Presumably everyone who drives has encountered such a scene, the vehicle in the process of driving on the road, will encounter the need to change lanes, turn, drive in or out of the parking space demand, due to the existence of blind spots in the vehicle itself, only through the two sides of the rearview mirror, it is difficult to accurately view the rear road conditions, if there are vehicles or pedestrians in the blind zone, it will lead to scratching accidents, many traffic accidents are because of the existence of the blind spot of the vehicle, the driver obtained the wrong road information caused.
The so-called blind zone, that is, the driver in the driver's seat can not see the road position through the rearview mirror, the blind spot can not be eliminated directly by adjusting the rearview mirror, in heavy rainy weather, foggy weather, night light dim scene, but also increases the driver's judgment difficulty, resulting in the driver is difficult to accurately judge the position of the rear vehicle through the rearview mirror, at this time if the lane change, turn and other operations, will face greater danger.
Gray areas are blind spots
In order to improve the driver's driving safety, compensate the driver in the driving process can not eliminate the blind spot, blind spot monitoring system (BMS or BLIS) came into being, blind spot monitoring system is also known as parallel assist system, is an advanced auxiliary driving function on the vehicle, the main function is to sweep away the blind spot of the rearview mirror, through the microwave radar detection of the rearview mirror blind zone on both sides of the vehicle in the overtaking vehicle, when there are other vehicles in the blind area, the blind spot monitoring system will pass through the sound, Lights and other strong reminders to remind the driver, so the blind spot monitoring system can effectively ensure the safety of the vehicle during lane change or turning, to avoid the occurrence of scratching accidents.
The emergence of the blind spot monitoring system can be traced back to 1995 by the American engineer George Pratze to the American Association of Engineers proposed the "blind spot rearview mirror", by adjusting the middle and double rearview mirrors to reduce the driver's visual blind spot, mainly in the two sides of the rearview mirror can be installed can see the blind spot situation of the auxiliary curved mirror, to increase the driver's visibility, improve the driver's driving safety, this program has been adopted by many car manufacturers, and has been practically applied.
The widely recognized and accepted blind spot monitoring system is the advanced driving assistance system installed on the second-generation Regal S80 vehicle in 2007, which mainly acquires the image of the side and rear of the vehicle by adding a camera under the rearview mirror, and then uses the image to identify the vehicle or pedestrian behind, thereby reminding the driver of driving safety. However, this system can only be turned on when the speed of the vehicle exceeds 22.5 km/h, and in the case of poor vision such as dense fog and rain, the system will also cause misjudgment.
Blind spot monitoring system is mainly composed of a perception unit, an electronic control unit and an execution unit, the perception unit includes a camera, a detection radar, an ultrasonic sensor, and an acousto-optical alarm. The sensing unit is mainly used to monitor whether there is a vehicle or pedestrian in the blind zone behind the vehicle side, and transmits the sensing information to the electronic control unit; the electronic control unit processes and judges the information obtained by the sensing unit, and outputs the processed signal to the execution unit; the main role of the execution unit is to execute the instructions of the electronic control unit, if there is a vehicle or pedestrian in the blind zone, the sound and light alarm will prompt the driver through the way of image or sound, so that the driver can get better driving prediction.
Composition of the blind spot monitoring system
The blind spot monitoring system is mainly divided into two types of imagery and radar from the technical point of view, and the two technical routes have their own advantages and disadvantages.
Image: Image, as the name suggests, is to monitor the blind area of the vehicle by installing a camera on the vehicle, the camera is mainly installed on both sides of the rearview mirror and the rear of the car, to monitor whether there is a car behind the vehicle in the form of image, but the use of video technology, in bad weather (heavy rain, fog, etc.) will perform poorly, it is easy to produce misjudgment.
Radar: The radar used in the blind spot monitoring system is mainly a short-wave radar of 24 GHz and 77 GHz, the radar is installed on the side or rear bumper, by sending microwave detection on both sides of the vehicle and the rear of the vehicle, the vehicle driving speed is greater than 10KM/H automatic start, real-time to the left and right 3 meters rear 8 meters range, issued a detection microwave signal, the system of the reflected microwave signal analysis and processing, you can know the distance, speed and direction of motion of the vehicle behind the information, through the system algorithm, Exclude fixed objects and distant objects, when detected in the blind zone there is a vehicle approaching, the indicator light flashes, at this time the driver can not see the vehicle in the blind zone, but can also know through the indicator light that there is a vehicle behind, the lane change has the risk of collision, if the driver still does not notice the flashing of the indicator light at this time, hit the turn signal, ready to change lanes, then the system will issue a "beep beep" voice alarm sound, once again reminding the driver that there is a danger in changing lanes at this time, and it is not advisable to change lanes. Through the entire driving process, uninterrupted detection and reminder, to prevent traffic safety accidents caused by potential dangers such as bad weather, driver negligence, rearview mirror blind spot, and novice hands on the road during the driving process. Compared with the technical method of using imagery, the radar scheme is not affected by the image of the weather, and the microwave does not rely on air transmission, so the detection ability of microwaves and the speed of the vehicle are not correlated.
Blind spot monitoring system is the existing advanced driver assistance system application of a more common technology, with the development of technology, the era of automatic driving will eventually come, after the popularization of automatic driving technology, blind spot monitoring system still has the significance of existence? From the previous article, we can understand that the essence of the blind spot monitoring system is to monitor whether there is a vehicle entering the blind area on both sides of the vehicle and the rear, so as to remind the driver of driving safety through sound or light, mainly a technology that assists the driver to drive. The premise of the realization of autonomous driving is that the driving process of the vehicle does not require the participation of the driver, and at that time, is it necessary for the blind spot monitoring system to exist?
The author believes that after the popularization of automatic driving technology, the task of vehicle driving is handed over to the vehicle itself, the identification of road conditions is still very important, and the diversified monitoring of roads will ensure the safety of vehicles when driving automatically. Blind spot monitoring systems will also change to another form as autonomous driving technology upgrades.
In the L4 level of automatic driving, although the vehicle can achieve the function of autonomous driving, but still need safety officers to assist in identifying road conditions, in the necessary situation, or need safety officers to take over the vehicle, at this time the blind area monitoring system will play its own role as now, when the blind spot of the vehicle appears vehicle or pedestrians, will still be through sound and light to remind the safety officer, so as to ensure the safety of vehicle driving.
When the automatic driving technology reaches the L5 level, the role of the safety officer is no longer needed, at this time the blind spot monitoring system will be transformed into a road monitoring system, constantly monitoring the road conditions, providing a more perfect road condition for the vehicle, sound and light reminders will also disappear, the vehicle will autonomously realize the identification of the two sides of the vehicle and the rear of the vehicle, and collect road condition data to the system, so that the system can do a good job of driving prediction and provide passengers with perfect automatic driving services. The development of advanced driver assistance systems will be gradually progressive, the existing advanced driver assistance system is more to assist the driver to drive safely, with the improvement of automatic driving technology, these advanced driver assistance systems that assist drivers will also be upgraded by technology, transformed into another technical direction in automatic driving technology.