Analysis of cornering lighting adaptive steering headlights & side auxiliary lights

Drivers who have actual driving experience will have a more personal experience of the importance of nighttime cornering lighting. When we drive on a large-curve overpass or on a highway ramp, or drive alone on a mountain road without street lighting at night, the large blind spot on the inside of the curve undoubtedly poses a huge safety hazard. Major automobile manufacturers have provided different solutions, including advanced night vision systems for luxury cars and cornering lighting systems used by most manufacturers. Today we will focus on the two mainstream cornering lighting solutions: headlight follow-up steering and side auxiliary lighting, to see which one is more clever and which one is more practical.

AFS headlight system: The ordinary headlights installed on cars usually have a fixed illumination range. When the car turns on a curve at night, due to the inability to adjust the lighting angle, a "blind spot" often appears on the inside of the curve, which greatly threatens the driver's safe driving at night. The general headlight steering system includes the AFS headlight intelligent follow-up system and the ALS light axis automatic adjustment system. When turning at night, AFS can automatically adjust the illumination center of the low beam according to the vehicle speed and the steering angle of the steering wheel, and automatically point it to the corner to ensure high visibility in the corner. When the rear load is heavy and the body angle rises, ALS automatically adjusts the light axis inclination to avoid interference with the drivers of oncoming vehicles caused by the rising light axis.

Side auxiliary lighting: The purpose of developing side auxiliary lighting is also to illuminate the blind spots of curves at night. The biggest difference from the dynamic steering headlights AFS is the way it works. AFS is achieved by rotating (moving) the reflector cup and bulb as a whole, which means that a motion mechanism needs to be added to the original high and low beam groups. The side auxiliary lighting system cleverly sets a small bulb at a special angle in the headlight. Only when the steering wheel is turned to a certain angle range will the small bulb light up. When the small bulb lights up, it can provide lighting for the blind spots of curves. In principle, the side auxiliary lighting is a bit tricky, but what about the actual effect? ​​Let's see the analysis below.

"The high-end Triumph is equipped with turn headlights"

The AFS headlight follow-up steering system requires a set of motion mechanisms to be arranged in the light group to drive the bulb and the lamp cup to rotate (the specific transmission method varies slightly from manufacturer to manufacturer, but the principle is the same). The timing and amplitude of the movement are all controlled by the on-board computer. The on-board computer will collect information such as vehicle speed and steering wheel angle, and then send instructions to the transmission mechanism to adjust the headlight beam in real time according to the specific driving conditions. The realization of the AFS function requires a complete set of system matching and necessary motion mechanisms, so the impact on vehicle cost is quite obvious.

In terms of actual lighting effects, the headlight beam turns to the inside of the curve very promptly as the steering wheel turns, and can illuminate the blind spot inside the curve before the vehicle reaches the center of the curve. At the same time, the effective light left on the road ahead of the curve is more than that of ordinary headlights. In short, the driver can clearly see the road conditions farther away. If there are pedestrians or obstacles in the curve, the AFS function will detect these conditions earlier than ordinary vehicles.

After actual experience, we found that the lateral displacement of the front end of the headlight beam is about one to two meters, while the actual angle of the bulb is very small, about 3° to 5°. This shows that driving the bulb to turn requires a very precise transmission mechanism, which also leaves us with questions about system reliability and maintenance costs. You must know that the probability of headlights being scrapped in the event of a head-on collision is extremely high.

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When AFS active steering headlights were used by more and more manufacturers, smart engineers suddenly thought, why must such a complex mechanism be used to turn the headlights? Wouldn't it be enough to add a bulb in the headlight to illuminate the inside of the curve? With this idea, the curve side auxiliary lighting system came into being. The biggest difference from AFS is that it saves a lot of actuating parts and has lower maintenance costs. So will the actual effect be better?

The side auxiliary lighting system does not need to affect the original high and low beam structure at all. Engineers only need to match the angle and lighting time of the auxiliary bulbs. In other words, it will not change the original headlight illumination range, but will also illuminate the blind spot inside the curve on the original basis. Therefore, relatively speaking, the side auxiliary lighting system has a wider lighting range than AFS. When I was experiencing a sports MPV for a long time earlier, I experienced the "power" of the side auxiliary lighting system for the first time. It can be seen that the engineers have spent a lot of thought on the tuning. The auxiliary lights are lit at the moment when the author's sight turns to the inside of the curve, and the actual lighting effect is very impressive, and the brightness and range can meet a variety of different driving conditions.

Even if the vehicle is not in motion, the auxiliary bulbs will still light up as long as the steering wheel is turned. This is very convenient for driving at night in places without street lights, especially when you need to turn around on the spot.

"Ford Maxus equipped with steering assist headlights"

So is the auxiliary light bulb controlled by the on-board computer or is there a switch inside the steering wheel? According to the author's observation, when the car is in D gear and R gear, the side auxiliary light bulbs that light up are different when the steering wheel is turned in the same direction, which means that the lighting of the left and right auxiliary light bulbs is not necessarily related to the direction of the steering wheel. From this, it can be inferred that the on-board computer still controls the auxiliary light.

Conclusion: After reading this article, some car owners may wonder, since the technology of side lighting is so mature, why not simply adjust the angle of the light cup reflection, or install a few more side lighting bulbs that are always on, so that the horizontal lighting range of the headlights is greatly increased, wouldn't this completely solve the problem of blind spots on curves? In fact, it is not the case, because when driving on the road, we need to consider not only ourselves, but also other road users. Increasing the lighting range will inevitably affect the vehicles in front, and the reason is the same as blindly using high beams. Why should we build our own happiness on the pain of others?