windshield, covering not only the bottom of the windshield, but also fatal "hard spots" such as the wiper swing shaft and hood bracket. However, the airbag will not completely block the driver's line of sight.
Because the collision sensor used in the front airbag is relatively simple, it is expected to be put into production earlier than the hood airbag. The collision warning detection of the hood airbag is quite complicated, and extensive research is being carried out to determine the best way to start the two airbag systems.
2.2 Using aluminum, the lighter weight provides the same structural strength as steel.
The development team of Ford P2000 lightweight aluminum prototype specially made several more chassis for crash test to verify whether the safety can meet the expectations.
Ford engineers have proved through long-term tests that aluminum can meet the federal crash test standards like steel as long as proper design and manufacturing processes are adopted.
The engineering analysis of the new P2000 aluminum alloy automobile shows that it can achieve its safety goal. The early 1994 aluminum alloy car has been tested and proved to meet all safety requirements. In the frontal crash test, according to the requirements of the government test, the car collided with the static rigid guardrail at a speed of 56 km/h. The results show that the crashworthiness of the 1994 aluminum alloy car is not less than that of the traditional steel car, and even better than that of the traditional steel car in some places, completely exceeding the standard requirements of the US Highway Traffic Safety Administration.
manufacture
There are many important problems to be solved in the mass production of aluminum cars. Aluminum has a high mass-strength ratio, but its ductility is worse than that of steel, so it is impossible to use spot welding or other traditional assembly techniques that are convenient for connection.
There are many kinds of aluminum alloys. Automotive designers can choose the best materials for specific applications. Ford Motor Company's aluminum cars use various aluminum alloys to provide the required crashworthiness, sag resistance and machinability.
Further improvement is needed to develop assembly technology suitable for mass production of aluminum cars. In fact, so far, all automobile manufacturers are only producing aluminum cars in small batches, and some aluminum cars adopt spatial frame structure, which is not suitable for mass production. Therefore, the future research on aluminum alloy vehicles will focus on how to improve the manufacturing and assembly technology. Through long-term tests on some selected products (such as aluminum engine hood), Ford Motor Company confirmed that aluminum may become a safe material for manufacturing automobile bodies, frames and structural parts.
2.3 Jaguar Art
Jaguar's new adaptive restraint technology system (ARTS) uses a series of sensors to monitor the driver's seat position, the use of seat belts, the mass and position of front passengers, the collision intensity and the direction of collision force when a collision occurs, and then adjusts the deployment of each front passenger's airbag according to the specific collision characteristics. The system can further reduce the injuries caused by improper airbag deployment, especially for smaller front passengers.
Its main technologies include:
A) The electronic sensor in the seat slide rail is responsible for measuring the front and rear position of the driver's seat; Sensors in the seat belt buckles of drivers and front passengers are responsible for monitoring whether passengers wear seat belts; Collision sensors located on the front cross member and the side of the car measure the intensity of the collision. For the passenger seat, there is also a mass sensor to monitor whether there is anyone in the seat;
B) Each sensor transmits information to the central processor of the system, and the central processor controls the pre-tightening action of the seat belt and the deployment of the two-stage front airbag. Can react in 10ms;
C) According to the collision intensity and occupant data, the front airbag can be deployed with high energy or low energy;
D) When the passenger seat is unoccupied, the passenger airbag will not be deployed to save maintenance costs;
E) The driver's airbag is folded in a star-shaped folding way and deployed radially, further reducing the driver's injury when approaching the steering wheel;
F) Ultrasonic sensors are used to detect the accurate seat position of front passengers. If the front passenger is not in the normal seating position, the corresponding airbags will be prohibited from deploying, thus reducing the injuries caused by airbags.
2.4 Child safety
There are fixing points on the back shelf, ceiling or floor of the car to fix the upper straps or straps to limit the movement of the child seat.
The advanced connection system can be used for standard children's seats, so the seat frame can be quickly and reliably connected to the metal rod in the automobile structure. The system can provide extremely reliable and convenient rigid fixing points.
The seat in the rear child safety seat system is very convenient to install and remove. The safety seat frame becomes a part of the automobile structure, which ensures that there will be no mistakes in the connection of the child seat.
For children who are too old to use the baby seat but can't comfortably use the adult waist-shoulder seat belt, they can use the raised seat, which makes the seat belt more suitable.
