Audi safety assistance driving system

Today's Audi driving assistance systems range from adaptive cruise control with stop & go function to speed limit display. Audi provides rich assistance systems to make driving more convenient and controllable. In some high-end car series, various auxiliary systems are closely connected, which improves the intelligence of the system, and the functions are more comprehensive and powerful.

Adaptive cruise control with stop & go function

The core part of Audi's driver assistance system is adaptive cruise control with stop & go function, which is an automatic distance keeping system. In the speed range of 0 to 250 km / h, the system controls the vehicle speed and the distance to the vehicle in front through automatic acceleration or automatic braking.

The system uses two radar sensors (automatically heated when cold) with a frequency of 76.5 GHz, a radar wave covering a 40-degree field of view and a fan-shaped area of ​​about 250 meters. The sensor control unit processes the signal to monitor the situation in front of the car.

The driver can influence the function of the ACC system. From sports to comfort, the following distance from the car in front and the intervention force of the control system are adjustable in stages. The maximum deceleration of the system is limited to about 4 m / s2, which is almost one third of the maximum deceleration.

Faced with stop-and-go traffic conditions, the ACC system can automatically slow down the driving speed until it stops. After a short stop at traffic lights, the car restarts automatically and keeps up with the car in front. If it is after a long stop, the driver must step on the accelerator or operate the control lever to continue to follow the car. Before starting, the system will check the image data provided by the camera on the rearview mirror in the car. In this way, the system can detect potential dangers-such as pedestrians who want to grab the road at the last minute of the green light. The ultrasonic sensor of the parking system provides more detailed information to monitor the car's starting process.

The ACC system closely interacts with other driver assistance systems. It uses data from up to 27 control units to continuously analyze the surrounding environment of the car and can provide predictive support even in complex situations. For example, the system cooperates with the navigation system to know the selected travel route in advance and calculate the lane on the curve.

The ACC system can come in handy in many situations. Whether it is faster than a right-turning car on a rural road, or encountering other cars entering the lane of the car on the highway, the system ’s sensitive and calm response is comparable to highly skilled drivers, which makes driving more Smooth and coordinated.

Audi provides multiple versions of the ACC system for different vehicle models, including those without stop / start functions. Depending on the degree of networking and the level of expansion, the functions of each version are slightly different.

Audi Active Lane Keeping

Audi's active lane keeping function is one of the auxiliary systems currently being provided by Audi, and most Audi models equipped with electro-mechanical steering assistance can be equipped with this function. When the vehicle speed exceeds 60 km / h, Audi's active lane keeping function uses a camera installed in front of the rearview mirror to detect lane markings. The camera can cover a distance of more than 50 meters in front of the car and a road range of about 40 degrees of field of view, providing 25 high-definition images per second.

The on-board software is responsible for monitoring the lane markings and the lanes in the two lane markings from the image. If the car deviates to a certain lane marking without turning lights, the system will help the car drive back to the "right lane" through a small and effective intervention in the electromechanical steering system. The driver can use MMI to determine the reaction speed of this intervention and whether to combine the steering wheel vibration warning. If the driver chooses early intervention, the system can keep the car driving in the middle of the lane. The active lane keeping feature makes Audi stand out from the competition.

Audi side assist

Audi side assist is a parallel auxiliary system, which can be provided to all Audi models. This function can monitor the traffic situation behind the car and warn the driver before a dangerous lane change.

When the car reaches a certain speed, Audi's lateral assist system will be activated. Two radar sensors with a frequency of 24 GHz located in the rear-view mirror of the car are responsible for monitoring the situation within 70 meters behind the car, and their data are analyzed by the computer.

When it is detected that a car appears in a dangerous area-such as the blind zone of the rearview mirror of the car or is quickly approaching the car from the rear-then the system enters the so-called "prompt" phase. At this time, the yellow LED indicator on the outside mirror bracket will light up slightly, but it will not interfere with driving. The driver of this car can only see this prompt when looking directly at the rearview mirror.

If the driver of the car is turning the turn signal to change lanes at this time, the brightness of the indicator light on the exterior mirror bracket will suddenly increase and flash many times. At this time, the system has entered the "warning" stage, such warning signals will make it difficult for the driver of the car to ignore. Because the LED indicator light is directed to the driver, its brightness can be changed according to the ambient lighting brightness, or it can be set separately through the MMI control terminal.

Night Vision Assist

The core of the night vision assistance system is the far-infrared camera located in front of the car. It covers a 24-degree angle of view and is equipped with a glass cover to protect against stones. In cold weather, the glass cover can be heated and cleaned when dirty. As a far infrared system (FIR), the camera can capture the thermal radiation of objects in the scene. The computer is responsible for converting the data collected by the camera into a black and white image and displaying it on the central display of the dashboard in the car.

The detection range of the far-infrared technology can reach 300 meters, far beyond the range of the car's high-beam headlights, and will not fail due to the influence of headlights or similar light sources. The most important thing is that far infrared can focus on the most important object-people. Regardless of whether the pedestrian is light or dark in the environment, because the human body emits heat, they are always bright and conspicuous in the far-infrared image, while the colder surrounding environment appears darker.

The image processing software can detect pedestrians within a range of about 100 meters. When analyzing data, the analysis software pays special attention to objects that resemble human outlines, as well as bright round objects-that is, human heads. The system highlights the detected pedestrians with yellow markers on the display in the center of the dashboard. If the control unit believes that a danger may occur, for example, a pedestrian is walking on the road closer to the car, the pedestrian in the display will be marked in red and an audible warning will be issued. Warning signs will also appear on the head-up displays of some Audi models.

Whether it is marking, audible warning or image contrast, can be set through the MMI system. Like other auxiliary systems, night vision auxiliary systems also have certain system limitations. For example, if the temperature is higher than 28 degrees Celsius, the function of highlighting pedestrians will be turned off.

Parking assist

Audi provides various parking systems for all models. These systems use either ultrasound, acousto-optic signals, or rear-view cameras that can display images through on-board displays. Among them, parking assistance can be described as a particularly convenient solution. When the driver reverses into place, the parking assist system is responsible for all relevant steering maneuvers. This applies to both vertical parking and parallel side parking. When the car is driving at a slower speed, the system will scan the roadside vacancy and locate the appropriate parking space in a two-dimensional manner through the ultrasonic sensor on the side. After the system finds a suitable parking space, it will notify the driver through the display screen.

If the driver wants to park and put in reverse gear, the parking assist system will automatically activate and complete all relevant steering maneuvers with the assistance of the electromechanical steering assist system. The driver must continue to be responsible for acceleration, shifting and braking. The system also provides support through visual and acoustic signals. When parallel side parking is required, it only needs to be about 0.8 meters longer than the length of the car to complete. If necessary, the parking assist system will perform multiple “forward and backward” movements to complete the parking. When driving away from the parking space, the system can also provide similar support.

Audi's latest achievement in this area is an enhanced parking system equipped with a 360 ° omnidirectional camera. Four small cameras located on the integrated radiator grille, the rear of the car and the side mirror brackets are responsible for recording images of the surrounding environment of the car.

The driver can select images from different angles of view through the on-board monitor to observe the real environment around the car, including the top-view angle. The enhanced parking system with 360 ° omnidirectional camera not only improves safety when parking, but also ensures safety at narrow intersections. The system provides a special perspective to display the real-time situation in front of and behind the car, allowing drivers to see the traffic situation at the intersection before and after.

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