2.5 rollover prevention safety system
The anti-rollover safety system uses advanced side airbags and sensors to prevent passengers from being thrown out in rollover accidents. These side airbags will deploy from the ceiling and cover most of the side windows. When the sensors monitoring the roll rate and acceleration of the car confirm that it will overturn soon, the airbag will be triggered. The new airbag technology can keep the airbag inflated for 6 seconds, thus providing continuous protection during the long rollover process, and the airbag can provide cover protection for the occupants in the first two rows of seats.
2.6 AdvanceTrac system
AdvanceTrac system can improve the stability of vehicles in bad driving conditions or when drivers misjudge road conditions. The system monitors the driver's operation (such as steering, throttle and braking) and the corresponding vehicle response (roll, lateral acceleration wheel speed). When something out of control is detected, it will brake one or more wheels as needed to restore control.
3 Other safety technologies
3. 1 rescue vehicle technology
According to statistics, after the accident, it usually takes more than 5 minutes for the relevant departments to receive the accident report. Research shows that sending reports to relevant departments through the collision automatic notification system within 1 minute after the collision can save as many as 3000 lives every year.
Ford Motor Company's RescueCar technology can report to the relevant departments immediately after the collision accident and forward the important information of the wounded on the way to the scene.
Its main technologies include:
A)RescueCar system can automatically call the accident rescue and adjustment center after a serious collision accident, and report the exact position of the car based on global positioning satellite (GPS) data;
B) Before arriving at the scene of the accident, the rescuers obtained information such as the number of car occupants, the seating position, the use of seat belts and the deployment of airbags, so as to make corresponding preparations;
C) Vehicle attitude (overturning or rollover) data are also submitted to rescuers to prepare for rescue work;
D) The data about the collision force and the photos of the scene in the car can make medical rescuers prepare for the possible types of injuries;
E) Because the hospital got the accident report and mastered the number of the wounded, it could prepare the appropriate emergency room in advance, and it also bought time for starting the appropriate treatment as soon as possible, thus saving lives.
If the accident analysis and communication device of RescueCar can reach the same popularity as airbags, it can greatly improve the speed and quality of rescuing the injured and save tens of thousands of lives every year. At the same time, the collision data it automatically provides can also help designers design safer cars under realistic conditions.
3. 1. 1 data record
When RescueCar detects a collision, a series of data recorders begin to collect important information about the location and extent of the collision. Then send the key information to the emergency rescue center through the mobile phone network.
RescueCar is modified from Ford Taurus car and equipped with Ford Motor Company's personal safety system. It contains a sensor that can measure the energy and direction of collision, such as frontal, back or side collision, which are important factors to determine the injury situation. It can record the direction of force to get an accurate description of the accident.
The injury of passengers is closely related to the magnitude and direction of collision force. Even experts who repair damaged cars often find it difficult to determine the direction of collision if they only rely on the structural damage of the car. But this sensor system can provide this key information to the rescue center in time.
RescueCar is equipped with miniature camera, which is responsible for shooting the scene of the accident in the car and sending it to the rescue center. This black-and-white photo can fill the information gap and provide rescuers with accurate data on the number of passengers in the car, the use of seat belts and their exact location in the car. When rescuers have to stop a car to save the injured, it is of great significance to know the exact location of the injured.
A set of sensors, including a Global Positioning Satellite (GPS) receiver, can help guide rescuers to the scene of the accident. RescueCar can broadcast the exact location, driving direction and even posture after the accident, so that rescuers can make corresponding preparations before arriving at the scene.
3. 1.2 calling for help
RescueCar can automatically send all the data related to the collision to the accident rescue center and the local trauma medical center, and establish a language connection between rescuers and the wounded, so that rescuers can respond quickly and have time to prepare before arriving at the scene. It is also helpful for hospital ambulance personnel to diagnose and deal with the typical injuries of specific accidents more quickly.
The automatic call-for-help function is superior to the existing remote communication system, which can ensure that the wounded don't have to wait until someone finds the accident before they can get help. This is particularly useful in rural areas or at night, where nearly half of traffic accident deaths occur. The existing system will only be activated when the airbag is deployed, while the RescueCar system can be activated in a serious accident.
RescueCar system can send collision data through the owner's ordinary mobile phone. Hospitals and rescue centers will receive information from ordinary telephone lines through modems, and then display accident-related information on PC. RescueCar can also be set according to personal preferences, and car owners can disable functions they don't like. For example, if you have concerns about privacy, you can turn off the camera in the car.